营养水平及性别对生长育肥猪肉质性状发育规律的影响

研究了高低营养水平对长×荣杂交猪肉质性状发育影响。高低营养水平的饲粮消化能分别为 14 2和 12 0MJ/kg ,高营养水平组 2 0～ 5 0kg、5 0～ 80kg和 80～ 10 0kg阶段的饲粮蛋白质含量分别为 18%、15 5 %和 13 2 % ,低营养水平组相应为 15 5 %、13 2 %和 11 2 %。 90头试验猪随机分配到 2个处理中 ,每组 3个重复。当猪的体重分别达到 2 0kg、35kg、5 0kg、80kg和 10 0kg时 ,每重复各取 1头猪进行屠宰 ,测定屠宰性能和猪肉品质。结果表明 ,随着体重的增加 ,背脂厚、眼肌面积、肌间脂肪、失水率、肌肉次黄嘌呤核苷酸和胶原蛋白含量呈二次曲线上升 ,肌纤维面积呈线性上升 ,而瘦肉率和肌肉水分含量呈二次曲线性下降。肉色评分除 2 0kg较低外 ,全期变化不大。营养水平明显影响背脂厚、肌肉水分含量、肌内脂肪含量和失水率 (P <0 0 5或 0 0 1)。与高水平比较 ,低水平明显降低背膘厚、提高肌肉水分含量、降低肌内脂肪含量和失水率 (P <0 0 5 )。营养水平对其他肉质指标无明显影响。性别对肉质指标的影响还需进一步研究

Influences of Nutritional Levels and Sex on the Development of Pig Meat Traits

This study is to investigate the growth development of pigmeat traits at high (HL) and low (LL) nutritional levels. 90 Landrace×Rongchang barrows with 18?kg bodyweight (BW) were randomly allotted into two treatments with 3 replicates each. Pigs were fed with diets containing DE 14 2?MJ/kg and CP 18%, 15 5% and 13 2% for the stage of 18～50, 50～80 and 80～100?kg respectively (HL) or diets with DE 12 0?MJ/kg and CP 15 5%, 13 2% and 11 2% for each stage (LL). For each treatment, 3 pigs were killed at 20, 35, 50, 80 or 100?kg BW to examine meat measurements. The amount (kg) of lean deposition (=0 4156+0 3299 BW (kg), R 2=0 9997, P<0 001), but didn't vary with nutritional levels (P>0 05). Backfat thickness, logissimus muscle (LM) area, intramuscular fat (IMF) content, water loss (WL) of meat, inosine monophosphate (IMP) and collagen content were increased quadratically, myofibril intersectional area increased linearly, and lean percentage (LP) and pork moisture content decreased quadratically as BW enhanced. Color score didn't change significantly with BW. Backfat thickness, moisture content, IMP and water loss were influenced by nutritional levels. There were lower backfat thickness, higher moisture content, and lower IMF content and water loss in LL compared to HL. Other meat traits were not affected by nutritional treatment. The influence of sex on meat quality needs to be further studied.