The Animal Nutrition

Page 1

Issue Nยบ 1

August 2020




The Global Media in English for Animal Nutrition & Feed Professionals nutriNews® agriNews®



t is a pleasure for all of us to introduce nutriNews, TheAnimalNutrition magazine, the Englishlanguage magazine for the international market of Animal Nutrition. nutriNews, the most widely read communication tool in the Spanish-speaking animal nutrition sector presents its international sister, nutriNews International! nutriNews International has been created conceived as a reference and dissemination space for specialists in this sector, involving companies, institutions and international researchers. Despite the differences that may exist between the different countries, animal nutrition and the resources and specialties to improve the results of animal productions are the same throughout the world. The need to correctly cover the nutritional requirements of our animals and provide them with safe food requires that our knowledge of how to optimize them is a unique and global priority worldwide.

For this reason, nutriNews International was born with the desire to show the world how animal nutrition develops around the world.



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This initiative will provide an opportunity for all professionals related to this sector to discover what is being done in other places of the world and to reflect on whether some of these practices could be useful to them and could be applied in their diets. We hope that all our readers recognize in nutriNews International a practical tool to achieve their goals, to feed our animals in a healthy and safe way in order to maximize the much needed animal protein sources worldwide.

We hope you like it and keep reading for a long time! Welcome to the nutriNews family! Free distribution magazine AIMED AT FEED PROFESSIONALS

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1 nutriNews International June 2020


Relevant aspects of quality in feed granulation


Mario García Jiménez1 Pedro Medel de la Torre2 1 3F Feed & Food, S.L. 2 Innovabiotics S.L.

Dr. Alfred Blanch Consultant Stressful situations negatively affect the balance of the intestinal microflora and the immune response of the animals. Several strategies for the use of probiotics, prebiotics and synbiotics, are increasingly becoming the subject of research looking at reducing pathogen load in swine production.

Feed pelleting is done for many reasons. It improves productive performance, mainly because it prevents the animals from wasting feed at the troughs and from selecting certain ingredients.


Raw materials: Citrus pulp

Application of probiotics, prebiotics and synbiotics in swine


The importance of feed presentation in broilers

Paloma García Rebollar Polytechnic University of Madrid

FEDNA (Spanish Foundation for the Development of Animal Nutrition)

It is defined as “a product obtained by means of pressing citrus fruits during the elaboration of juices and subsequent drying . In the industrial production of citrus juice, 30-50% of the weight of processed fruits constitute the residues; they include seed, skin, pulp and peel.

To understand the possible benefits of pelleted feed compared to meal presentation, it should be considered that the effects of feed form and particle size on the bird are totally different. Those two factors explain the advantage and inconvenience of each feed presentation.

2 nutriNews International August 2020


Use of algae in animal feeding – Ruminants Fernando Bacha Technical Director, NACOOP Currently, algae are only in marginal use due to its relatively high cost. It is estimated that they may be important protein sources in the future, since the animal nutrition sector needs to find alternative protein sources that can replace the traditional ones such as soybean.


ABSTRACT: Carbon footprint of dairy goats Carlos FernĂĄndez1 Fernando Bacha2, 1 Polytechnic University of Valencia 2 NACOOP S.A., Madrid The present study is a theoretical approximation with values determined in the trial conditions and using the individual goat as a model. The aim of this trial is to reduce the protein content of dairy goat diets in order to decrease the excretion of N in faeces and urine. The responsibility for the articles, reports, press releases and communications falls exclusively on the authors. The editor is only responsible for his articles or editorials. Neither the publisher nor the authors assume any responsibility for the damages that may be generated, whatever their nature, as a consequence of the use of the data and information contained in this magazine.

3 nutriNews International August 2020



Mario García Jiménez1 and Pedro Medel de la Torre2 3F Feed & Food, S.L. 2 Innovabiotics S.L.




eed pelleting is a process that converts a finely ground mixture into denser

granules (pellets), generally of cylindrical shape.

Figura 1. Transformación de la harina en granulo.

4 nutriNews International August 2020 | Relevant aspects of quality in feed granulation

Body weight gain (BWG) (g/bird)

FCR (g/g) 3.5

450 Feed pelleting is done for many reasons.


It improves productive performance (Figure


1), mainly because it prevents the animals


from wasting feed at the troughs and from selecting certain ingredients.

3 2.5




Additionally, pelleting increases feed


density, which results in reduced


transportation costs, improved farm management and better feed hygiene. It is

1.5 1 0






Proportion of fine particles in the feed (%)

also said to improve feed nutritional quality, but this effect has not been so clearly

BWG (g/bird)


FCR (g/g)

Figure 1. Effect of pellet quality on BWG and FCR in fast growing male chickens after 4 days of treatment (starting age: 19 d) (Quentin et al., 2004)


The pellet is formed by compacting and forcing the passage of particles through the holes or channels of the die, using a mechanical process (AFFCO, 2000; Figure 2).

Raw material


Ring die

Ring die




Die channels

Figure 2. Formation of pellets in the die of a pelleting machine.

5 nutriNews International August 2020 | Relevant aspects of quality in feed granulation

FEED FORMULATION. Characteristics of the raw materials

Factors affecting feed pelleting Several factors affect pelleting. Three of them stand out among the others (Behnke, 1994; Figure 3):

The individual properties of each raw material affect the pelleting process. Water absorption capacity is one of the most important factors to be considered.

Feed formulation

It positively influences feed conditioning and, consequently, the quality of the


pellet and the performance of the Particle size

pelleting machine. The water absorption capacity of raw




materials generally depends on the moisture content when entering the mill,


particle size and particular characteristics.


The moisture absorption capacity of a raw material will be lower for



higher initial moisture and larger particle size.

Formulation Conditioning Particle size Compression/diameter Cooling Performance of the machine

*Feed mill


Figure 3. Factors affecting the granulation (Behnke 1994).

6 nutriNews International August 2020 | Relevant aspects of quality in feed granulation

In general, fibers are good at absorbing

Type of starch

water but, unlike starch, they do it very

In the case of cereals, the type of starch and protein affect the water absorption capacity. In general, floury starch (wheat, rye, barley, oats) has a higher water absorption capacity compared with vitreous starch (corn). Also, the more suitable for breadmaking cereal proteins are, the better their water absorption capacity will be. This explains the better pelletisation of breadmaking cereals such as wheat and rye, compared with barley, oats and corn (Table 1).

slowly. The speed depends on the degree of lignification and the heat treatment the ingredient had undergone. The greater the degree of lignification, or the more intense the heat treatment, the slower the water absorption will be. During the pelleting process, there is little time for water absorption in the conditioner. Therefore, rations higher in fibre, or with fibre of lower hygroscopicity, will have a suboptimal conditioning process, rendering pellets of a lower quality.

