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211.
A survey on coccidial infections in goats from central Spain was carried out. Fifty-five goat farms from 28 localities belonging to the three bioclimatic subregions of the area were visited. Individual samples (702) were obtained from the rectum of 130 young (under 1 year of age) and adult (572 over 1 year of age) goats. Coproscopical analyses showed a 100% prevalence and a moderate average intensity (7606.48 +/- 17918.78 Eimeria oocysts per gram of faeces), although wide variations were seen among herds and among individuals within each goat flock. Statistical analysis showed a strong age-related reduction in oocysts output in goats up to 4 years of age. The intensity of coccidial infections (young and adult goats, herds) was independent of the prevailing bioclimatic conditions. Heavier infections in young goats were found in bigger herds, whereas adult goats from these same big flocks (over 300 animals) showed the lowest oocyst output. Under our conditions, neither the female restocking rate nor the age structure seemed to play a significant role in the intensity of the Eimeria infections.  相似文献   
212.
Six horses with chronic obstructive pulmonary disease (COPD) and 8 horses with recurrent urticaria were skin tested with 67 extracts from 58 allergens, including pollens, epidermals, cultivated farm plants, dusts, molds, and insects. Reactions were evaluated 3 times over a 24-hour period immediately after the injections. Results were compared with those obtained from 11 clinically normal horses. All horses had positive skin test reactions. Significant differences was evident between horses with COPD and clinically normal horses for only 3.0% of the possible extract reactions, and between horses with urticaria and clinically normal horses for only 4.5% of the possible extract reactions. Horses with COPD or urticaria had greater total percentage of allergen extract reactions than did clinically normal horses. Positive reactions were observed at all 3 evaluation periods, and late-onset reactions were not always preceded by positive reaction at earlier periods. All horses with COPD or urticaria had at least 1 skin test reaction that exceeded the mean +/- 2 SD, as calculated for each of the 67 extracts for the group of clinically normal horses.  相似文献   
213.
Pharmacokinetic parameters for the beta 2-adrenergic agonist, cimaterol (CIM), were determined in growing Holstein steers. Compartmental analysis was used after measurement of CIM in body fluids by affinity chromatography and HPLC using UV detection. Recoveries from spiked plasma and urine standards were 70 +/- 1.2% and 68 +/- 1.1%, respectively. The minimum detection level in plasma was 1 ng/mL and the average CV was 5.1% for concentrations that ranged from 1 to 30 ng/mL. Four steers (276 +/- 24 kg) received 15 mg of CIM by bolus intravenous injection. Plasma CIM levels declined in a biphasic manner with half-lives of 2.5 min for the distribution phase and 54 min for the elimination phase. A two-compartment open model was used to describe the disappearance of CIM and the following pharmacokinetic parameters were obtained: central compartment volume (Vc) = .76 L/kg, apparent volume of distribution (Vd) = 4.1 L/kg, and transfer rate constants from the central to peripheral compartment (k12) = .177/min, from the peripheral to central compartment (k21) = .054/min and elimination from the central compartment (kel) = .074/min. After 8 h, total urinary CIM accounted for only 18.3% of the administered dose. Results suggest that circulating concentrations of CIM in growing steers are influenced by its accumulation in an unidentified peripheral pool and its conversion into unknown metabolite(s) before elimination.  相似文献   
214.
The conventional culture method was compared to coagglutination for detection of Actinobacillus (Haemophilus) pleuropneumoniae in 425 sets of pig lungs. Sera from the same animals were evaluated for antibodies to A. pleuropneumoniae by the complement fixation (CF) test. All samples were collected at 2 packing plants in Iowa. In 2 nonvaccinated herds with no history of respiratory disease, the difference between standard culture results and coagglutination was highly significant (P less than 0.001). None of the 57 pigs in this group were positive for A. pleuropneumoniae by conventional culture, but 7 were positive by the coagglutination test. There were 15 animals with CF titers between 1:8 and 1:32. Animals from 6 herds vaccinated for A. pleuropneumoniae and without recent respiratory problems were evaluated. One out of 118 animals tested was positive for A. pleuropneumoniae by standard culture as compared to 9 positive by coagglutination. The difference in positive results between culture and coagglutination was highly significant (P less than 0.001). Twenty-eight animals had CF titers to A. pleuropneumoniae (1:4 to greater than or equal to 1:128). Two hundred fifty lungs and sera samples were collected from 7 herds which had recently experienced varying degrees of respiratory disease. Thirty-nine lungs were positive for A. pleuropneumoniae by culture and 182 were positive by coagglutination. The number of positives detected by coagglutination was significantly different (P less than 0.001) from the number positive by culture. There were 172 animals with antibody titers ranging from suspect to greater than or equal to 1:128. There were significantly fewer positive animals detected by standard culture than with the CF test (P less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
215.
选用6只9周龄新西兰母兔,评定环境温度和饲粮营养浓度对生长期母兔代谢能利用率的影响。试验在密闭式的小动物呼吸测热柜中进行。分别对处于环境温度为20±2℃和30±2℃,采食两种不同营养浓度的试兔进行测试。饲粮营养水平实测值,分别为12.22kJ ME/g和13.49kJ ME/g;粗蛋白质(CP)分别为17.3%和21.6%;中性洗涤纤维(NDF)分别为23.7%和16.5%。结果表明:环境温度影响试兔的能量平衡,它与采食量间存在着显著的相关。20±2℃时,相关系数r=0.798;30±2℃时,相关系数r=0.875。在本试验设计范围内,饲粮营养浓度并不影响代谢能食入量(ME_I),热增耗(HP)和能量平衡(EB)。当环境温度为20±2℃和30±2℃时,表观代谢能转化率(NE/ME)分别为51%和71%;每天每兔每千克代谢体重代谢能维持需要分别为396 kJ和361 kJ。试验结果认为:环境温度影响营养物质消化率(P相似文献   
216.
