Comparative responses to sodium selenite and organic selenium supplements in Belgian Blue cows and calves

Belgian Blue (BB) beef cattle is particularly prone to selenium (Se) deficiency due to the poor Se content of soil and roughages on rearing farms and the higher requirements of this hypermuscled breed. The goal of this trial was to compare the effects of different forms and concentrations of Se supplementation on Se status, health and performance in 60 pregnant Se-deficient BB cows. Cows were allocated to 3 experimental groups receiving selenized-yeast at 0.5 ppm Se on total ration (Y–Se 0.5), Na–selenite at 0.5 ppm Se on total ration (Na–Se 0.5) and Na–selenite at 0.1 ppm Se on total ration (Na–Se 0.1), respectively. Cows were supplemented from 2 months before calving until 2 months after calving. Data on performance, health and Se status of the dams and their calves were analyzed using a linear model, least squares means and logistic regression. At the end of the study, plasmatic Se (pSe) was significantly higher (P < 0.01) in cows receiving Y–Se than in cows from other groups. Glutathion-peroxidase in erythrocytes (GSH-pxe) was higher in Y–Se and Na–Se 0.5 than Na–Se 0.1 group (P < 0.01). Se content in colostrum and milk was significantly higher (P < 0.01) in Y–Se than other groups. At birth, Se status of calves from group Y–Se was significantly higher than those of other groups (P < 0.01). Plasmatic Se in calves remained higher for 75 days after birth in Y–Se compared to other groups (P < 0.01). Diarrhoea was the most commonly observed disease in the calves and, during the first 15 days of life, diarrhoea occurred in 6%, 21% and 35% of calves from groups Y–Se, Na–Se 0.5 and Na–Se 0.1, respectively. Over the whole 75 days trial period, incidence of diarrhoea was 19, 29 and 65%, respectively. Average daily gain (ADG) in calves born from Y–Se group of cows tended to be higher than in Na–Se 0.5 (P = 0.06) and Na–Se 0.1 (P < 0.05) but there was no difference between Na–Se 0.5 and Na–Se 0.1 (P > 0.1). At the same dosage, Y–Se conferred better Se status in both dams and their calves than did Na–Se. Requirement of 0.1 ppm Se seems to be insufficient in BB to optimise health and performance. Regarding health status and ADG in calves, Y–Se seems also to result in better performance.     

精粗比条件下新疆芦苇在断奶初期奶公犊瘤胃内动态降解的研究

选用3头三月龄左右装有瘤胃瘘管的荷斯坦公犊,按3×3完全拉丁方试验设计,喂给三种日粮,日粮组成按精粗比分别表示为:Ⅰ:70∶30;Ⅱ:60∶40;Ⅲ:50∶50,研究不同日粮组成下新疆芦苇的DM、CP以及NDF在断奶初期奶公犊瘤胃内动态降解。结果表明:精粗比为60∶40日粮时,其CP的消失率和降解参数显著低于精粗比为70∶30和50∶50的日粮(P<0.05);其DM和NDF的消失率和降解参数显著高于精粗比为70∶30和50∶50的日粮(P<0.05)。     

饲料营养对猪肉品质的影响

对影响猪肉品质的主要营养因素:能量、脂肪和脂肪酸、蛋白质和氨基酸、维生素、矿物质元素及其它饲料添加剂的饲养试验效应进行了综述,并提出了今后有待解决的问题.     