Type of fiber The fiber content of raw materials also


affects their water absorption capacity

However, fibrous products, as well as dairy products, have an indirect positive effect on the quality of the pellets, since they tend to reduce the performance (kg/h) of the pelletizer (lower Press Capacity Factor, Table 1). As we will see later on, lower throughputs indirectly improve the quality of the feed to be pelletised, as it spends longer time in the

Table 1 reports the Pelleting Quality Factor (PQF) and Press Capacity Factor (PCF) for the main raw materials, according to (Payne et al., 1994).

die compression channel.

7 nutriNews International August 2020 | Relevant aspects of quality in feed granulation

Table 1. Pellet Quality Factor and Press Capacity Factor of different raw materials.

Fat content Another characteristic that affects pelleting is the fat content of the


feed to be pelletized. The fat content of the feed






added in the mixer and in the press




or conditioner.

























Fat negatively affect the conditioning




of the feed. Due to its hydrophobic







depends on the fat content of the raw materials, as well as on the fat

Unlike water absorption capacity, which positively affects granule quality and the performance of the pelletizer, the fat content of the feed generally has a positive effect on performance, but a negative impact on quality.

effect, it impairs the mixing with the moisture of the feed.

However, a better performance of the pelletizer is usually observed in diets containing high fat levels.

This effect is due to the lubricating capacity of the fat, which reduces compression time but impairs quality. This lubricating effect forces the distribution of the fat into four different moments: 1 – raw materials; 2 – addition to the mixer; 3 –spraying on the granulator press; and 4 – (if it is necessary to add more fat) addition to relubrication distributors, in the phase following press.

8 nutriNews International August 2020 | Relevant aspects of quality in feed granulation

Among the raw materials that compose the feed, molasses has a different performance during the


pelleting process. Due to its viscosity and high sugar content, the adhesion of particles is facilitated, which could improve pellet quality. However, this adhesion occurs very quickly and it is enhanced after cooling, which could substantially reduce the moisture absorption capacity of the feed if it reaches the press when it is already cold. Therefore, the effect depends mostly on the time lapse between

Figure 5. Addition of molasses to the molasses mixer.

adding molasses to the mix and the moment in which feed reaches the press. In general, if the molasses is dosed long before it reaches the press, either mixer, it forms small agglomerations with the other raw materials. When


in the molasses mixer (Figure 5), or in the


those aggregates, already cold, reach the conditioner the steam inflow is adversely affected, hindering moisture absorption and impairing conditioning.

Figure 6. Addition of molasses to the conditioner.

If, instead, molasses is hot when added to the conditioner (Figura 6 ), no negative effects on feed conditioning are observed. This allows for adding higher amounts of molasses in the feed, which is relevant for some ruminant diets.

9 nutriNews International August 2020 | Relevant aspects of quality in feed granulation

In the following sections we explore other factors that affect durability, which includes all the aspects influencing feed conditioning and compression. Also, we will deepen our understanding of the influence of raw material particle size, moisture absorption capacity, the relation diameter/matrix compression and the performance of the granulator.

MEAL CONDITIONING Meal conditioning should be considered as the key process of peletization, since everything that favors conditioning directly affects the quality of the pellet and the performance of the peletizer.


Conditioning is the process through which the meal is mixed with the moisture from steam or other ingredients added to the conditioner (Figure 7). The objective is to form a homogeneous mass that will form the pellets after passing through the die.

The higher the meal uniformity and the more embedded the liquids are, the better the pellet quality and the pelletizer performance will be.


Figure 7. Meal conditioning


Conditioned meal

10 nutriNews International August 2020 | Relevant aspects of quality in feed granulation

Figure 8. Effect of conditioning temperature on pellet durability. 100 90 80 70

There are two factors closely linked to feed conditioning: temperature and moisture. 1

70 60 50 40 40 30

This is the result of a higher temperature allowing moisture and other liquids to better penetrate into the meal, rendering a more uniform conditioning.













Temperature ยบC

In a first stage, when the meal is dry, consistency slowly increases when moisture is added.

Figure 8. Effect of humidity on pellet durability.

From a certain moisture level (different for each type of meal), the water takes up the interstitial spaces between meal particles, resulting in capillary attraction (due to the surface tension of water), cohesion between particles, and a rapid increase of consistency up to a maximum.

90 90 88 88 86 86

Durability %

84 84 82 80 78 76

However, that is not true for the moisture (Figure 8).



Durability %

60 50

As a general rule, for the same moisture content in the meal to be pelletized, the quality of the meal improve as temperature increases (Figure 7).

Close to this maximum the meal conditioning is ideal for pelleting.

80 78 76 74

74 72 72





Moisture content of the meal entering the press


Over the maximum, the thickness of the water film between particles is increased, weakening the capillary action. Then, the mass goes from a plastic consistency to a liquid consistency, which makes pelletizing impossible. The feed forms layers between the die and the rollers, clogging the pelletizer.

11 nutriNews International August 2020 | Relevant aspects of quality in feed granulation

The problem we face when pelletizing is that moisture and temperature are connected, since we increase temperature through the steam and it also incorporates moisture.

The “drying� effect of the steam ramp is similar to the Foehn effect that occurs in the mountains. A mass of humid air coming from the sea ascends over the mountainside. As it goes up it becomes cooler, reducing its water holding capacity. Then, the moisture condenses to form clouds and precipitates as rain. Once it reaches the summit, it begins to descend on the other side of the mountain and warms up again, resulting in dry air (Figure 9).

For this reason, one of the key aspects for meal conditioning is to use dry steam. To get dry steam in a feed mill, a steam ramp is used (Figure 9). The steam ramp is a device of the steam circuit that, through a control valve, reduces the original steam pressure that comes from the boiler.


When the steam pressure is low, the amount of suspended water in the steam is lower. The water excess is removed by the separator and returns to the boiler. Therefore, the higher the difference between the pressure of steam produced in the boiler and the pressure of steam added to the conditioner, the lower the moisture incorporated into each cubic meter of steam. This makes possible to reach higher tempearature per point of misture added.

High pressure steam




Figure 9. Steam ramp

12 nutriNews International August 2020 | Relevant aspects of quality in feed granulation

Safety valve

Pressure reducing valve


Low pressure steam


Smaller particles have larger surface area to volume ratio, resulting in higher capacity of moisture absorption and easier steam penetration. Also, the greater the particle size, the lower the stickiness between particles, and the higher the number of breaking points. Therefore, the smaller the particle size, the better the quality of the granule (Table 1).

Table 2. Effect of conditioning temperature and particle size on the percentage of fines (Behnke 2004)

Figure 10. Steam penetration according to the particle size.




The practical problem is that the current trend is towards increasing feed particle size due to its beneficial effect on animal health (Vukmirovic et al., 2017; Mingbin et al., 2015).


Particle size is another factor of particular importance for the pelletization process. It affects the pellets at two levels: meal conditioning and final stickiness of the particles.


Percentage of fines in the pellet 3.2 mm sieve

1.6 mm sieve









0.8 If we want to have a good pellet with a larger particle size, it is necessary to further control the other factors.

13 nutriNews International August 2020 | Relevant aspects of quality in feed granulation

The die compression and its relation to the die channel diameter are another important aspects of pelletization.



