日粮组成和能量水平对乌金猪肉品质的影响

本文旨在研究不同日粮组成和能量水平对乌金猪肉品质的影响,确定最优肉品质所需的日粮适宜能量水平.选取体重(15.18±0.85)kg的乌金猪90头,公、母各占1/2,随机分为5组,每组18头,下设3个重复,每个重复6头.试验采用单因子随机分组设计,以中国肉脂型生长肥育猪饲养标准能量需要设计中能量水平(组Ⅲ,消化能12.98 MJ/kg),以NRC(1998)生长肥育猪饲养标准能量需要设计最高能量水平(组Ⅰ,消化能14.22 MJ/kg),此两个能量水平间设计中高能量水平(组Ⅱ,消化能13.60 MJ/kg),在中能量水平下依次分别设计中低能量水平(组Ⅳ,消化能12.36 MJ/kg)和最低能量水平(组Ⅴ,消化能11.74 MJ/kg),每个能量水平间的梯度为0.62 MJ/kg.各组在不同生长阶段日粮蛋白质、微量元素、氨基酸等水平基本固定.试验期至100 kg体重,分别在30、60和100 kg体重时屠宰,测定肉品质指标及肌肉营养成分,采用模糊综合评定系统分析并确定最优肉品质日粮适宜能量水平.结果表明,不同日粮组成和能量水平对乌金猪不同生长阶段肌肉pH、系水力、剪切力、烹煮损失和滴水损失有明显影响,组Ⅰ、Ⅲ、Ⅴ及其日粮的组间差异显著(P<0.05),大理石纹在60和100 kg体重时差异显著(P<0.05).随着日粮能量水平的降低,肌肉中粗蛋白质含量提高,在100 kg体重时达显著水平(P<0.05);粗脂肪、肌内脂肪和肌苷酸含量降低,不同生长阶段组Ⅰ、Ⅲ、Ⅴ及其日粮的组间差异显著或极显著(P<0.05或P<0.01).以大理石纹、剪切力、滴水损失为评定肉品质的代表指标,通过综合评定确定30、60和100 kg体重时最优肉品质适宜的日粮能量水平分别为13.10、13.08和13.11 MJ/kg.研究结果可为乌金猪的合理饲养和改善肉品质提供科学依据.     

不同日粮能量水平对肉仔鸡生产性能和屠宰性能的影响

为了研究不同能量水平日粮对21～45日龄艾维茵肉仔鸡生产性能和屠宰性能的影响,试验选择21日龄150只艾维茵肉鸡,随机分成3组,每组5个重复,每个重复10只鸡,在相同蛋白质水平下(19.50%),试验Ⅰ组、Ⅱ组和Ⅲ组肉仔鸡分别用12.50 MJ/kg、12.90 MJ/kg和13.30 MJ/kg的能量水平日粮饲喂,预试期为3 d,正试期为21 d,检测日增重、日采食量、料重比、胴体重、腹脂率、全净膛率、胸肌率以及腿肌率。结果表明:试验Ⅱ组和试验Ⅲ组的平均日增重、日采食量均显著高于试验Ⅰ组(P0.05),试验Ⅱ组和试验Ⅲ组间平均日增重、日采食量均差异不显著(P0.05),各组间料重比差异显著(P0.05);试验Ⅱ组和试验Ⅲ组的胴体重、腹脂率显著高于试验Ⅰ组(P0.05),试验Ⅱ组和试验Ⅲ组间胴体重、腹脂率差异不显著(P0.05),各组间全净膛率、胸肌率、腿肌率均差异不显著(P0.05)。说明日粮能量水平为12.90 MJ/kg时,肉鸡的生产性能和胴体性能表现较好。     

饲粮能量、蛋白质水平对生长猪生产性能的影响

采用2×2因子设计,能量和蛋白质各设2个水平,分别在NRC推荐水平上提高或降低10%,以考察饲料能量、蛋白质水平对生长猪生产性能的影响.试验以NRC水平为对照,共5个处理,每个处理4个重复,每个重复4头猪.将80头生长猪随机分为5个处理.试验结果:与对照组相比,高能高蛋白组(15.6MJ/kg,18.7%)日增重显著降低(P<0.05),其他处理组差异都不显著(P>0.05);低能低蛋白组(12.78MJ/kg,15.3%)日增重显著低于其他两个处理组;高能和高蛋白均显著降低采食量,料肉比有所降低,但差异不显著.结果表明适宜能量和蛋白质水平为NRC水平.     

