新疆褐牛犊牛在天然草场放牧条件下生长发育的研究

[目的]选用2～4月龄的新疆褐牛牛犊,研究其在放牧条件下体重、体尺的变化情况,为更好地指导新疆褐牛犊牛在放牧条件下的生产.[方法]通过在夏牧场进行现场试验,测定新疆褐牛犊牛的体尺指标和体重.[结果]从2.5到4.5月龄增重55.78 kg,日增重达0.930 kg.4.5月龄胸围比2.5月龄增加20.78%.3.5月龄的体斜长比2.5月龄增加10.2 cm,增幅为11.12%;4.5月龄比3.5月龄增长5.3 cm,增幅为5.20%,比2.5月龄增长15.5 cm,增幅为16.90%.4.5月龄体高比2.5月龄长高了11.7 cm,长高幅度为13.48%.4.5月龄管围比2.5月龄管围增大1.3 cm,增大幅度为10.66%.[结论]随着月龄的增加,体重增长迅速,体尺指标也在增长,尤其相差一个月以上差异明显,但增幅呈下降趋势.     

后备母猪不同月龄配种与繁殖成绩的关系

以广东华农温氏畜牧股份有限公司下属鹤山分公司宅梧种猪场和更楼种猪场2013年1月1日至12月31日长大二元母猪分娩数据为基础,探讨后备母猪第1次配种的适宜月龄。从1胎繁殖成绩来看,7.5~8.5月龄初配,母猪窝产仔数、窝产健仔数和配种分娩率较好且稳定,过早和过晚配种都不利于提高1胎母猪的繁殖成绩;从2胎和3胎的繁殖成绩来看,7~7.5月龄初配的母猪窝产健仔数相对较低,9.5月龄以上初配的母猪配种分娩率相对较低;从4胎的繁殖成绩看,7~7.5月龄和10~10.5月龄初配的母猪窝产仔数、窝产健仔数、配种分娩率相对较低。说明后备母猪一般7.5~9月龄初配生产成绩较稳定,经济效益较高。     

家兔繁殖特点及提高繁殖力的措施

家兔的性成熟时间因品种、性别、个体、营养水平和出生季节等因素不同而有差异。小型品种的性成熟为3-4月龄,初配年龄为4~5月龄;中型品种的性成熟为4.5~5.5月龄,初配年龄为5~6月龄;大型品种的性成熟为6-7月龄,初配年龄为7-8月龄。肉用品种比毛用品种早1～1．5个月;     

不同年龄西门塔尔牛日粮中增饲补充料对生产性能的影响

11～ 4 4日龄、90～ 115日龄、1～ 5月龄和 11～ 15月龄的西门塔尔牛 ,在饲喂秸秆、杂草、少量土豆和玉米面等传统饲料的基础上 ,补充犊牛补充料 10 0g和 2 0 0 g ,肉牛补充料 5 0 0 g,改善了日粮中蛋白质、钙、磷和微量元素的状况 ,日增重显著提高了 2 5 2 1%、4 5 4 1%、4 7 32 %和 4 9 91%。     

PRRS疫苗免疫策略研究进展:疫苗程序改变为弱毒苗和灭活苗组合使用能增加免疫效果

<正>1实验室研究本研究对猪I型PRRS活疫苗(MLV)免疫接种和MLV与灭活疫苗(KV)的组合免疫接种的免疫应答进行了比较。实验设计如下(如表1),将32头小猪随机分成4组,每组8头。A组、B组、C组各组猪于1.5月龄时注射I型PRRS弱毒疫苗,D组为不注射疫苗的对照组。在猪4.5月龄时,A组注射第2次I型PRRS弱毒疫苗,B组和C组注射I型PRRS灭活疫苗(PROGRESSIS,法国Marial公司生产,2 mL,肌肉注射)。在猪5.5月龄时,C组再注     