Compression concerns the effective depth of the die compression channel (Figure 11), which is where the feed is compressed and transformed into pellets. The higher the compression, the better the pellet quality. However, this reduces the performance of the pelletizer, since the increase in friction makes more difficult for the feed to pass through the die (Figure 12).

Figure 4. Die compression.


We must have a compression and a relation compression/diameter which make it possible to optimize production with good quality of the pellet. When optimising pellet quality, we should not forget that the performance of the pelletizer is inversely associated with the quality. All other factors being equal, a higher performance implies a shorter time in the die channel. This results in a drop in durability (Figure 11).

Figure 11.Effects of compression and pelletizer performance


100on the durability of the pellet (Stark, 2016)







40 40 30


Durability %

Durability %


50 35%

20 20 10



Compression, mm

44 mm




35 mm


40 40

20 20

29 mm






Production, kg/h

14 nutriNews International August 2020 | Relevant aspects of quality in feed granulation


The main factors affecting pellet durability are aspects of feed conditioning and feed compression. Steam quality is essential, since it provides heat and moisture for meal conditioning.


Meal temperature always has a positive impact on pelletization. However, meal moisture, which is affected by moisture from other sources (environment, raw materials, water added to the mixer, moisture provided through steam) has an optimal point. Beyond such threshold, quality and performance show an exponential decline, even clogging the pelletizer.

Other important factors are: Particle size of the raw materials Moisture absorption capacity The relation diameter/compression of the die Performance of the pelletizer

Quality in feed granulation.


15 nutriNews International August 2020 | Relevant aspects of quality in feed granulation

RAW MATERIALS CITRUS PULP Paloma García Rebollar Polytechnic University of Madrid Citrus pulp is a by-product of the industrial

Definition & Classification

extraction of juice. The term “citrus” comprises different fruits from the genus Citrus:

Orange Oranges account for approximately 54% (125

raw materials

million tons) of the annual global citrus production.

Tangerine Tangerine accounts for 27% of the annual global production of citrus.

16 nutriNews International August 2020 | Raw materials: Citrus pulp

Lemon & lime The remaining amount consists of lemons and limes (13%). and grapefruits (FAO. 2017).

The residues of the industrial production of citrus juices represent 30-50% of the weight of the processed fruit. They comprise:

Seed Unsaturated fatty acids.

Skin Source of oil and phenolic compounds.

raw materials

Pulp Pulp and pulp cells, rich in sugars and soluble fiber (pectins)

Peel Rich in molasses, pectins ans essential oils.

It is defined as “a product obtained by means of pressing citrus fruits during the elaboration of juices ( and

Pulp distribution as a fresh product (moisture

subsequent drying (”.

content >78%) is limited to areas close to the processing plants. For this reason

If pectin is removed. this is also indicated

dried citrus pulp is the one commercialized

in the designation. It can also contain up


to 1% of anhydrous methanol, ethanol ad propane-2-ol.

Citrus pulp is listed in the category “Other seeds and fruits, and fruit by-products” of the Catalogue of Feed Materials of EU Regulation 2017/1017, with the numbers (fresh) and (dried). It is also listed in the Crude Fiber Obligatory Declaration (without maximum level).

17 nutriNews International August 2020 | Raw materials: Citrus pulp

Pulp-making process 1. WASHING.

The juice is filtered to separate the floating pulp. The residue is added to

The juice extraction process starts by

the pulp.

washing the fruit to eliminate leaves, dirt, and peel oils that can contain pesticide

The pulp is taken to storage silos for


transportation to farms, where ruminants

2. SEPARATION OF OILS FROM PEELS. The peel’s essential oils (mainly d-limonene, of pronounced bitterness)

consume it directly. Alternatively, it is dried and, after removing pectins, it is used to produce pellets for animal feeding.

are separated by pressing the whole fruit. During drying, calcium hydroxide or


carbonate is included to facilitate the

Then. cuts are made Through the fruit’s

raw materials

peel to allow juice extraction.

release of bound water. Then, the material is pressed to separate the molasses.


The residue is dried in rotating

Skins. membranes. pulp and seeds.

drums and 20-50% of the molasses are incorporated into the pulp. This makes it darker, increases sugar content, and proportionally reduces the content of insoluble fiber. The fresh pulp can be easily ensiled, and no treatment is needed since it is ground. However, it is recommended to ensile it with cereal straw to reduce effluents and sugar losses, as well as to increase silage effective fiber.

Image of Agroplus

18 nutriNews International August 2020 | Raw materials: Citrus pulp






Dry matter

% Dry matter




Crude protein

% DM




Crude fiber

% DM





% DM





% DM





% DM




Crude fat

% DM





% DM





% DM





% DM







g/kg DM





g/kg DM





g/kg DM





g/kg DM





g/kg DM




Nutritional values for ruminants

raw materials

Table 1. Composition and nutritional value of citrus pulp


Metabolizable Energy





Milk forage units (UFL)

kcal/kg DM




Meat forage units (UFV)

kcal/kg DM




Net energy of lactation

kcal/kg DM




Net energy for maintenance

kcal/kg DM




Net energy for growth

kcal/kg DM







Nutritional values for swine Metabolizable energy Net energy for growth

kcal/kg DM




Net energy for sows

kcal/kg DM




1 FEDNA (2018) number of analyzed samples = 95; 2NRC (2016) n = 1189; 3BRASIL (2017) n = 2. ** 0.95%MS in fresh pulp

19 nutriNews International August 2020 | Raw materials: Citrus pulp

Chemical composition The composition is very variable according to: Type of fruit Degree of maturity Growing conditions Juice extraction process Dry matter is characterized by: Sugars (18 to 65%). Soluble fiber (7-42%. mainly pectins). Insoluble fiber (12-43% NDF). Ash (3-20%), according to the amount of calcium carbonate added for drying. Lower in the fresh product.

raw materials

ProteĂ­n (5-11%), low level. Fat (1-8%), it varies depending on the presence of seeds (0-15%) in fruits.

Lemon pulp has a lower content of sugars (28% vs 45% DM), but a higher content of soluble (26 vs 20% DM) and insoluble (31 vs 21% DM) fiber, when compared to orange or tangerine. The latter two do not differ in their chemical composition.

20 nutriNews International August 2020 | Raw materials: Citrus pulp

Nutritional value

Use in animal feeding

Citrus pulp has a high potential for degradation in the rumen (>90%)

Citrus pulp is a product with high energy

and for apparent digestibility in swine

value for ruminants and swine, similar to

(>78%). Due to this, it is often used to

barley grains in terms of metabolizable

replace cereals (barley) in animal diets.