日粮能量蛋白质水平对荣昌烤乳猪品系生E性能和肉质性状的影响

本研究旨在探讨日粮中不同能量和蛋白质水平对荣昌烤乳猪品系生长性能和肉质性状的影响,建立荣昌烤乳猪品系适宜营养水平.试验按照2×3因子设计,设2个能量水平(14.10和15.06 MJ/kg),3个蛋白质水平(16%、18%和20%).试验选用(24±2)日龄断奶、体重(5.01±0.73)kg的荣吕烤乳猪系健康仔猪120头,随机分为6个组,每个组4个重复,每个重复5头猪.试验期21 d.结果表明:(1)日粮能量水平显著影响仔猪日增重(P=0.006)和料肉比(P=0.030),高能水平下仔猪生长性能优于低能水平.日粮蛋白质水平显著影响仔猪日采食最、日增重和料肉比(P<0.05),蛋白质水平18%组生长性能优于16%和20%组.能量和蛋白质的交互作用除了对日增重影响差异显著(P=0.021)外,对其余生长性能指标影响不显著(P>0.05);(2)日粮能量水平极显著影响肌肉粗蛋白质含量和蒸煮损失(P<0.01),对肌肉总色素和肌纤维密度的影响显著(P<0.05).日粮蛋白质水平极显著影响肌肉粗蛋白质、肌内脂肪和蒸煮损失(P<0.01),对其余肉质性状指标影响不显著(P>0.05).能量和蛋白质的交互作用对肌肉粗蛋白质、肌纤维直径和肌纤维密度影响极显著(P<0.01),对肌肉总色素及蒸煮损失的影响显著(P<0.05).综上可知,日粮能量和蛋白质水平显著影响荣昌烤乳猪品系生长性能和肉质性状,5～11 kg荣昌烤乳猪品系适宜的消化能水平为15.06 MJ/kg,粗蛋白质水平为18%.     

不同蛋白质水平日粮对深县猪生长性能、养分消化率和血液生化指标的影响

为了研究不同蛋白质水平日粮对深县猪生长性能、养分消化率和血液生化指标的影响,试验选择体重(15.33±1.95)kg的健康深县猪64头,随机分成4组,每组4个重复,每个重复4头猪。对照组日粮蛋白质水平为16.88%,试验Ⅰ组、试验Ⅱ组、试验Ⅲ组日粮蛋白质水平分别为15.00%、16.00%、17.00%。结果表明:试验Ⅱ组的平均日增重显著高于对照组、试验Ⅰ组(P0.05);试验Ⅱ组的料重比显著低于对照组、试验Ⅰ组(P0.05);粗蛋白与粗脂肪表观消化率各试验组与对照组之间差异不显著(P0.05),试验Ⅱ组显著高于试验Ⅰ组(P0.05);总能表观消化率试验Ⅱ组显著高于对照组、试验Ⅰ组(P0.05);试验Ⅱ组、试验Ⅲ组血液白蛋白和总蛋白含量均显著高于对照组(P0.05)。综合各项指标,在本试验条件下,生长期深县猪日粮适宜的蛋白质水平为16.00%。     

日粮能量水平对八眉三元杂交猪生长性能、屠宰性能及肉质性状的影响

为了研究不同能量水平日粮对生长育肥期八眉三元猪生长性能、屠宰性能和肉质性状的影响,以确定其适宜的日粮能量水平试验设计3个试验组,即低能量组(G1, 11.70 MJ/kg)、中能量组(G2, 12.95 MJ/kg)和高能量组(G3, 14.23 MJ/kg),试验期为117 d。结果显示:随能量水平增加,猪的平均日增重显著上升(P0.05),料肉比显著下降(P0.05);体斜长及眼肌面积随能量水平增加而减小(P0.05),平均背膘厚增加(P0.05);能量水平的变化对脏器的生长无明显影响(P0.05),但对内脏脂肪的沉积有促进作用;各组肉色、大理石花纹评分、肌苷酸含量、pH_(45min)及熟肉率等指标均无明显差异(P0.05);肌肉的系水力随能量水平的增加而增加(P0.05)。试验结果表明,中能量水平日粮组能够获得与高能量日粮组相近的生长性能、屠宰性能及肉品质,是三元猪的最适能量选择。     

