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81.
将36 头盘江黄牛及其杂交牛分成12 组,采用不同的日粮,进行两期育肥试验,得到不同的增重水平和实际营养物质摄入量。用各组实际采食的干物质( DM) 、粗蛋白(CP) 、综合净能(NEmf) 与我国试行的《肉牛饲养标准》进行比较。结果表明,除干物质与标准相差较多( - 6 .3 % ) 外,粗蛋白和综合净能与标准相当接近( 仅相差- 1 .5 % 和2 .8 % ) ,说明盘江黄牛及其杂交牛在育肥中的营养需要基本与标准相符,在配制日粮时,可以参考我国的《肉牛饲养标准》。 相似文献
82.
The kinetics of the production of interferon gamma (IFN-) in whole blood culture and its comparison with anti-listeriolysin O (ALLO) detection by ELISA were studied during oral infection of calves with Listeria monocytogenes. Culture filtrate antigen (CFA), listeriolysin O (LLO), and sonicated antigen (SA) were used to prime the peripheral blood mononuclear cells (PBMCs) and the plasma from orally infected calves. IFN- and ALLO appeared as early as day 7 of an oral infection. IFN- was detected earlier with LLO than with SA. The Max50 interleukin (IL-2) activity and IFN- estimated in the culture supernatant from PBMCs primed in vitro with different antigens of L. monocytogenes revealed high induction of IL-2 and IFN- by CFA, LLO and live antigen. IFN- assay and ALLO detection were used for testing cases of repeat breeding in dairy cattle. It appeared that detection of IFN- employing LLO can be used to diagnose listerial infections. 相似文献
83.
84.
T.M. Brown-Brandl J.A. Nienaber R.A. Eigenberg T.L. Mader J.L. Morrow J.W. Dailey 《Livestock Science》2006,105(1-3):19-26
Heat stress in cattle causes decreases in feed intake and feed efficiency; in extreme cases, it can cause death. These losses amount to millions of dollars each year. A study was designed to determine severity of heat stress among four breeds of cattle. Throughout two summers, 256 feedlot heifers of four different breeds were observed. Respiration rates, panting scores, and surface temperatures were taken twice each day on 10 animals/breed for several weeks during the summers of 2002 and 2003. Twenty-four-hour behavior measurements were recorded for four heat-stress and four thermoneutral days. Results showed during the afternoon, Angus cattle (black) had the highest respiration rates, panting scores, and surface temperatures, followed by the MARC III (dark red), Gelbvieh (tan), and Charolais (white). Behavior data showed that heat stress increased drinking and standing behavior, and decreased eating, lying, and agonistic behaviors, and that dark-hided cattle adjusted their behavior more than light-hided cattle. Overall, it was found that breed of cattle with dark-hides were more affected by temperature changes and at peak temperatures than breeds of cattle with light-hides. 相似文献
85.
Wurzinger M Ndumu D Baumung R Drucker A Okeyo AM Semambo DK Byamungu N Sölkner J 《Tropical animal health and production》2006,38(7-8):571-581
A survey in Burundi, Rwanda, Tanzania and Uganda was conducted in order to determine the different production systems under
which Ankole cattle are currently kept. Additionally, selection criteria of livestock keepers were documented. In Burundi,
Rwanda and parts of Uganda, livestock keepers are sedentary and herds are small, whereas in the other areas Ankole cattle
are kept in large herds, some of them still under a (semi-)nomadic system. Milk is the main product in all areas, and is partly
for home consumption and partly for sale. Although the production systems vary in many aspects, the selection criteria for
cows are similar. Productive traits such as milk yield, fertility and body size were ranked highly. For bulls, the trait ‘growth’
was ranked highly in all study areas. Phenotypic features (coat colour, horn shape and size) and ancestral information are
more important in bulls than in cows. The only adaptive trait mentioned by livestock keepers was disease resistance. In areas
of land scarcity (Burundi, Rwanda, western Uganda), a clear trend from pure Ankole cattle towards cross-bred animals can be
observed. 相似文献
86.
Brun-Hansen HC Kampen AH Lund A 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2006,35(2):182-187
BACKGROUND: Age-related changes in hematologic values are known to occur in many species. Few published studies include repeated measurements of hematologic parameters in calves during the first months of life. OBJECTIVE: The aim of the present study was to monitor hematologic values by sequential measurements from birth to 6 months of age in 15 healthy calves of the Norwegian Red breed, and compare the results to reference intervals for adult, lactating dairy cows. METHODS: Fifteen clinically healthy calves were sampled every week during the first 5 weeks of life and every month thereafter until 6 months of age. Hematologic values were measured using the ADVIA 120 hematology system. Reference intervals were determined for 75 healthy adult cows of the same breed. RESULTS: Compared with adult reference intervals, the MCV was lower and the RBC count was higher in calves throughout the investigation period. Hemoglobin concentration stayed largely within the adult reference interval. Mean MCHC was lower than adult values for 5 weeks, then increased and reached adult values by weeks 10-12. The mean lymphocyte count for calves reached adult reference values at weeks 6-8, and the mean monocyte count increased steadily until weeks 14-16. For most leukocytes, interindividual variation was larger during the first 5-8 weeks of life. The mean platelet count for calves was higher than the adult reference interval until weeks 19-21 of age. CONCLUSIONS: Age-specific reference intervals for calves from birth to 6 month of age are needed for RBC count, MCV, MCHC, red cell distribution width, and platelet and lymphocyte counts. 相似文献
87.
88.
本研究选用草原红牛、草原红牛与利木赞牛杂交后代共计42头作为试验牛群体,以体尺、体重作为衡量其生长发育指标,进行肉牛肌肉度线性评分,并屠宰测定其肉用性能,利用SPSS软件分析了3个微卫星位点基因标记与生长性状、屠宰肉用、肌肉度线性评分性状的关系。结果表明,IDVGA46等位基因D(211bp)对3个肌肉度评分性状肩部、腰厚、大腿肌有负相关;等位基因B(205bp)在腰厚方面有正相关。等位基因F(249bp)对牛的胸深、坐骨端高等生长性状有正相关。BM1824等位基因C(211bp)对腿围性状、净肉率和净肉重性状均有正相关。IDVGA2等位基因C(209bp)对牛的肉用性能有负相关。 相似文献
89.
90.
Itaru Sato Jun Sasaki Hiroshi Satoh Masahiro Natsuhori Takahisa Murata Keiji Okada 《Animal Science Journal》2019,90(8):1090-1095
Blood and urine were compared to clarify which is a better sample for estimating the concentration of radioactive cesium in muscles of live cattle. The most probable concentration of 137Cs in muscles was 21.0 times that in blood, and the error of this estimation was 28%. The concentration of 137Cs in blood was estimated accurately using urine samples. The estimation error did not increase so much (33%), even when the concentration of 137Cs in muscles was estimated using urine samples. On the other hand, the maximum volume of blood that can be collected with one syringe is 50 ml, whereas it is easy to collect 1,000 ml of urine. It took at least 360 min to confirm that a cow meets the legal standard by inspecting 50 ml of blood. However, with 1,000 ml of urine, a 20 min measurement time was sufficient for this purpose. This difference in the required measurement time is critically important for practical use. In addition, urine can be collected by farmers themselves, whereas the blood collection requires a veterinarian. Therefore, urine is a more convenient and practical sample for estimating the contamination level of live cattle with radioactive cesium. 相似文献