In bulls, with a genetic predisposition for leanness and reared in a grass-based production system dietary fish oil may further enhance the nutritional value of beef by increasing the concentration of the omega 3 polyunsaturated fatty acids (PUFA), eicosapentanoic acid (EPA) and docosahexanoic acid (DHA). The impact of including rumen protected fish oil in the finishing diet of late maturing breed bulls on their growth, feed efficiency, carcass fat classification, aspects of ultimate meat quality and the fatty acid composition of the M. Longissimus thoracis muscle (LT) was examined. Twelve month old bulls were supplemented with a barley-based concentrate (500g/kg dietary dry matter) from turn-out to pasture in spring until housing 94 days later. Bulls were housed indoors and offered ad libitum, either the same concentrate or a concentrate containing rumen protected fish oil (PFO) at a ration fat concentration of 50g/kg dry matter, along with grass silage to appetite, for 88 days pre-slaughter. Inclusion of PFO increased (P<0.05) concentrate consumption, but this was not reflected in carcass growth, classification or fat colour or in LT colour or tenderness. Concentrations of 18:2, EPA, DHA, total PUFA and the PUFA: saturated fatty acid ratio (0.19 v 0.14) were higher (P<0.05) in LT from PFO compared to control bulls. The increase in EPA + DHA, associated with PFO inclusion, from 7 to 12 mg/100g muscle is below the concentration required by European Commission regulations (40 mg/100g) to allow this beef to be labelled a “source of” EPA + DHA. Nevertheless, consuming beef from PFO bulls would make a greater contribution to the daily consumer requirement for omega-3 PUFA than beef from the control bulls. This has potential to add value to beef from the PFO production system.

在公牛中，具有瘦肉的遗传易感性，并在以草为基础的生产系统中饲养，通过增加ω3多不饱和脂肪酸（PUFA），二十碳五烯酸（EPA）和二十六碳六烯酸（DHA）。研究了在后期成熟的公牛的最终饮食中加入瘤胃保护鱼油对其生长，饲料效率，car体脂肪分类，最终肉质方面以及M. Longissimus胸廓肌（LT）脂肪酸组成的影响。。从春季到牧场，直到94天后饲养，对十二个月大的公牛都补充了大麦基浓缩物（500g / kg饮食干物质）。公牛被安置在室内并随意提供，在屠宰前88天，应将相同的浓缩物或浓缩饲料中浓度为50g / kg干物质的瘤胃保护鱼油（PFO）以及草青贮饲料食入浓缩物。包含PFO增加了（P <0.05）精矿消耗量，但未在car体生长，分类或脂肪颜色或LT颜色或嫩度中反映出来。与公牛相比，来自PFO的LT中18：2，EPA，DHA，总PUFA的浓度以及PUFA：饱和脂肪酸的比例（0.19 v 0.14）更高（P <0.05）。与PFO包埋有关的EPA + DHA的增加从7mg增加到12mg / 100g肌肉，低于欧盟委员会规定的允许浓度（40 mg / 100g）以使这种牛肉被标记为EPA + DHA的“来源” 。不过，食用来自PFO公牛的牛肉将比来自控制公牛的牛肉对omega-3 PUFA的每日消费者需求做出更大的贡献。这有可能通过PFO生产系统为牛肉增值。