饲粮锌添加水平对猪生长性能和胴体品质的影响

试验旨在研究饲粮锌添加水平对猪生长性能、养分表观消化率和胴体品质的影响,选取80日龄杜长大商品猪90头,体重(34.31±2.11) kg,随机分为3组,每组6个重复,每个重复5头。试验Ⅰ组饲喂添加250 mg/kg锌的基础饲粮,试验Ⅱ组饲喂不添加微量元素锌的基础饲粮,试验Ⅲ组饲喂添加NRC推荐锌添加量(30～50 kg添加锌60 mg/kg,50～100 kg添加锌50 mg/kg)的基础饲粮,预试期5 d,试验期为76 d。结果表明:1)试验Ⅰ、Ⅲ组日增重高于试验Ⅱ组,分别增加7.49%和5.18%(P0.05),试验Ⅰ组日增重比Ⅲ组增加2.20%,但是各组间差异均不显著(P0.05)。各试验组间日采食量、料重比差异不显著(P0.05);2)试验Ⅰ、Ⅱ、Ⅲ组饲粮中粗蛋白质、钙、磷、酸性洗涤纤维、中性洗涤纤维和锌的表观消化率相近,组间差异不显著(P0.05)。试验Ⅰ组粪中锌的残留量极显著高于试验Ⅱ、Ⅲ组(P0.01),试验Ⅲ组显著高于试验Ⅱ组(P0.05);3)Ⅰ、Ⅱ、Ⅲ组间瘦肉率、背膘厚、肌肉颜色、pH1、滴水损失和嫩度差异不显著。综上分析,饲粮锌添加水平对猪的生长性能、养分表观消化率和胴体品质的影响不显著,但是饲粮锌添加水平显著影响粪中锌残留量。生猪饲粮锌添加以NRC(2012)推荐添加量为宜,无需额外添加。     

不同粗蛋白水平对乳鸽生长后期增重的影响

将300只14日龄乳鸽随机分为Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ五个组进行试验,分别饲喂代谢能恒定为12.94MJ/kg,粗蛋白为16%、18%、20%、22%、24%五个水平的日粮。结果表明:日粮中不同的粗蛋白水平对乳鸽增重和饲料转化率均有显著的影响。随着日粮蛋白质水平的提高,乳鸽增重呈上升的趋势。Ⅰ组乳鸽的日增重显著低于其它组(P<0.05或P<0.01),Ⅱ组低于Ⅲ组、Ⅳ组,差异显著(P<0.05),但Ⅱ组与Ⅴ组、Ⅲ组与Ⅳ组之间,差异不显著(P>0.05);Ⅰ组的饲料转化率低于其它组,差异显著(P<0.05),其它组之间差异不显著。     

日粮中能量对大河乌猪胴体品质的影响

试验选择血缘、胎次、体质量相近的大河乌猪40头,分成5组,每组8头,消化能水平依次为:1组11.05MJ/kg、2组11.63MJ/kg、3组12.26MJ/kg、4组12.89MJ/kg、5组13.47MJ/kg。分20~50kg和50~90kg2个饲养试验阶段,试验结束后,进行胴体性状及肉质测定。研究结果表明,日粮中能量对大河乌猪胴体性状和肉品质都有一定的影响,但是各指标组间差异均不显著,同时试验结果证明,大河乌猪这种国家级地方猪种不适宜用高能量日粮饲养(高能≠高效),相反用低能量(11.05MJ/kg)日粮饲养,可能会取得较佳的胴体品质和经济效益。     