獭兔毛囊分化与被毛生长规律研究

通过对1～7月龄四川白獭兔进行皮肤取样、切片和sacpic染色分析,显微镜毛囊图像成像,观察獭兔不同月龄毛囊分化与被毛生长变化规律。观测结果表明,獭兔1～2月龄时,毛囊处于分化增生期;3月龄、5月龄、7月龄毛囊处于分化全休止期;3～4月龄、4～5月龄时,毛囊处于休止与分化增生分化交替期;而在4月龄獭兔被毛密度达到21 075根/cm2,被毛密度极显著高于其他月龄(P<0.01),4月龄后被毛长与被毛密度逐渐趋于稳定。因此3～4月龄或4～5月龄为獭兔毛囊分化与被毛生长期。     

HSP27和HSP90在猫不同发育时期子宫的表达规律研究

为了探讨热休克蛋白(HSP) 27和HSP90在不同发育时期猫子宫中的表达情况,试验采用免疫组织化学技术分别检测HSP27和HSP90蛋白在5月龄、10月龄、1岁龄、1. 5岁龄、1. 5岁龄(妊娠20 d)猫子宫中的分布与表达情况。结果表明:HSP27在5月龄和10月龄猫子宫中不表达,在1岁龄、1. 5岁龄和1. 5岁龄(妊娠20 d)猫子宫中表达,不同强度阳性区域出现在腔上皮、腺上皮、固有层、血管内皮和子宫肌层中,妊娠期尿囊绒毛膜弱表达; HSP90在10月龄、1岁龄和1. 5岁龄子宫中未见表达,在5月龄和1. 5岁龄(妊娠20 d)猫子宫中表达,5月龄猫子宫腔上皮和腺上皮呈弱表达,1. 5岁龄(妊娠20 d)猫子宫腔上皮呈强表达,浅层腺上皮中等表达,深层腺上皮和尿囊绒毛膜弱表达,在子宫固有层、肌层和血管内皮未见表达。说明HSP27和HSP90蛋白在猫不同发育时期子宫中的表达具有差异性,提示两种热休克蛋白参与子宫重塑过程中子宫细胞凋亡和细胞增殖等过程。     

初配时间对母兔繁殖性能、体况及后代生长发育的影响

为研究不同初配时间对母兔繁殖性能、体况及其后代生长发育的影响,本试验选用同期出生的120只4月龄新培育肉兔配套系终端母本,按初配年龄分为4组,分别在4.5月龄、5月龄、5.5月龄和6月龄进行初配。结果表明,不同年龄初配时的发情率差异显著(P0.05)、初配年龄显著影响母兔第一胎配怀率(P0.05)、泌乳力差异极显著(P0.01)、初配体重(P0.01)、产后体况(P0.01)以及仔兔生长发育(P0.01),而对产仔率、胎产仔数、产活仔数、初生窝重、断奶成活率的影响不显著(P0.05),其中6月龄初配母兔综合生产性能最好,其次为5.5月龄初配母兔,二者间差异不显著,由于后者饲养成本更低,因此该母本的适宜初配时间为5.5月龄。     

Oct4在不同时期牛睾丸组织中的表达

为探明不同时期牛睾丸组织中干细胞的表达特点,以2.5月龄、4月龄牛胎儿和出生后1年牛、2年牛睾丸为试验材料,通过HE染色和免疫组化法染色,探讨了不同时期牛睾丸的组织学特征及Oct4在睾丸组织中的表达。结果显示,早期胎儿阶段的牛睾丸组织细胞呈现团状,睾丸组织中细胞随着年龄增长逐步分化形成管状,在2.5月龄和4月龄胎牛睾丸组织中,Oct4阳性细胞广泛分布于睾丸组织生精小管细胞团和睾丸间质中;在出生后1年牛睾丸组织中,阳性细胞主要分布于牛睾丸组织生精小管基底膜,在睾丸间质中数量较少或没有;在出生后2年牛睾丸组织中,仅在睾丸组织生精小管基底膜的少量细胞呈现Oct4阳性。试验证实了随着牛年龄的增长,牛睾丸组织中Oct4阳性细胞逐渐减少或消失。     

狼的笼养繁殖

1 生物学及繁殖特性 狼(Canis lupus)属食肉目、犬科、犬属,体长约1～1.6m,体重30～40 kg.栖息于山地、平原、荒漠等地带.狼的体成熟年龄为32月龄,在东北地区产仔季节为4～5月份,12月龄达性成熟.     

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.     

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.     

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.     

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