In the rumen, this replacement leads to lower levels of propionic and lactic acids, which helps to prevent acidosis. However, it does not provide an input of


effective fiber to the diet. In monogastric diets, it can increase

It can be added to the diet at high levels (>20% DM), particularly in lactating diets for highly productive animals. The inclusion levels of dried pulp are between 10 and 15%, up to a

digesta viscosity and slow down its

maximum of 20% in sows, without

passage through the digestive tract. This

affecting the productivity.

creates a feeling of satiety and better

It is a very palatable product due to its

intestinal health in sows, as well as in

pleasant aroma and high sugar content,

pigs at the end of the fattening period.

although its incorporation into the

raw materials

diet should be gradual to facilitate the digestive adaptation to increased levels of soluble fiber.

Conclusions Citrus pulp can be used as a source of dietary


Its fast degradation in the rumen should be


energy, replacing cereals in the diet.

In swine, it is recommended to add

considered to avoid reducing milk fat and protein production.

citrus pulp to the diet mainly at the final growth phase (80 to 120 kg) to acidify the intestinal digesta and reduce the counts of pathogenic bacteria (Cerisuelo et al.. 2010). Also, it should be used at the pregnancy phase to decrease abnormal behavior

Raw materials: CITRUS PULP



21 nutriNews International August 2020 | Raw materials: Citrus pulp



Dr. Alfred Blanch Consultant

22 nutriNews International August 2020 | Application of probiotics, prebiotics and synbiotics in swine


n livestock systems, the animals are often subjected to stressful elements (type pf management, diet changes, etc). They can cause an imbalanced intestinal ecosystem, which increases the risk for certain infections. More specifically, in swine production, most stressful situations are related to the weaning and post-weaning periods (maternal separation, end of immunity transfer through the milk, change to a solid diet, transfer to a different facility, and the need for mixing with unfamiliar pen mates). All these factors can negatively change the balance of the intestinal microflora and the immune response of the animals,

leading to an increased susceptibility to intestinal disorders, enteric infections and diarrhea (Modesto et col., 2009). The success of the weaning and post-weaning periods inevitably depends on the addition of metaphylactic antibiotics and other compounds such as ZnO to the diet. However, European authorities are increasingly concerned about the excessive use of this type of medication. As a result, they have generated several strategies to cope with what may become a reality in the near future: a drastic reduction in the inclusion of medicated premixes in animal diets.


Stressful situations negatively affect the balance of the intestinal microflora, as well as the immune response of animals.

23 nutriNews International August 2020 | Application of probiotics, prebiotics and synbiotics in swine



These strategies include the use of probiotics. Such products are increasingly becoming a subject of research looking at reducing pathogen load in swine production. Although the ultimate aim is to control the occurrence of gastrointestinal conditions during the first stages of life, there are also projects researching probiotics in fattening pigs and breeding sows.

The probiotics are being used in all the swine production phases.

Recently, a group of researchers from the University of Copenhagen (Larsen et col., 2014) identified several bacterial strains belonging to the genus Bacillus, isolated from soil, feces and fermented foods. The results indicate that these strains are ideal for using as probiotics in animal nutrition. In fact, some of these Bacillus species were the first ones to be used in swine nutrition, and their efficacy has been proved through studies conducted for many years. Particularly relevant are the extensive studies conducted by Alexopoulos et al. (2004), which showed that the administration of B. licheniformis and B. subtilis spores reduces morbidity and mortality in newly weaned piglets, besides increasing production performance.


Also, in a trial conducted by Wang et al. (2009), fattening pigs were fed diets supplemented with B. licheniformis and B. subtilis. The results showed a significant reduction in ammonia emission and a decrease of slurry pH. Aperce et al. (2010) observed that B. licheniformis and B. subtilis have some immunomodulatory effect in the intestinal epithelium, which could in part explain the post-weaning improvements in diarrhea episodes when both Bacillus species were added to piglet diets.

The presence of lactobacilli in the indigenous microflora of the animals is well known.

24 nutriNews International August 2020 | Application of probiotics, prebiotics and synbiotics in swine

In short, from the studies on the use of diets, it is clear that the addition of both Bacillus species to the diet positively affects the intestinal ecosystem.

On the other hand, it has been demonstrated that the addition of a B. subtilis strain to diets fed to weaned piglets led to a reduction of E. coli K88 counts in feces, within 24 hours after the exposure to the pathogen (Bhandari y col., 2008).

Enterococcus Some species of the genus Enterococcus have also been subject of numerous studies over the past years.

The oral supplementation of piglets with E. faecium, from birth to weaning, reduced the number of cases of diarrhea and improved performance, the latter observed as a higher average daily gain (Zeyner and Boldt, 2006).

Lactobacillus Several studies have been carried out to evaluate Lactobacillus strains, since its presence in the indigenous microbiota of swine is well known.

Qiau et col. (2015) examined the effects of adding L. acidophilus to diets fed to weaned piglets challenged with an intraperitoneal injection of lipopolysaccharide (LPS). The piglets fed diets containing lactobacilli showed a higher average daily gain, compared with the control group. Also, lactobacilli count in rectal samples was significantly higher in the animals supplemented with probiotics, compared with the control group. It was also shown that the addition of L. acidophilus to piglet diets resulted in a significant reduction of E. coli count in the rectum.

Also, Vahjen et al. (2007) observed that the use of E. faecium as a probiotic in weaned piglets reduced colon E. faecalis population, which is responsible for the onset of diarrhea in the post-weaning period (Vahjen et al., 2007).

Of special interest in this study by Qiau et al. (2015) is the lower LPS-induced inflammatory reaction in piglets fed diets containing probiotics, compared with the control animals.

Several studies have found that E. faecium has a beneficial effect when used as a probiotic in diets fed to piglets and sows (Scharek et col., 2005; Lodemann, et col., 2006; Taras et col., 2006; Szabรณ et col., 2009).

Other studies had previously demonstrated the positive effects of lactobacilli species used as probiotics (Takahashi et col., 2007; Nemcova et col., 2007; Collado et col., 2007; Konstantinov et col., 2008; Zhang et al., 2010).


B. licheniformis and B. subtilis in swine

Bacillus licheniformis and B. subtilis have some immunomodulatory effect, which in part explain the improvements in diarrhea episodes during the post-weaning period.

25 nutriNews International August 2020 | Application of probiotics, prebiotics and synbiotics in swine

Yeasts Yeast-based probiotics such as Saccharomyces spp. have also showed positive effects on the productive performance, health status and immune response, particularly in breeding sows and piglets (Shen et col. 2011; Kiarie et

Yeast-based probiotics have also showed positive effects on the productive performance of the animals

col., 2012; Zanello et col., 2013; Trckova et col., 2014; Wang et col., 2015).

PREBIOTICS For many years, the use of different types of prebiotics in swine diets have showed


a beneficial effect of these compounds on the productive performance of

Non-digestible oligosaccharides: TOS, GOS

the animals (Hidaka et al., 1985; Katta et al, 1993; Bouldan et al., 1993). After the first investigations, the studies on the use of prebiotics in swine nutrition have focused on the evaluation of their influence in the intestinal microflora or in the improvement of health status.