The release of tumor necrosis factor-alpha (TNF-) from cultured bovine alveolar macrophages (BAM) was evaluated following stimulation of BAM with bovine herpesvirus-1 (BHV-1), parainfluenza-3 (PI-3) virus, bovine respiratory syncytial virus (BRSV), Escherichia coli 0111:B4 endotoxin, Pasteurella haemolytica type 1 endotoxin, Pasteurella multocida endotoxin, and virus/endotoxin combinations. A cytotoxic assay system using Georgia bovine kidney cells as targets was used to measure TNF- activity. The cytotoxic activity was neutralized by an anti-human TNF- monoclonal antibody.

Stimulation of BAM with 1 median tissue culture infectious dose (TCID50) of live or ultraviolet (UV)-inactivated PI-3 virus/cell resulted in release of TNF- in significantly (P<0.05) higher amounts than sham-induced BAM. The quantities of TNF- released after live or UV-inactivated BHV-1 or BRSV induction were not significantly higher than sham-induced BAM. E. coli 0111:B4, P. haemolytica type 1 and P. multocida endotoxins stimulated TNF- release in a dose-dependent manner. Sequential exposure of BAM to 1 TCID50 per cell of either live BHV-1, PI-3 virus or BRSV and then 5 μg ml−1 of either E. coli 0111:B4, P. haemolytica type 1 or P. multocida endotoxin caused a significant (P<0.05) reduction in detectable TNF- in seven of nine virus/endotoxin combinations tested, when compared with 5 μg ml−1 of endotoxin alone. Parainfluenza-3 virus/endotoxin combinations stimulated higher TNF- release when compared with other virus/endotoxin combinations. Five out of six test animals had serum-neutralizing antibodies to PI-3 virus, one out of six had serum-neutralizing antibodies to BHV-1, and two out of six had serum-neutralizing antibodies to BRSV, suggesting a possible relationship between serum neutralizing antibodies and TNF- release from in vitro cultivated BAM.  相似文献   

217.
Eastern equine encephalitis (EEE) was diagnosed in a flock of emus in southeastern Louisiana. The outbreak involved juvenile and adult breeders ranging in age from 20 to 36 months, with an attack rate of 76% and a case fatality rate of 87%. The diagnosis was confirmed by isolation and characterization of the viral agent, and by detection of EEE antibody in two recovered emus. High mortality was preceded by marked depression, hemorrhagic diarrhea, and emesis of blood-stained ingesta. On postmortem examination, hemorrhagic enteritis and multiple petechia of viscera were observed. Microscopic changes included severe necrosis of hepatocytes, intestinal mucosa, and necrotizing vasculitis of the spleen and lamina propria of the intestine. No nervous system lesions were observed. This outbreak occurred concurrently with EEE in horses and was attributed to unseasonably heavy rainfall with an abundance of arthropod vectors and proximity to free-living reservoir host species.  相似文献   
218.
A genetically engineered Eimeria tenella antigen (GX3262), produced as a fusion protein with beta-galactosidase and identified with a monoclonal antibody, induced partial but significant protection in young broiler chickens against experimental E. tenella and Eimeria acervulina infections. The antigen appears to share a T-helper cell epitope with the parasite as evidenced by (a) booster inoculation with either the recombinant antigen or with a small number of live oocysts enhanced the protective immunity in GX3262 primed chickens, and (b) ability of the antigen to induce in vitro stimulation of T-cells from chickens immunized with antigen or parasite. These observations suggest the feasibility of a single vaccination of 1 or 2-day-old broilers with GX3262 to induce an acceptable degree of protective immunity. The implications of the observations reported here are far reaching in terms of a practical coccidiosis vaccine for poultry, and show for the first time that 1-day-old broiler chickens can be efficiently vaccinated with a recombinant antigen against one or more species of Eimeria.  相似文献   
219.
220.
Twenty-eight Norwegian Red Cattle dairy cows were fed silage ad libitum and restricted amounts of concentrates. Blood samples were collected before morning feeding, once or twice weekly, from 2 weeks before to 12 weeks after calving. Parameters of liver function, carbohydrate status and fertility were recorded in order to assess their interrelationships. Eight cows were treated for clinical ketosis. Four of these had to be treated 2 or 3 times. Aspartate aminotransferase and bilirubin showed the highest within-animal coefficients of correlation with acetoacetate. Analysis of variance revealed a significant effect of carbohydrate status (indicated by plasma acetoacetate levels) on the levels of aspartate aminotransferase, glutamate dehydrogenase and sorbitol dehydrogenase, though only a small part of the total variation was explained by this factor. The estimated volume density of liver fat in the 4th week of lactation averaged 6.0 +/- 6.4% (+/- SD) ranging from 0.1-25.1%. Liver fat content at this stage of lactation was not significantly correlated with other indicators of liver function or carbohydrate status. Cows treated for clinical ketosis had significantly lower plasma progesterone values at the time of first ketosis treatment than untreated multiparous cows. The frequency of high progesterone values (greater than 3 ng/ml) being significantly lower in treated than in untreated cows during the period from 3-5 weeks post partum, though not at later stages. In conclusion, the results revealed a significant relationship between carbohydrate status and liver function, and also between clinical ketosis and luteal function.  相似文献   
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