Disposition kinetics and dosage regimen of levofloxacin on concomitant administration with paracetamol in crossbred calves

The disposition kinetics of levofloxacin was investigated in six male crossbred calves following single intravenous administration, at a dose of 4 mg/kg body weight, into the jugular vein subsequent to a single intramuscular injection of paracetamol (50 mg/kg). At 1 min after the injection of levofloxacin, the concentration of levofloxacin in plasma was 17.2 ± 0.36 µg/ml, which rapidly declined to 6.39 ± 0.16 µg/ml at 10 min. The drug level above the MIC₉₀ in plasma, was detected for up to 10 h. Levofloxacin was rapidly distributed from blood to the tissue compartment as evidenced by the high values of the distribution coefficient, α (17.3 ± 1.65 /h) and the ratio of K₁₂/K₂₁ (1.83 ± 0.12). The values of AUC and Vd_area were 12.7 ± 0.12 µg.h/ml and 0.63 ± 0.01 l/kg. The high ratio of the AUC/MIC (126.9 ± 1.18) obtained in this study indicated the excellent antibacterial activity of levofloxacin in calves. The elimination half-life, MRT and total body clearance were 1.38 ± 0.01 h, 1.88 ± 0.01 h and 0.32 ± 0.003 l/kg/h, respectively. Based on the pharmacokinetic parameters, an appropriate intravenous dosage regimen for levofloxacin would be 5 mg/kg repeated at 24 h intervals when prescribed with paracetamol in calves.     

The Effect of Gender on Slaughtering Performance and Meat Quality in Sunite Sheep

The purpose of this experiment was to study the effect of gender on the slaughter performance and meat quality of Sunite sheep.Twelve 6-month-old Sunite rams and ewes at the same body condition were selected from the grazing herds of the Sunite Zuoqi Improvement Station Breeding Farm to determine their slaughter performance and meat quality.The slaughter test results showed that the bone quality and bone-meat ratio of the rams were significantly higher than that of the ewes (P<0.05),and the net meat quality and net meat rate of the ewes were significantly higher than that of the rams (P<0.05).The results of meat quality traits showed that the drip loss of ewes were significantly lower than that of rams (P<0.05),and the other indicators were not significantly different (P>0.05).The results of conventional nutrient composition of muscles showed that the intramuscular moisture content of the rams were significantly higher than that of the ewes (P<0.05),and the intramuscular fat content of the ewes were significantly higher than that of the rams (P<0.05),while the other indicators were not significantly different (P>0.05).The results of amino acid determination showed that the essential amino acid ratio in muscle of sunite ewes were significantly higher than that of rams (P<0.05),but there was no significant difference between the rams and ewes that formed the precursor amino acid content of meat flavor (P>0.05).Fatty acid measurement results showed that the saturated fatty acid ratio in the subcutaneous fat of rams was significantly lower than that of ewes (P<0.05).There was no significant difference in the ratio of saturated fatty acids in muscle fat and tail fat (P>0.05);The ratio of monounsaturated fatty acids in ewes tail fat was significantly higher than that of rams (P<0.05).The ratio of monounsaturated fatty acids in subcutaneous fat and intermuscular fat was not significantly different between rams and ewes (P>0.05).The ratio of polyunsaturated fatty acids in intermuscular fat of rams was significantly higher than that of ewes (P<0.05),and there was no significant difference in the content of polyunsaturated fatty acids in subcutaneous fat and tail fat (P>0.05).In summary,it showed that gender had a certain influence on the slaughter performance and meat quality of 6-month-old Sunite sheep.     

Effect of Supplementing Alfalfa Powder to Diet on Growth Performance and Meat Quality of Goose

