日粮维生素A添加量对秦安杂交肉牛牛肉品质的影响

摘要

A slaughter trial was conducted to evaluate the effects of dietary vitamin A supplementing dose on meat quality by using 16 Angus× Qinchuan crosses steers at 24-month age in a complete randomized design after 4 months of finishing period with diets contained 0,1100,2200 and 4400 IU/kg DM. The results showed that VA dose did not affect subcutaneous fat thickness,mesenteric fat weight/living weight,longissimus area,dressing percentage,pure meat percentage and marbling score (P>0. 05) which was better with the decrease of VA dose. But VA dose significantly affected final weight,daily gain,back fat thickness and shear force(P<0. 05) , back fat thickness and shear force were lowest at 1100 IU/kg DM, and average daily gain which had a tendency was numerically greater with VA dose increment when dietary YA dose was less than 2200 IU/kg DM. VA dose had no significant effect on the chemical composition of LD and GM except for matter and crude ash of GM, matter and crude protein of LD(P>0. 05). VA dose had significant effect on drip loss, total pigment concentration and TBARS during aging(P<0. 05) , and different beef cuts responses to VA dose were not identical. Considering these results, the effect was the best when the Angus× Qinchuan steers were fed with the diet contained VA 1100 IU/kg DM.%为了研究日粮维生素A(vitamin A)添加量与肉牛牛肉品质的关系,选用16头24月龄安格斯×秦川黄牛阉牛,以添加0、1100、2200、4400 IU/kg干物质VA的日粮育肥4个月后屠宰分析不同日粮VA添加量对肉牛屠宰性能和牛肉品质的影响.试验结果表明,①在肉牛屠宰特性方面,VA添加量对肉牛屠宰率、净肉率、肠系膜脂肪质量/活体重、大理石花纹评分和眼肌面积均无显著影响(P＞0.05)；VA添加量显著影响肉牛末期体重、日增重、背部皮下脂肪厚度、肋部皮下脂肪厚度和肉品剪切力(P＜0.05),其中日增重以2200 IU/kg干物质VA添加量时最高,低于此添加量则有随VA添加量升高而增加的趋势,而背部皮下脂肪厚度和剪切力均以1100 IU/kg干物质VA添加量时最低；②在肉品常规成分(以鲜样为基础)方面,日粮VA添加量显著影响背最长肌干物质及粗蛋白含量和臀中肌干物质及粗灰分含量(P＜0.05),而对背最长肌粗脂肪及粗灰分含量和臀中肌粗蛋白和粗脂肪含量无显著影响(P＞0.05)；③在牛肉氧化稳定性方面,VA添加量对吊挂成熟的背最长肌和臀中肌的总色素含量、硫代巴比妥酸反应物值(TBARS)和滴水损失均有显著影响(P＞0.05).其中,总色素含量在背最长肌和臀中肌均以1100 IU/kg干物质VA添加量时最高,TBARS值在背最长肌以2200 IU/kg干物质VA添加量时最低,在臀中肌以1100 IU/kg干物质VA添加量时最低.综合各方面结果,在该试验条件下,以1100 IU/kg干物质VA添加量饲喂秦安杂交阉牛的效果较好.