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991.
Chronic fluoride toxicity in the form of osteo-dental fluorosis was observed in cattle, buffaloes, sheep and goats from 21 villages of Banswara, Dungarpur and Udaipur districts of Southern Rajasthan where the mean fluoride concentration in drinking water varied from 1.5 to 4.0 ppm. The prevalence of dental fluorosis in calves (<1 year age) was greater than that in adult cattle and buffaloes. At a fluoride concentration in the water of 4.0 ppm, 100% of calves, 65.6% of buffaloes and 61.0% of cattle were found to be affected with dental fluorosis to varying degrees. In the older group of buffaloes, their teeth were brownish black instead of creamy yellow as found in calves and cattle. Out of 780 goats and 564 sheep, none revealed evidence of osteo-dental fluorosis. The overall prevalence of skeletal fluorosis was 8.5%, with the highest prevalence of 29.0% in cattle and 37.5% in buffaloes at a fluoride concentration of 3.2 ppm. None of the calves were affected with skeletal fluorosis. Intermittent lameness was observed in the older group of animals (>7 years age) at 2.8 ppm fluoride or more in the water. None of the fluorotic animals exhibited any apparent evidence of hypothyroidism, stunted growth or low milk production. There was no correlation between gender and the prevalence of fluorosis, but the prevalence and severity of skeletal fluorosis increased with increasing fluoride concentration and age. Possible factors causing variation in fluorosis in the cattle and buffaloes in villages with identical fluoride concentrations are discussed.  相似文献   
992.
993.
A total of 376 chickens from different ecotypes were immunized with the non-pathogenic multi-determinant antigen sheep red blood cells (SRBC). The ecotypes included indigenous chickens from various locations in Tanzania (n=102), India (n=86) and Bolivia (n=89). In addition, eight German Dahlem Red (GDR) chicken lines with different major genes (dwarf, naked neck and frizzled) of tropical interest were also immunized with SRBC. Immune competence of the breeds was assessed by measuring complement haemolytic activity, both from the classical calcium-dependent complement pathway (CPW) and alternative calcium-independent complement pathway (APW), alongside IgTotal, IgG and IgM antibody responses to SRBC at 7 days post immunization. Large variations in complement activity and antibody responses to SRBC were observed within and between the indigenous breeds. Many indigenous chickens, especially from Bolivia, showed decreased complement activity (APW) following immunization with SRBC. Breeds from India showed the highest CPW activity and humoral (especially IgM) responses to SRBC, suggesting high immune competence. In contrast, Bolivian chickens were characterized by low CPW activity, low APW activity and low antibody levels to SRBC suggesting an overall low immune competence. In the GDR chickens, characterized by high CPW activity and high IgG antibody responses to SRBC, the major genes for naked neck, frizzling and dwarfism had no significant effect on the antibody responses and complement activity to SRBC.  相似文献   
994.
Pharmacokinetics of enrofloxacin in lactating sheep   总被引:4,自引:0,他引:4  
The pharmacokinetics of enrofloxacin (ENR) was investigated after its intravenous (iv) and intramuscular (im) administration in six healthy lactating sheep. After iv ENR injection (as a bolus), the elimination half-life (t(1/2beta)), the volume of distribution (Vd(area)), and the area under the concentration vs. time curve (AUC) were 3.30 (0.36)h, 2.91 (0.17)l/kg and 4.19 (0.18) microg h/ml, respectively. The maximum milk concentrations of ENR (C(max)), the area under the milk concentration vs. time curve (AUC(milk)) and the ratio AUC(milk)/AUC(serum) were 2.38 (0.14)microg/ml, 23.76 (2.21) microg h/ml and 5.62 (0.30), respectively. After im administration of ENR the t(1/2beta), C(max), time of C(max) (t(max)) and absolute bioavailability (F(abs)) were 3.87 (0.10)h, 0.74 (0.07) microg/ml, 0.83 (0.12)h and 75.35%, respectively. The C(max), AUC(milk) and the ratio AUC(milk)/AUC(serum) were 1.94 (0.13) microg/ml, 24.81 (2.25) microg h/ml and 8.15 (0.96), respectively.  相似文献   
995.
