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1.
为了研究皮埃蒙特牛改良南阳牛遗传育种研究进展,本文综述了皮埃蒙特牛杂交改良南阳牛的历史进程,皮埃蒙特牛改良南阳牛杂交后代繁殖性能研究,皮埃蒙特牛改良南阳牛杂交后代肉用性能研究,并提出了产业化集群开发的合理化建议。  相似文献   

2.
皮埃蒙特牛种性利用的研究   总被引:1,自引:0,他引:1  
本文就中意肉牛研究项目进展情况,从繁殖性能、育肥和屠宰性能及肉质性能方面阐述了皮埃蒙特牛的特性及与南阳牛杂交利用的育肥效果,并介绍了肉用牛线性体型评定的结果,分析了皮埃蒙特牛在国内的应用前景。  相似文献   

3.
“皮埃蒙特牛改良南阳牛技术推广”是农业部和国家外国专家局下达的项目,南阳市畜牧兽医工作站为项目承担单位。本项目通过引进国际上优秀的肉牛品种一皮埃蒙特牛的胚胎,采用胚胎移植技术,用南阳母牛作受体进行胚胎移植,繁育出纯种皮埃蒙特牛,然后利用人工授精技术,采用皮埃蒙特牛冻精改良南阳牛,提高南阳牛的产肉性能和经济效益。  相似文献   

4.
利用胚胎移植技术,快速扩繁皮埃蒙特牛,生产皮埃蒙特牛冻精与南阳牛杂交育种,开创了我国非活体引进培育皮南牛新品种的先河。本文对皮南牛生长发育、繁育性状、肥育性状、酮体性状、肉质性状等性能进行了系统研究。  相似文献   

5.
《中国牛业科学》1998,24(3):67-67
意大利皮埃蒙特牛意大利皮埃蒙特牛是世界上肉用性能最好的肉牛品种,品种选育时主要注意其早熟,包括提早达到屠宰体重时的月龄,对肉质和肌肉嫩度进行重点选育,不求大型体格,体重要求适中,成年母年体重500-600kg,育成公牛15-18月体重550-600k...  相似文献   

6.
为提高黄牛的生产性能,增加养殖效益,大通县从2001年引进并使用皮埃蒙特肉牛冻精对当地黄牛进行杂交改良。截止2002年10月冷配黄牛2926头,已产皮埃蒙特杂种牛2195头。结果显示皮埃蒙特杂交牛出生重29.47千克,比当地黄牛出生重22.42千克相对提高31.67%,6月龄、12月龄和18月龄体重分别为175.27千克、306.67千克和427.29千克,比当地黄牛相应月龄分别提高65.19%、84.22%和86.09%。因此,皮埃蒙特杂交牛的生产性能高于当地黄牛。  相似文献   

7.
南阳牛是我国五大良种黄牛品种之一,近些年国家越来越重视通过杂交改良的方法产生新品种培育工作,1986年引进了皮埃蒙特牛,与南阳牛进行杂交改良,通过30多年来的持续选育,横交固定形成了皮南牛新类群,它保持了南阳牛适应性好、耐粗饲的优点,同时继承了皮埃蒙特牛生长发育快、瘦肉率高的特点,但在皮南牛新品种培育过程中,仍存在核心...  相似文献   

8.
秦川牛是我国著名的役肉兼用地方黄牛良种,以体大力强、肉质鲜美、适应性强而著称于世。近年来随着农机化程度的不断提高,秦川牛应从生产资料向生活资料转移,要着重解决生长发育较慢、后躯发育欠充实的缺陷,提高优质肉产量。因此,必须通过导血改良,才能达到上述目的。周至县从1998年开始,用国外优良肉牛品种皮埃蒙特牛冷冻精液,对秦川牛进行杂交改良,累计改良黄牛2.15万头,杂交改良一代牛在体尺、体重及产肉性能方面与秦川牛进行对照,显示出良好的改良效果,  相似文献   

9.
引进皮埃蒙特牛胚胎,利用南阳牛作受体进行胚胎移植。不仅所生胚胎牛更适应当地环境条件,而且还节约外汇,减少疾病传播,充分发挥种公牛的遗传潜力。南阳牛作受体母牛体重在430~450kg,很少发生难产。皮埃蒙特牛种公牛年均采精次数72.1次,每次平均射精量5.11mL,一年四季均衡生产。同时,皮埃蒙特牛冻精的推广应用为皮南牛新品种培育提供优异的遗传材料。  相似文献   

10.
皮埃蒙特牛产于意大利的皮埃蒙特地区,是优质的肉用牛品种,具有屠宰率高,优质肉比率高,皮下脂肪少,瘦肉率高,肉质细嫩等特点,因而皮埃蒙特牛的育种工作也备受关注。一直以来,皮埃蒙特牛的育种组织工作由ANABORAPI协会统一管理,开展皮埃蒙特牛的良种登记,后裔测定,冻精生产及推广,后备种牛培育等工作。育种目标也集中在肉用早熟性和母牛产犊顺利方面。本文主要对皮埃蒙特牛的品种、育种组织和育种方案做出介绍。  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
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.  相似文献   

14.
15.
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.  相似文献   

16.
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.  相似文献   

17.
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.  相似文献   

18.
19.
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.  相似文献   

20.
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  相似文献   

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