TOS (transgalactoligosaccharides)


Smiricky-Tjardes et al. (2003) added TOS (transgalactoligosaccharides) to a diet fed to growing pigs at a level of 35 g/kg. The results showed a significant increase in the fecal populations of bifidobacteria and lactobacilli. Similarly, a combination of galactoligosaccharides (GOS) was fed to the animals at 40g/kg of feed. This resulted in a significantly increased density of bifidobacteria, besides a reduced intestinal pH, compared with the control diet supplemented with inulin (Tzortzis et al., 2005). Also, the same combination of oligosaccharides strongly inhibited the binding of E. coli and Salmonella enterica serotype Typhimurium to HT29 cells in an in vitro assay conducted by the same research group.

The role of prebiotics in swine diets appears to be quite variable. Therefore, further research is needed to clarify such role and their effects on the productive performance and health status of the animals.

Intracellular environment

26 nutriNews International August 2020 | Application of probiotics, prebiotics and synbiotics in swine

In the face of the challenges posed by future regulations regarding the use of medications in animal production, the probiotics, prebiotics or their combination will certainly play an even more important role in swine nutrition and health.


The researchers observed that the inclusion of lactulose improved the average daily gain and increased lactobacilli populations and butyric acid concentrations in the colon. Also, an increase in ileal villus height and a reduction in Pig-MAP (major acute phase protein) serum concentrations were observed.

Application of probiotics, prebiotics and synbiotics in swine

Meanwhile, the addition of probiotics to the diet resulted in a higher L. plantarum count in the ileum and colon, besides an increase in colon lactobacilli population, with a certain tendency to reduce the occurrence of diarrhea. Furthermore, the inclusion of probiotic in the diet promoted a reduction in colonic and ileal ammonia concentrations, and also an increase in ileal villi height and in the number of goblet cells. Finally, the piglets fed diets containing probiotics had a reduction of tumor necrosis factor-alpha. The positive effects of both additives were combined when they were given together to the animals, constituting a complementary synbiotic with certain potential to control post-weaning colibacillosis.


Guerra-Ordaz et al. (2014) investigated the potential use of lactulose (prebiotic), a probiotic strain of Lactobacilus plantarum, and a synbiotic combination of both, to control post-weaning colibacillosis in piglets. The animals were orally challenged with enterotoxigenic E. coli K88, after receiving one of the products for 7 days.


Figure 2. Effect of dietary probiotic, prebiotic, and synbiotic against diarrhea in post-weaning piglets, during 6 days post-oral inoculation with E. coli K88 (adapted from Guerra-Ordaz et al., 2014) Control Prebiotic Probiotic Synbiotic

60 Piglets with diarrhea (%)


P PRE = 0.95 P PRO = 0.09 P Day= 0.007

30 15 0 1






Time post inoculation (days)

27 nutriNews International August 2020 | Application of probiotics, prebiotics and synbiotics in swine


IN BROILERS FEDNA (Fundación Española para el Desarrollo de la Nutrición Animal)

T processing

he use of pelleted feeds improves productive and economic results, and for this reason, this feed presentation predominates globally. Pellet characteristics have become increasingly important in recent years.

28 nutriNews International August 2020 | The importance of feed presentation in broilers

To understand the possible benefits of feeding pellets or meal, it should be considered that the pellet is finely ground while the meal is coarsely ground.

Several studies have demonstrated that broilers from 0 to 21 days of age receiving feed in the form of crumbs or micropellets showed better voluntary feed intake, compared to birds fed diets in the meal form. This resulted in improved growth (+ 15-20%). These advantages tend to diminish with age, particularly when the birds are fed a common pelletized diet. Also, the advantages of pellets are much more important for daily weight gain than for feed conversion, suggesting that the increase in feed intake and the reduction of feed wastage are the main advantages of pelletizing, with little effect on nutrient digestibility.

Prior to the pelletizing, the ingredients are finely ground in order to improve the quality of the final product.


Although they are commonly confused, the effects of feed form and particle size are completely different in poultry, and to a large extent explain the advantages and disadvantages of each presentation type. In this regard, the major advantages of the pellet are observed prior to consumption: from the beginning of the manufacturing process to the moment when the feed is ingested by the bird.

Pelletization changes three key aspects of the feed: Change in the presentation. Loss of moisture, which if not regained will help improve feed conversion. Further reduction of particle size when passing through the pelletizer.

The pelletized form reduces dust formation in the feed mill, losses during transportation, and feed wastage in the feeder.

29 nutriNews International August 2020 | The importance of feed presentation in broilers

Feed wastage is more relevant in old farms, with poor management or badly designed feeders. The pellet form facilitates feed intake by the bird, reducing maintenance needs since the bird eats more quickly and spends more time resting. Also, if the pellet falls to the litter the bird can take it, while this cannot happen in the case of the meal form. Therefore, the granulated form improves feed conversion during this phase.


After ingestion, particle size could be more important than the previous feed presentation with regard to the functionality of the digestive system. Pelletization reduces feed particle size, facilitating the rapid transit of the digesta through the proximal part of the gastrointestinal tract (GIT). As a consequence, the bird is not fully satisfied and tends to increase consumption. On the other hand, due to the higher speed of transit, the pelletized feeds (and, therefore, finely ground) impair gizzard functions due to the reduced development of the muscle layer.


After the bird eats the feed, it goes to the crop, and then to the gizzard, where it loses its structure. So, after ingestion it is difficult to determine if the bird ate mash or pelletized feed. From then on, there is no effect of presentation form, and the main factor is the fine grinding.

On the contrary, the coarse particles remain in the gizzard, improving its function and the development of the organ’s muscle. Also, the higher motility of the wall and mucosa of the digestive tract results in improved health status and productivity. Therefore, in the presence of wet litter and without the use of antibiotics, it is recommended to increase feed particle size even if the quality of the pellet is compromised. The advantages of crumbs or micropellets are largely dependent on the quality of the final product. The benefits are less pronounced or even absent when low quality/excessive fines crumbs, or soft granules that easily break down before getting to the feeder, are used. It is appropriate that the percentage of fines is not higher than 25-35%.

Lilly et al. (2011) observed that for each 10 extra points in the percentage of fines the weight gain of the birds were reduced by 4 g/day from 21 to 38 days of age. Also, carcass and breast weights were reduced by 10 g and 4 g, respectively.

30 nutriNews International August 2020 | The importance of feed presentation in broilers

When assessing the benefits of peletization, a possible increase in mortality should be considered, presumably due to the higher growth speed and lower feed moisture (around 1.0- 1.5%). A moisture reduction can imply that the real improvement in feed conversion (on a DM basis) is lower than estimated. In some cases, the pelleted feed can be excessively dry (for example: during summer, due to the use of durum wheat from warm regions, or pelletization using excessive temperatures without subsequent humidification). In such cases, feed consumption could be affected.

Part of the problem could be solved by facilitating feed humidification in the feed mill or in the crop (for example: periods of darkness or continuous fasting exceeding 5-6 hours).