The prevalence and serotypic diversity of Mannheimia [Pasteurella] haemolytica and Pasteurella trehalosi from nasal swabs, sera and abattoir specimens from sheep in the highlands of Wollo, North East Ethiopia was investigated. Prevalence rates of 83% and 75% of these microorganisms were found in the serum samples and nasal swabs, respectively, from apparently healthy sheep. In a local abattoir, 205 lungs were investigated, 34% of which showed pneumonia, from which samples were collected from 51 lungs and the same number of corresponding tonsils. Mannheimia and Pasteurella species were isolated from 59% of these pneumonic lungs and 69% of the respective tonsils. M. haemolytica serotypes accounted for 41 (59%) and P. trehalosi for 11 (32%) of the isolates from the abattoir specimens. The majority (67%) of isolates from nasal swabs were P. trehalosi, M. haemolytica being isolated f rom 4 (13%) of the swabs. M. glucosida was isolated only from the tonsils. The predominant serotypes of the isolates from both the nasal swabs and the abattoir specimens were M. haemolytica A1 (17%) and P. trehalosi T4 (16%) and T3 (13%). P. trehalosi T15 was less commonly encountered, while M. haemolytica A9 and A13 were not isolated. Studies on sera from 100 sheep indicated that antibodies against M. haemolytica serotype A1 (14%) were most common, followed by A5 and A8 (each 10%) and A9 and P. trehalosi T3 (each 9%) and T4 (8%). Antibodies against M. glucosida or serotype A11 occurred in 2% of the sera. Multiple serotypes were common in all types of samples. The importance of including in vaccines the most prevalent serotypes involved in the pneumonia of sheep in the area is discussed.  相似文献   
996.
利用氨-碱-盐化和微生物技术复合处理作物秸秆,再配合工业副产品、精料及矿物质、维生素添加剂等制成颗粒饲料,饲喂成年滩羊,观察育肥效果。试验结果表明:试验组(复合处理秸秆)与对照组(未处理秸秆)相比,日增重提高25.06%,饲料报酬提高25.23%,屠宰率提高5.11%,净肉率提高7.71%,试验期内平均每只育肥羊多获利润13.13元。  相似文献   
997.
A retrospective case-control study was conducted on 6718 sheep of two breeds (2772 Horro and 3946 Menz) on risk factors for mortality associated with respiratory disease (MARD) in Ethiopia, based on data collected between October 1993 and December 1997. Potential risk factors examined were breed, gender, age, month, and air temperatures.Fifty-four per cent of total deaths in the flock could be attributed to respiratory disease and the annual MARD rate ranged between 6.3 and 19.0%. There was significant breed (P<0.0001) and gender (P<0.0001) difference in MARD. The Horro breed had a higher (P<0.0001) annual MARD than the Menz breed (16.5+/-0.18 vs. 12.4+/-0.15%). A higher (P<0.0001) proportion of males suffered than females (15.1+/-0.23% vs. 13.8+/-0.13%). Age was also an important risk factor for MARD: there was a strong polynomial relationship (R(2)=0.91, P<0.0001) between MARD and age; the risk of being young if a sheep was a MARD case was high. MARD was high between October and March but relatively low between the months of April and September. There was a significant (P<0.05) negative cubic relationship (R(2)=0.49) between monthly MARD and monthly average minimum air temperatures. There was also a significant (P<0.01) positive exponential relationship (R(2)=0.61) between monthly MARD and average monthly daily deviation between maximum and minimum air temperatures.Timely health and management interventions focusing on these factors are necessary to alleviate losses from MARD. Understanding variations in MARD risk within a population can enhance early response to potential outbreaks, reducing losses.  相似文献   
998.
Inverdale基因 (FecXI)是位于X染色体上影响绵羊排卵数的一个主效基因。本文简要介绍了FecXI 基因的发现、来源、内分泌学、产业化利用以及Inverdale母羊的卵巢特性 ,并对FecXI 基因的前景进行了讨论。  相似文献   
999.
对正在培育的中国美利奴多胎肉用细毛羊的羊毛品质做了综合分析.在毛丛自然长度方面,断奶公羔为4.37cm,母羔为4.43cm,周岁公羊为12.60cm,周岁母羊为11.47cm;羊毛的伸直长度周岁公羊为15.01cm.周岁母羊为14.86cm;羊毛纤维直径周岁公羊为21.67μm.周岁母羊为20.36μm;羊毛密度周岁公羊为5212根/cm^2.周岁母羊为5430根/cm^2.比2002年中国美利奴羊周岁羊相比还有较大差距;羊毛净毛率周岁公羊为64.60%.周岁母羊为65.64%。由上可知.除羊毛密度外.中国美利奴多胎肉用细毛羊总体上符合品种培育的要求.在今后的选育中要注意羊毛密度的提高。  相似文献   
1000.
在放牧条件下 ,用青海省江河源饲料发展有限公司生产的 3 0 3育肥羊颗粒饲料对 4~ 5月龄青海半细毛羔羊进行放牧加补饲育肥试验 ,每只羊补饲 0 .3 4kg d。育肥期 90d。试验组羊只均活重为 3 4.63± 5 .17kg ,比对照组提高7.90kg ,P <0 .0 1,差异极显著 ,7~ 8月龄羔羊达到出栏标准 ,经济和社会效益显著。  相似文献   
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