The experiment was aimed to investigate the effects of dietary alfalfa powder on the growth performance,body size,slaughter performance,organ index and meat quality of Siji geese.A total of 256 15-day-old geese (half male and half female) with similar body weight were randomly divided into four groups with 4 replicates of 16 geese each.The geese in control group were fed with corn-soybean meal-based diet (control diet),and geese in the experimental groups were fed the basal diet replaced with 10%,20% and 30% alfalfa powder,respectively.The results showed that,compared with the control group,dietary alfalfa powder supplementation had no significant effect on the average daily intake,average daily gain,feed conversion ratio,body oblique length,keel length,shin circumference,semi diving length,chest width and shin length (P>0.05),and also had no effect on the carcass ratio,half-eviscerated carcass ratio and pectoral muscle ratio (P>0.05).However,dietary 20% and 30% alfalfa powder supplementation significantly increased the chest depth (P<0.05),dietary 30% alfalfa powder significantly decreased the full-eviscerated carcass ratio (P<0.05),and dietary 10% alfalfa powder significantly increased the leg muscle ratio (P<0.05) of geese.In addition,dietary alfalfa powder significantly decreased the abdominal fat ratio (P<0.05),raised the growth index of liver,jejunum,ileum,and cecum (P<0.05),and increased the water loss rate of pectoral muscle and leg muscle (P<0.05) compared with the control group.Dietary 10% and 30% alfalfa powder significantly increased duodenal growth index (P<0.05) of geese.In conclusion,dietary alfalfa powder supplementation might improve the slaughter performance (increase chest depth and leg muscle ratio,reduce abdominal fat rate) and organ growth index (increase the growth index of liver,duodenum,jejunum,ileum and cecum).However,dietary alfalfa powder increased water loss rates in pectoral muscle and leg muscle,and 30% alfalfa powder reduced the full-eviscerated carcass ratio of geese.The appropriate supplementation level of alfalfa powder was recommended at 10% in the present study.     

利木赞牛杂交改良对草原红牛肉质的影响

将纯种草原红牛和含1/2利木赞血缘的改良草原红牛各16头在相同营养水平和饲养条件下进行10个月的集中舍饲育肥，研究了2组牛生长速度、产肉率及眼肌面积、大理石花纹和嫩度等肉质水平。结果显示, 改良牛的体高、体长、胸围、体质量、增重、屠宰率和净肉率等极显著或显著地高于草原红牛（P<0.01或P<0.05），改良牛的眼肌面积比草原红牛增8.39%，大理石花纹等级和嫩度剪切力值也略大于草原红牛，但差异均不显著(P>0.05)。试验结果表明，利木赞牛对草原红牛的肉用性能改良效果显著，且对草原红牛的肉质没有明显影响,草原红牛保持了其原有肉质好的品种特性。     

魔芋粉饲喂肉鸭的价值探讨

试验用含魔芋粉0%、2%、3%、4%的饲粮饲喂12日龄的樱桃谷杂交肉鸭SM3,探讨魔芋粉作为一种饲料原料的饲用价值。结果表明:用含魔芋粉的日粮饲喂肉鸭,对肉鸭的日增重、耗料量和增重饲料成本没有明显影响(P>0.05),但对鸭的总增重和经济效益有一定影响。在本试验中,添加2%的魔芋粉使肉鸭的总增重增加,经济效益最好。     

白耳黄鸡生产性能和肉质性状的研究

对白耳黄鸡生长性能、屠宰性能、常规肉质、胸腿肌化学成分、肌肉组织学特性、胸肌氨基酸和脂肪酸含量等指标进行了研究。白耳黄鸡公母鸡的屠宰率、胸肌率、腿肌率、蛋白质含量、氨基酸总量、腹脂率、人体必需氨基酸含量、必需脂肪酸含量等分别为89.23/90.18%,16.65/18.09%,22.37/21.91%,23.64/25.30%,206.29/218.8mg/g,1.64/2.39%,92.78/96.75mg/g,30.69/29.52%。结果表明,白耳黄鸡的各指标都表现优良,其具有屠宰性能好,肉质优良,必需氨基酸和脂肪酸含量高,腹脂率低等特点,是一个值得推广的地方优良品种。     

萧山草三黄鸡屠宰性能和肉质分析

研究对70日龄萧山草三黄鸡进行了屠宰性能和肉质性状的测定,结果显示:公鸡活重、屠体重、半净膛率和全净膛率优于母鸡,差异显著(P<0.05)。腿肌的肉色OD值、剪切力和pH值均大于胸肌,系水力小于胸肌,差异均显著(P<0.05);水分含量、粗脂肪含量大于胸肌,粗蛋白含量、粗灰分含量小于胸肌,差异均显著(P<0.05)。研究表明母鸡的肉质优于公鸡,屠宰性能则不及公鸡。