日粮能量水平对育成期崂山奶山羊屠宰性能的研究

试验旨在研究日粮能量水平对育成期崂山奶山羊屠宰性能的影响。选择体重相近(17.43±0.76)kg的崂山奶山羊育成母羊30只,采用单因素设计,随机分成3个处理,每处理10个重复,每重复1只羊。分别饲喂粗蛋白质、钙及磷水平基本一致,消化能(DE)水平依次为10.40 MJ/kg、11.47 MJ/kg及12.51 MJ/kg的3种TMR。结果表明:能量水平对试羊的胴体重有显著影响(P0.05);10.40 MJ/kg组试羊屠宰率显著低于12.51 MJ/kg组(P0.05),3组试羊的胴体净肉重、内脏脂肪及骨重呈极显著差异(P0.01);10.40 MJ/kg组与11.47及12.51 MJ/kg组试羊肉骨比呈显著差异(P0.05);3组试羊的胴体净肉率无显著差异(P0.05)。能量水平对3组试羊的内脏器官有显著影响(P0.05)。3组试羊的肝胆、肺脏、血液及头的重量差异极显著(P0.01);11.47 MJ/kg组试羊心脏重量极显著高于10.40及12.51 MJ/kg组(P0.01),10.40MJ/kg组试羊显著低于12.51 MJ/kg组(P0.05);10.40 MJ/kg组试羊脾脏及肾脏重量极显著低于11.47及12.51 MJ/kg组(P0.01);能量水平对3组试羊的胃肠道有显著差异(P0.05)。3组试羊的瘤胃、网胃及小肠重量呈极显著差异(P0.01)。适当提高饲粮能量水平,育成期崂山奶山羊生长速度明显加快,其宰前活体质量、胴体质量和屠宰率随能量的增加而增加。12.51 MJ/kg能量水平对崂山奶山羊肝脏、肺脏、肾脏、胃肠道、蹄及皮(毛)的生长发育具有较大促进作用。     

Phase I evaluation of CCNU (lomustine) in tumor-bearing cats

1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.     

Prevalence of gastric lesions in racing Alaskan sled dogs

Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.     

Furosemide continuous rate infusion in the horse: evaluation of enhanced efficacy and reduced side effects

Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.     

Internal Parasites and Haematological Values in Cattle Slaughtered in Buea Subdivision of Cameroon

Tropical Animal Health and Production -     

The Epidemiology of Gastrointestinal Nematodes of Dairy Cattle in Central Kenya

The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round.     

Diversity of Ectoparasites in Sheep Flocks in Sa~o Paulo,Brazil

The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host.     

Chemotaxis of macrophage in inflammation

Our particular attention in this article was given to natural mediators for macrophages isolated from the sites of tissue injury. A number of chemotactic factors, which may satisfy many criteria making them acceptable as inflammatory leucocyte chemotactic factors, has been separated. Among them, our laboratory has isolated three macrophage (monocyte) chemotactic factors (MCF-a, -b and -c). Their purification, characterization and functional specificity are discussed.     

Evaluation of biohydrogenation rate of canola vs. soya bean seeds as unsaturated fatty acids sources for ruminants in situ

An experiment was conducted to study disappearance of C14 to C18 fatty acids, lag times and biohydrogenation (BH) rates of C18 fatty acids of ground soya bean and canola seeds in situ. Three ruminally fistulated Dallagh sheep were used to determine ruminal BH of unsaturated fatty acids (UFAs). Differences in the disappearance of fatty acids through the bags and lag times were observed between the oilseeds. We saw that the longer the incubation time of the oilseeds in the rumen, the lower the content of C18:2 and C18:3. Significantly higher lag times for both C18:2 and C18:3 were observed in ground canola compared to ground soya bean. BH rates of C18:2 and C18:3 fatty acids in soya bean were three times higher than those of canola. These results suggest that the fatty acid profile of fat source can affect the BH of UFAs by rumen micro‐organisms. So that UFAs of canola had higher ability to escape from ruminal BH. It seems that fatty acid profile of ruminant products is more affected by canola seed compared to soya bean seed.     

Serum biochemical values and mineral element contents of tissues in yaks

Serum biochemical values and the wet weight to dry weight ratios of tissues were determined in yaks in Shandan county of Gansu province. The liver, kidney, heart and muscle contents of seven elements in yaks were also analysed. Most serum biochemical values were similar to those of cattle, camels and sheep, but the calcium concentration was considerably above the normal range for other ruminants. The liver contained the highest concentrations of copper, manganese and cobalt and the kidney of selenium, iron and calcium.Abbreviations Alb albumin - ALT alanine aminotransferase - AST aspartate aminotransferase - BUN blood urea nitrogen - Chol cholesterol - Glob globulin - -GT -glutamyl transpeptidase - IP inorganic phosphorus - TP total protein