0-15 d

In general, it is recommended to use feeds in the form of high quality micropellets or crumbs, not excessively dry (DM < 90%) from 0 to 15 days of age. During the first days of life, the use of micropellets of 2 mm in diameter and length of less than 4 mm improves feed consumption and the growth of broiler chicks.

18-20 d

22-25 d

After 18-20 days of age, the bird accepts larger pellets (≤ 3 mm in diameter), and after 22-25 days pellets of 3.5 mm in diameter are appropriate.

The strict rules agreed for the percentage of fines require to grind the materials very finely and also apply an excess of hot steam, with temperatures reaching 90°C during the pelletizing process. This results in excessively hard granules, and feed consumption is reduced.


It should be noted that excessively hard crumbs (bright to the human eye), which are commonly observed when high levels of wheat are added to the formulation, can cause refusal of feed, particularly in young birds.

Besides feed refusal and increased feed wastage, the fine grindings and the excessive heat reduce nutrient digestibility, increasing the occurrence of wet litter. In practice, and under certain circumstances, coarse meals can be used from 21-25 days of age onwards. This will help to reduce growth rate and the occurrence of metabolic disorders associated wit carcass quality. It also can improve intestinal health, resulting in drier litter and, consequently, in lower incidence of breast ulcers and erosions, as well as hock burn.

31 nutriNews International August 2020 | The importance of feed presentation in broilers



The gizzard is a very powerful organ in the digestive system. The emptying of the gizzard, the harmonious digesta transit to the small intestine, and the higher intensity of antiperistaltic movements are largely dependent on gizzard functionality. An underdeveloped gizzard reduces HCl production in the proventriculus, which subsequently results in pH increase, impairing pepsinogen activation. Also, the gizzard is co-responsible for the production of enzymes and bile secretions in the GIT, which affects nutrient digestibility. Excess nutrients in the small intestine (particularly starch, due to the rapid passage of feed from the gizzard), a lower pepsin activity (due to the lack of HCl), and a reduction of antiperistaltic movements affect the digestibility. If antibiotics are not used as growth promoters, abnormal fermentations will occur in the large intestine, increasing the chances of suffering enteric disorders.


Therefore, in the presence of wet litter the use of coarse feeds improves carcass quality and allows for the reduction of antibiotic use. In any case, it should be noted that mash feeds affect the intake and, due to this, the birds will need 2 to 4 extra days to reach the weight required for slaughter.

32 nutriNews International August 2020 | The importance of feed presentation in broilers

The excess heat often increases digesta viscosity in feeds based on white cereals, which affects litter quality and the growth of broilers. The problem is reduced or even disappears with the use of enzymatic complexes. However, grain processing (fine grinding and heat application) could be beneficial in the case of feeds based on peas or vegetable protein concentrates, since it improves the digestibility of starch and protein fraction.

The use of other cereals, such as barley, does not seem to have the same beneficial effects (Bennett et al., 2002), but the reasons for these differences are not known. The fibrous edges of the barley grain can damage the structure of the mucosa and soft tissues, affecting the voluntary consumption.

The use of increasing amounts of whole wheat (5 to 25%) according to the age of the bird is a common practice in many European countries such as the Netherlands, Denmark, United Kingdom and Spain. The inclusion of wheat from 7 days of age improves the digestive physiology of broilers without significantly affecting feed consumption. Whole wheat (or in its absence cracked or coarsely ground corn) can improve the ability of the birds to defend against gastrointestinal infections, including clostridiosis, coccidiosis, and Salmonella spp. infections. In the case of using high percentages of wheat during the last week of life, the feed withdrawal period should be extended in order to facilitate the complete elimination of GIT contents before slaughter.


Heat processing of feed raw materials is commonly used in piglet diets, but not in poultry production. The application of high temperatures in cereals has little effect on the productive performance of the birds, except perhaps for chicks during the first days of life.

The effects of including whole grains, adding soluble fiber, providing mash feed, and using coarse particles on the intestinal health probably have in common their driving force for gizzard development. The gizzard is a very powerful organ, involved in intestinal peristalsis and in the proper functioning of the digestive system.

The importance of feed presentation in broilers


33 nutriNews International August 2020 | The importance of feed presentation in broilers



raw materials

lgae belong to the EU non-exhaustive positive list of raw materials for animal feeding, and

appears in different denominations:

Algae meals for algae, dried algae, algae meal, algae oil and algae extract. Algae meal produced from microalgae. Currently, algae are marginally used as raw materials for animal feeds due to their relatively high cost, However, they have been identified as important protein sources for the future. The animal nutrition sector needs to find alternative protein sources that can replace the traditional

Algae have been traditionally used in human nutrition for hundreds of years, particularly in Southeast Asia. Also, they are used as protein supplements in animal feeds or as fertilizers

ones such as soybean; algae can be an option. Besides, new additives such as natural pigments, carotenoids and polyunsaturated fatty acids that can improve the quality of animal products are also needed. The ban of the use of antibiotic growth promoters in January 1, 2016 forced the industry professionals to search for alternative natural solutions. Thanks to the prebiotic effects of algae oligosaccharides, algae can be part of the solution.

34 nutriNews International August 2020 | Use of algae in animal feeding – Ruminants

They also have been used in coastal regions, in poor and disadvantage areas, to feed animals. During the First World War, on the French Atlantic coast, animals were given algae due to the scarcity of oats and forage. The first studies on dietary supplementation of algae in animals intended for


human consumption (swine, poultry and horses) showed that algae have good acceptability, digestibility and assimilation. Other studies demonstrated the beneficial effects of the algae when they are added to the feed at levels of 5% to 10%. During a 20-year period (1960-1980), significant amounts of brown algae (Fucus and Sargassum

Macrocystis pyrifera is a species of brown algae that is used to form complexes with trace elements. Mixtures of sulfates with trace minerals such as copper, zinc, iron and manganese are dehydrated, passed through rollers, to obtain a crushed product..

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genus) were added to animal diets.


These products are called SQM and aim to improve the bioavailability of trace elements. The alginates, that are cell-wall constituents of the brown algae, are able to form chelates with divalent and multivalent ions. The stability of the complexes depends on the structure of the alginates. The glucoronate blocks (salts of glucuronic acid) form chelates, while the mannuronate blocks form complexes with alternative forms, and less stable. The trace elements are gradually released, according to the physicochemical conditions and the digestion stages.

35 nutriNews International August 2020 | Use of algae in animal feeding – Ruminants

ALGAE USED AS ANTHELMINTICS The use of certain algae as part of anthelmintic treatments includes: Alsidium helminthocorton, known as “Corsican moss”, act on pinworms and is used in dried or cooked form; Digenea is commonly used in Asia and Cuba, while Ulve durvillaea is used in New Zealand.

ASCOPHYLLUM NODOSUM Ascophyllum nodosum is a technological ingredient used as calcium sequestrant.

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The ion exchange (calcium replaced by sodium) occurs when the meal is dispersed in water and the rheological properties of the alginate are activated as thickener and gelling agent.


