‘Jersey – The Most Profitable and Sustainable Cow?’ – Literature Review for Jersey Australia
Executive Summary This review has found that the Australian Jersey has several attributes compared with other breeds used in the Australian dairy industry that may contribute to the profitability and sustainability of Australian dairy farm businesses. These attributes include higher fertility, higher production efficiency, greater heat tolerance and longevity. The main findings are summarised in Table 1. Table 1. Main findings of this review. Aspect Main findings 1 Milk yield, • Holsteins produce more milksolids per cow per year than Jerseys composition and • The composition of milk differs between breeds, but many other factors market also influence it suitability • Fat and protein concentrations in milk of Jerseys are higher than those of Holsteins by about 1.1-1.4 g/100ml and 0.5-0.56 g/100ml respectively • The concentrations of fatty acids in milk fat differ between breeds but are small relative to those between different stages of lactation • Jersey milk fat contains a higher proportion of short and medium-chain fatty acids and a lower proportion of C16:1, C18:1, and conjugated linoleic acid • There is insufficient evidence to determine whether Jerseys are more or less susceptible to milk fat depression than Holsteins under the same feeding management and environmental conditions • The amino acid (AA) profile of Jersey milk does not differ significantly from other breeds • Jersey milk has higher concentrations of calcium, phosphorus and zinc than Holstein milk, and a lower concentration of potassium 2 Production • Jerseys produce 6-11% more energy-corrected milk (ECM) than Holsteins efficiency per kilogram of dry matter intake, and 26-31% more ECM per 100 kg bodyweight than Holsteins. Jerseys are 8% more energetically efficient • Jersey cows’ higher production efficiency is due to reduction and dilution of their daily maintenance energy requirement • Jerseys appear to be performing well in mixed breed herds. However, Jerseys in straight Jersey herds produce more milk solids per year than Jerseys in mixed-breed herds 3 Feed intake, • Jerseys have about 14-21% higher feed intake capacity than Holsteins per eating behaviour 100 kg bodyweight and 5% per unit metabolic bodyweight. This may be due and nutrient to their larger gastrointestinal tract per kg body weight, higher rate of digestibility particle breakdown within the rumen and higher fractional outflow rate of digesta from the rumen • Jerseys spend more time grazing and ruminating per unit of ingested feed and distribute meals more evenly throughout each 24-hour period than Holsteins, providing a more regular supply of feed to the rumen • Several studies have found that Jerseys have higher NDF digestibility than Holsteins, despite their higher gut passage rate • A recent study indicates that Jersey cows are more efficient at utilising dietary nitrogen than Holsteins 4 Fertility • Jerseys have higher fertility than Holsteins. This is likely to be due to genetic selection and energy metabolism, particularly in the transition period and early lactation, in which Jerseys remain in negative energy balance (NEB) for a shorter period of time relative to Holsteins and the magnitude of Jerseys’ NEB is less than that of Helsteins • The mean daughter fertility breeding value for sires of Jersey cows has been flat or declining for four decades, whereas that of sires of Holstein cows is now increasing. If these trajectories continue, the fertility advantage of Jerseys over Holsteins may be reduced +
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Prepared by Dr Steve Little, Capacity Ag Consulting, 1 November 2021
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