不同饲养方式对鲁莱黑猪生产性能及肌红蛋白含量影响的研究

Effects of different feeding methods on production performance and myoglobin content in Lulai black pigs

为了探索鲁莱黑猪科学的饲养方法,试验将28头80日龄鲁莱黑猪随机分为圈养组和放养组,每组14头,测定80,210,240,270日龄体重,以及80~210日龄、211~240日龄、241~270日龄平均日增重、日耗料量、料重比,在210,240,270日龄各组选取3头进行屠宰,测定胴体重、胴体长、背膘厚、皮厚、眼肌面积、屠宰率、熟肉率、系水率、滴水损失、嫩度、pH值、肌红蛋白含量及肉色(L^(*)值、a^(*)值、b^(*)值)指标。结果表明:270日龄时,圈养组鲁莱黑猪体重显著高于放养组(P<0.05),其他阶段圈养组与放养组体重差异不显著(P>0.05)。圈养组和放养组均是在80~210日龄时的平均日增重最高,圈养组达492.64 g,放养组达469.14 g;圈养组在80~210日龄时的料重比最低,为4.83。210日龄时,放养组的胴体重、胴体长、背膘厚、眼肌面积略低于圈养组(P>0.05),屠宰率略高于圈养组(P>0.05),皮厚与圈养组差异不明显(P>0.05);240日龄时,放养组的胴体长、背膘厚、皮厚低于圈养组(P>0.05),胴体重、屠宰率略高于圈养组(P>0.05),眼肌面积显著高于圈养组(P<0.05);270日龄时,放养组胴体重、背膘厚略低于圈养组(P>0.05),胴体长、皮厚显著低于圈养组(P<0.05),眼肌面积、屠宰率显著高于圈养组(P<0.05);圈养组和放养组的熟肉率、系水率、嫩度、pH值3个日龄间差异不显著(P>0.05)。在圈养组中,210日龄的胴体重、胴体长低于240日龄(P>0.05)和270日龄(P<0.05),背膘厚、皮厚、眼肌面积、屠宰率3个日龄间差异不显著(P>0.05),屠宰性能指标总体呈270日龄>240日龄>210日龄;270日龄的肌红蛋白含量(0.716 mg/g)最低,240日龄含量最高(0.831 mg/g);肉色L^(*)值、b^(*)值随日龄的增加呈先降后升的趋势,a^(*)值呈先升后降的趋势。在放养组中,210日龄的胴体重、胴体长均显著低于240,270日龄(P<0.05);210日龄的眼肌面积低于240日龄(P>0.05)和270日龄(P<0.05);210日龄的肌红蛋白含量(0.784 mg/g)最低,270日龄最高(0.986 mg/g);肉色L^(*)值、b^(*)值随日龄的增加而逐渐降低,a^(*)值逐渐增加。说明随着饲养时间延长,屠宰性能指标总体呈递增趋势,但肉品质指标不一定最优;综合养殖成本及屠宰性能指标,圈养鲁莱黑猪的最佳屠宰期为240日龄,放养鲁莱黑猪为270日龄。

In order to explore the scientific feeding methods of Lulai black pigs,28 Lulai black pigs of eight days old were randomly divided into captive group and grazing group,with 14 pigs in each group,respectively.The body weight of 80,210,240,270 days of age,and the average daily gain,feed consumption,feed-to-meat ratio of 80-210,211-240,241-270 days of age were determined.At 210,240 and 270 days of age,three pigs in each group were selected for slaughter,and carcass weight,carcass length,back fat thickness,skin thickness,eye-muscle-area,slaughter-rate,cooked meat rate,water-keep rate,drip loss,tenderness,pH value,myoglobin content and flesh color(L^(*),a^(*)and b^(*)value)indexes in Lulai black pigs were determined.The results showed that the daily gain in the capative group was significantly higher than that in the grazing group at 270 days of age(P<0.05),but there was no significant difference in body weight between the two groups at other stages(P>0.05).At the age of 80-210,the average daily gain was highest in the capative group and the grazing group,reaching 492.64 g in the captive group and 469.14 g in the the grazing group.The ratio of feed to meat in capative group was the lowest at the age of 80-210,which was 4.83.At 210 days of age,the carcass weight,carcass length,backfat thickness and eye muscle area in the grazing group were slightly lower than those in the capative group(P>0.05),while the slaughter rate was slightly higher than that in the captive group(P>0.05).There was no significant difference in skin thickness between the two groups(P>0.05).At 240 days of age,the carcass length,backfat thickness and skin thickness in the grazing group were lower than those in the captive group(P>0.05),while the carcass weight and slaughter rate in the grazing group were lower than those in the captive group(P>0.05),eye muscle area was slightly lower than that in the captive group(P<0.05).At 270 days of age,the carcass weight and backfat thickness in the grazing group were lower than those in the captive group(P>0.05),carcass length and skin thickness were slightly lower than that in the captive group(P<0.05),while eye muscle area and slaughter rate were higher than those in the captive group(P<0.05).There were no significant differences between the captive group and the grazing group in cooked meat rate,system water rate,tenderness and pH value at 3 days of age(P>0.05).In the captive group,carcass weight and carcass length were significantly lower at 210 days of age than at 240 days of age(P>0.05)and 270 days of age(P<0.05),back fat thickness,skin thickness,eye muscle area and slaughter rate were not significantly different(P>0.05),and slaughter performance indicators generally showed 270 days of age>240 days of age>210 days of age,and the myoglobin content(0.716 mg/g)in the capative group was the lowest at 270 days of age and the highest at 240 days of age(0.831 mg/g),and the L^(*)and b^(*)values of meat color in the captive group decreased first and then increased with the increase of age,while the a^(*)increased first and then decreased.In the grazing group,carcass weight and carcass length were significantly lower at 210 days of age than at 240 and 270 days of age(P<0.05);eye muscle area was lower at 210 days of age than at 240(P>0.05)and 270 days of age(P<0.05),and the myoglobin content(0.784 mg/g)in the grazing group was the lowest at 210 days of age and the highest at 270 days of age(0.986 mg/g),and the L^(*)and b^(*)value of meat color in the grazing group decreased gradually with age,while a^(*)value increased gradually.The results indicated that slaughter performance indicators tend to increase overall with increasing rearing time,but meat quality indicators are not necessarily optimal,and combining the cost of breeding and slaughter performance indicators,the optimal slaughter period was 240 days of age for the captive Lulai black pigs and 270 days of age for the grazing Lulai black pigs.