Two metabolites are responsible for the deworming or anthelmintic activity: the kainic acid (3-carboxymethyl-4-isopropenyl proline and domoic acid or 3-carboxymethyl-4- carboxymethyl hexa-1,3 diene), and the proline, both acids structurally close to the glutamic acid. The kainic acid and the proline are effective molecules against pinworms and roundworms.

Although they are currently only in marginal use due to the relatively high cost of raw materials, their nutritional properties and their ability to act as additives attract a lot of attention due to the presence of minerals, fiber, protein, vitamins and lipids, which put them at the leading edge of research and development.

MINERAL CONTENT Minerals can represent up to 36% of the dry matter. This fraction offers a great diversity: Macronutrients such as sodium, calcium, magnesium, potassium, chlorine, sulphur and phosphorus. Essential micronutrients such as iodine, iron, zinc, copper, selenium, molybdenum and other trace elements such as fluoride, manganese, boron, nickel and cobalt. Iodine is a special case, since studies in swine have demonstrated that the supplementation with 30 mg iodine/kg of feed resulted in increased iodine levels in muscles (from 23 to 138 mcg/kg). Similar results were observed in beef cattle and laying hens.

36 nutriNews International August 2020 | Use of algae in animal feeding – Ruminants

CAROTENOID CONTENT Algae contain carotenoid pigments, such as xantophylls (fucoxanthin, lutein and zeaxanthing) and carotene (β-carotene). Besides pigmentation, carotenoids have other properties; for example, they are used as powerful antioxidants capable of fixing oxygen and deactivating peroxide-rich radicals. The addition of carotenoid-rich algae to poultry diets improves egg yolk color.

FIBER CONTENT Total fiber content in algae varies between 32% and 50%. Within the insoluble fibers, there is a cellulosic fraction, which is present in low levels, particularly in red algae. The insoluble fiber is associated with the effects on the reduction of transit time through the colon. The soluble fiber fraction represents 51% to 56% of total fiber in green and red algae, and 67% to 87% in brown algae.

The soluble polysaccharides (agar, carrageenan and xylan) can be considered as the most important fraction for red algae (Gracilaria verrucosa, Chondrus crispus, Laver, Palmaria palmata). Agar and carrageenan are sulphate galactose and anhydrous galactose polymers. Xylans are neutral xylose polymers. In brown algae (Ascophyllum nodosum,

Fucus vesiculosus, Himanthalia elongata, Undaria pinnatifida), the soluble fibers are laminarans, alginates and fucans. Laminarans (β-glucans) are neutral glucose polymers. Alginates are polymers of mannuronic and glucuronic acids.

37 nutriNews International August 2020 | Use of algae in animal feeding – Ruminants

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In dairy cows, carotenoids reduce somatic cell count and improve the reproductive parameters, suggesting an improvement in the immune activity.

The soluble fiber is usually associated with hydration capacity, which (through absorption, retention and swelling) affects the bolus transit through the stomach and small intestine. They also have an impact on cholesterol and hypoglycemia


PROTEIN CONTENT The protein content in algae is variable The brown algae have a low protein content (5%-11% on a DM basis). Some red algae have protein contents varying between 30-40% on a DM basis, which is comparable to soybean. The green algae have a significant protein content that can reach 20% of their DM at certain times of the year.

1 Agar, carrageenan, ulvan and fucan are very soluble. 2 Laminaran xylans are totally degraded and immediately produce short chain fatty acids.

The spirulina or freshwater microalgae is well known for its high protein content (70% on a DM basis). A mixture of green algae was included in broiler diets (at a 10% level) and this resulted in a higher daily weight gain.

raw materials

3 Alginates are partially degraded, resulting in the formation of elimination oligomers: the β-oligomers have showed prebiotic effects in rats (in vitro and in vivo), which can be seen as an opportunity for field application. The oligosaccharides are saccharide polymers that have prebiotic properties related to colon microbial flora.

VITAMIN CONTENT Despite seasonal variations, the vitamin composition of algae indicates that the vitamin content is a relevant parameter, which can be seen by: Levels of provitamin A (red algae) Levels of vitamin C (brown and green algae)

The oligosaccharides can be added to the feed to block bacterial colonization in many portions and stimulate intestinal immune response.

Levels of vitamin E (brown algae)

Vitamins of the B complex are found in significant amounts (particularly B2 and B3). The high levels of vitamin B12 represent an advantage over land plants, which are totally deficient. 38 nutriNews International August 2020 | Use of algae in animal feeding – Ruminants

LIPID CONTENT The lipid content in algae is very low: 1%-3% on a DM basis. The lipid content in Ascophyllum nodosum can reach 5%. In qualitative terms, lipids from algae differ from lipids from land plants.


The predominant acids are the unsaturated fatty acids. The green algae have a fatty acid composition closer to that of land plants, with a much higher content in oleic acid (C 18: 1) and alpha-linolenic acid (ω3 – C18: 3).

The use of marine algae in animal diets improves overall health and animal performance.

The red algae have high levels of 20-carbon polyunsaturated fatty acids. This is a unique characteristic in the plant kingdom, as these fatty acids are frequently found in the animal kingdom.

The skin quality is improved, the estrous cycle is normalized, sperm quantity and quality are increased, and, therefore, conception and birth rates are improved.

In the brown algae, there is a similar distribution of fatty acids, although the content of linolenic acid is high.

It is interesting to consider Ascophyllum as an iodine source, since the foodstuffs for human consumption (meat, milk and eggs) should contain adequate iodine levels to ensure the metabolic requirements of the population.

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The levels of eicosapentaenoic acid (EPA, ω3 – C20: 5) are particularly high, up to 50% of polyunsaturated fatty acids in the genus Porphyra. The arachidonic acid (ω6 – C20: 4) is also present. The 18-carbon polyunsaturated fatty acids reach levels of 10% of total fatty acids in Porphyra.

Besides being used as a corrective of soil acidity in agriculture, Lithothamnium or maerl is a very interesting alternative for animal feeding, especially for ruminants. Improves the synthesis of rumen microflora Promotes nutrient assimilation Corrects excess acidity in animals fed diets containing high levels of corn silage, reducing the risk of acidosis. Helps meet calcium needs caused by milk production. Contains 0.27% sulphur, which plays an essential role in the synthesis of sulphurated amino acids and, in turn, proteins, vitamins and redox control in the rumen. The digestive use of marine magnesite is approximately 75%, which demonstrates that its ingestion does not cause any metabolic disorder.

39 nutriNews International August 2020 | Use of algae in animal feeding – Ruminants

THE SPIRULINA AND THE COMMERCIAL USE OF MICROALGAE CULTIVATION These primitive aquatic organisms reproduce by simple division, once or twice a day, and are considered as the most productive plants in the world. Spirulina spp. is among the most well-known edible microalgae.

The commercial use of these cultivations represents an advance for the food industry in general, and for the feed industry in particular, since microalgae are protein sources with possible applications in this sector due to their high protein value. The studies consulted show an enormous variability of the composition, with varying proportions of protein, fatty acids and carbohydrates. This shows the advantage of including algae in diets fed to different animal species.

Spirulina is an important source of nutritional compounds of high biological value. It has been known for centuries by populations from many countries such as China, Greece and Mexico.

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Rich in chlorophyll and phycocyanin Polyunsaturated fatty acids (PUFA), mainly of the n-3 series, such as the docosahexaenoic acid (DHA). Also, it is an interesting source of acids acting as a precursor for gamma-linolenic acid, prostaglandins, leukotrienes and thromboxanes. Antioxidants such as phycocyanin and carotenoids, which can act as provitamin A and prevent the formation of reactive oxygen species (contributors of oxidative stress that lead to chronic diseases such as cancer, and also aging). Vitamins (it has almost all the essential compounds), including vitamin A, vitamin B and tocopherols. A peculiar finding for an herbal product is that the spirulina contains vitamin B12, showing a close phylogenetic liaison between these algae and the bacteria that produce the vitamin. Minerals: macro minerals (Na, K, Ca and Mg) and micro minerals (Fe, Zn, Mn and Cu). Due to the biologically active substances mentioned above, spirulina has been added to feeds for rabbits, swine, poultry, fish and ruminants.


60%-70% protein and all the essential amino acids, highly bioavailable

The main advantage of the microalgae is their amino acid profile, which, in some of the examined species, is comparable to the best traditional protein sources. Microalgae also have high levels of vitamins and trace elements, besides a low ash content. The species of microalgae differ in composition and in the forms of use and treatment, depending on the animal species. Several field trials have been carried out in aquaculture species, since the most frequent applications of microalgae in animal feeds are observed in this sector. Studies in poultry have also been consulted, which show that inclusion levels of 5%-10% can be safely used to replace traditional protein sources. Currently, researches have been focusing on the physyco-chemical characterization and the nutritional assessment of different microalgae strains. Ruminant feeding is an interesting field to explore. Recent studies suggested that the supplementation with algae cause a selection of protozoan populations in the rumen, thus affecting the proportion of short chain fatty acids. It is also known that the inclusion of high amounts of algae in the concentrate can affect animal performance and reduce the intake. For this reason, further studies are needed to determine at what dosis the beneficial effects are maintained without affecting performance.

40 nutriNews International August 2020 | Use of algae in animal feeding – Ruminants

These fatty acids are absent or reduced to a minimum level in traditional diets fed to dairy cows, while they are present in very low levels (less than 0.1%) of total fatty acids in dairy products. The studies on spirulina in dairy cows have showed positive results which have a direct impact on productivity: The animals fed spirulina had an increase of 21% in milk production. Also, increases in milk fat (between 17.6% and 25.0%), milk protein (9.7%) and lactose (11.7%) were observed in cows fed microalgae, compared with controls. These results can be attributed to the influence of spirulina on the synthesis of microbial protein, the reduction of rumen degradation, and also to its composition that is rich in nutrients. Moreover, these results highlight the positive effects of spirulina on the health of dairy cattle. The use of spirulina has been associated with a significant reduction in the somatic cell count, which improves milk nutritional value. Also, the animals fed spirulina showed better body condition compared with controls.

Studies in bulls demonstrate that their sperm quality improves when spirulina is added to the diet. Sperm motility, concentration and viability after storage were positively affected by the algae. However, further studies are needed to better understand the relationship between sperm quality and the addition of spirulina to the diet.

Use in small ruminants The knowledge about the effects of spirulina on ovine products and productivity remains a relatively unexplored field. Very few studies have been published in this area: In one of the studies, lambs given milk from sheep fed spirulina showed higher live weight and higher daily weight gain compared with controls. Also, lambs had higher birth weight when the sheep were fed spirulina during pregnancy.

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APPLICATION OF SPIRULINA IN RUMINANTS It is known that milk and dairy products are currently used as functional foods. Therefore, the attention has been focused on the enrichment of milk fat with PUFA. These acids, which cannot be synthesized by humans and animals, have beneficial effects, mainly the n-3 series. They can protect against cardiovascular disease, atherosclerosis. skin diseases and arthritis.

It thus seems clear that algae can bring benefits when added to animal diets. They can be used as direct raw materials for utilization of their different nutrients, as well as a source of compounds of prebiotic action. There is a clear need for further studies that instigate the use of algae in ruminant production.

OTRAS APLICACIONES DE LA ESPIRULINA Calidad del esperma en toros

Use of algae in animal feeding - Rumiants


41 nutriNews International August 2020 | Use of algae in animal feeding – Ruminants

Carlos Fernรกndez1, Fernando Bacha2, 1 Polytechnic University of Valencia 2 NACOOP S.A., Madrid



The aim of this trial is to reduce the protein content of dairy goat diets in order to decrease the excretion of N in faeces and urine.


Animals: Goats from the Murciano-Granadina breed were used as a model for ruminant animals during the mid-lactation period (43 kg average live weight). Housing: The facilities belong to the Polytechnic University of Valencia. Metabolic cages were used to establish the nitrogen balance and to quantify the nitrogen ingested, excreted in faeces and urine, and retained in the body and milk. To determine the in vivo gas emissions in each animal, an open circuit indirect calorimetry system described by Fernรกndez et al. was used (2012; 2015).

Experimental design: Mixed rations were prepared in a concentrated fodder ratio of 40/60, the fodder being alfalfa hay. One of the rations had 19% crude protein (CP) and the other one had 15% CP. 40 goats were fed with the high-CP diet and 65 goats were fed with the low-protein diet.

42 nutriNews International August 2020


The greenhouse gases (nitrous oxide [N2O], carbon dioxide [CO2] and methane [CH4]), expressed in CO2 equivalents, are presented in Table 1. The N2 was estimated according to HACCP, 2006.





kg CO2 eq/day (N2O)





kg CO2eq/day (CO2)





kg CO2eq/day (CH4)





kg CO2eq/goat/day





kgCO2eq/kg milk





19% CP

15% CP

*SD = standard deviation of the average

Table 1. Carbon footprint of dairy goats fed with rations different levels of crude protein.

A lower emission, expressed in kg of CO2 eq, coming from the CO2 and N2O gases was associated to the low CP ration. This reduction in gases was not followed by a reduction in CH4 gas. Regarding the CO2 eq originating from methane, a possible explanation would be the high fibre content of the low-CP ration. The kg of CO2 eq per goat per day was lower in the low-CP ration (1.91 vs. 2.17), and if we express this amount per kg of milk, no differences are observed between the diets (1.0 kgCO2 e/kg milk, on average).


The reduction of the CP of the ration by 4 points led to a reduction of 0.26 kg of CO2 eq per goat per day. The present study is a theoretical approximation with values determined in the trial conditions and using the individual goat as a model. In other words, the herd and the type of farm have not been evaluated and therefore do not include emissions from the farm or its daily management (electricity, transport, gas, petrol, purchase of food, etc.).

43 nutriNews International August 2020

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