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191.
Contrary to expectation, immunoconglutinin levels failed to rise significantly in calves infected with Trypanosoma congolense. In addition, it was shown that trypanosome infection appeared to inhibit the immunoconglutinin response to Brucella abortus strain 19. The possible reasons for these findings are discussed.  相似文献   
192.
193.
The caecum and the adjacent 30 cm lengths of ileum and large colon of 201 horses from two different regions of Norway (Østlandet and Trøndelag) were examined for the presence ofAnoplocephala perfoliata. In all, 20% of the horses were infested with the cestode (27% in Østlandet and 7% in Trøndelag). The mean number of worms in infected horses from the two regions was 18 and 6, respectively.Information was obtained on the age, sex, breed, type of pasture and anthelmintic treatment after the grazing season for 183 of the 20 horses. The degree of infestation withA. perfoliata was not influenced by age, breed or sex. The odds ratio (confidence limits) for using permanent pastures that had been grazed by horses for at least the 5 last years in succession was 8.8 (3.2–24.4). There was a significantly higher prevalence ofA. perfoliata infestation in Østlandet (odds ratio 3.1 (1.1–9.1). The relatively low prevalence ofA. perfoliata infestation in Norwegian horses compared to the reported prevalences in other countries and the differences in the prevalence between Østlandet and Trøndelag are discussed. Gross pathological examination identified lesions such as mucosal thickening, hyperaemia and/or erosions. These lesions were found in all of the infected horses, compared with only 5% of the non-infected horses.Examination of faecal samples from 26 of the infected horses detected cestode eggs in only three cases. It was concluded that faecal examination is an inadequate method for the diagnosis ofA. perfoliata infestation.  相似文献   
194.
Selection for body weight at 49 day of age ( s and h , downward selected lines; s' and h' , upward selected lines) affected reproductive traits in CF1 mice lines. The objective of this study was to compare ovarian structures in females of these lines, as well as in unselected controls (Line t ). The number of ovarian follicles ( N ), follicle diameter (FD), number of corpora lutea (CL), litter size (LS), and body weight ( W ), were recorded. There were significant differences among lines for N , FD, CL, LS and W ; means values for the lines with the greatest difference for post-pubertal females were: N s  = 19.3 and N s'  = 32.7; FD h'   = 161.7 and FD s'  = 178.2; CL h  = 10.3 and CL s'  = 21.9; LS s  = 6.0 and LS h'  = 11.1; W h  = 18.9 and W s'  = 32.4. There were also differences between positive lines; Line s' had a higher proportion of large follicles in pre-pubertal females, a greater capacity to convert these follicles into CL, but a lower capacity to maintain embryos until term than Line h' . For negative lines, Line h apparently had a reduced incidence of embryonic loss when compared with Line s . In conclusion, selection for body weight modified ovarian structure, as well as reproductive efficiency.  相似文献   
195.
Pregnancy is characterized by transient changes in the maternal immune system, also evident at peripheral level. The present study analyzes the kinetics and possible factors affecting peripheral white blood cell populations throughout pregnancy in a herd of high-producing dairy cows chronically infected or not with Neospora caninum. We examined 54 pregnant parous cows: 29 Neospora-seronegative and 25 Neospora-seropositive cows. Blood samples were collected on Days 90, 120, 150, 180 and 210 of gestation. General Linear Model (GLM) repeated measures analysis of variance showed that the interaction Neospora-seropositivity × parity significantly affected total leukocyte, neutrophil and monocyte counts with lower levels of total leukocytes, lower neutrophil and higher monocyte counts recorded in primiparous Neospora-seropositive cows. In addition, N. caninum-seropositive cows had significantly increased monocyte counts on Day 180 of gestation compared to seronegative ones. Other factors significantly associated with changes in total and/or differential leukocyte profiles were period of pregnancy, season, twin pregnancy and milk production. In conclusion, a parity-associated effect of chronic N. caninum infection was observed on peripheral blood cell profiles in dairy cattle during gestation.  相似文献   
196.
A 5-month-old female Great Dane puppy was treated for hematochezia, tenesmus, and rectal prolapse by resection of a 10-cm-long segment of colon and rectum. Grossly, the colorectal segment had diffuse mucosal and submucosal thickening with multiple polypoid nodules. The histologic diagnosis was colorectal hamartomatous polyps with ganglioneuromatosis. Duplication of PTEN was detected by quantitative multiplex polymerase chain reaction testing. The presence of 2 hamartomatous colorectal lesions with PTEN mutation is similar to human Cowden syndrome.  相似文献   
197.
1. The role of beta2-agonist and of cAMP in chick skeletal muscle proteolytic pathways and protein synthesis was investigated using an in vitro preparation that maintains tissue glycogen stores and metabolic activity for several hours. 2. In extensor digitorum longus (EDL) muscle total proteolysis decreased by 15 to 20% in the presence of equimolar concentrations of epinephrine, clenbuterol, a selective hbetaagonist, or dibutyryl-cAMP. Rates of protein synthesis were not altered by clenbuterol or dibutyryl-cAMP. 3. The decrease in the rate of total protein degradation induced by 10(-5)M clenbuterol was paralleled by a 44% reduction in Ca2+-dependent proteolysis, which was prevented by 10(-5)M ICI 118.551, a selective fbeta2antagonist. 4. No change was observed in the activity of the lysosomal, ATP-dependent, and ATP-independent proteolytic systems. Ca2+-dependent proteolytic activity was also reduced by 58% in the presence of 10(-4)M dibutyryl-cAMP or isobutylmethylxanthine. 5. The data suggest that catecholamines exert an inhibitory control of Ca2+-dependent proteolysis in chick skeletal muscle, probably mediated by fbeta2adrenoceptors, with the participation of a cAMP-dependent pathway.  相似文献   
198.
The 1998 Report of the American Association of Feline Practitioners and Academy of Feline Medicine Advisory Panel on Feline Vaccines was developed to help veterinary practitioners formulate vaccination protocols for cats. The current panel report updates information, addresses questions, and speaks to concerns raised by the 1998 report. In addition it reviews vaccine licensing, labeling, and liability issues and suggests ways to successfully incorporate vaccination protocol changes into a private practice setting.  相似文献   
199.
AIMS: To evaluate the effectiveness of treatment programmes that included controlled internal drug-releasing (CIDR) devices containing progesterone (P4) in improving synchrony of oestrus, and conception and pregnancy rates in cycling, anoestrous and inseminated dairy cows, using meta-analysis. To describe the difference in response between cycling and anoestrous cows to CIDR-based synchrony programmes. METHODS: Scientific papers written in the English language between 1989 and 2002 that investigated the effects of treatment programmes including CIDR devices on reproductive performance in dairy heifers or lactating dairy cows were identified using a computerised literature search. The criteria for inclusion incorporated evidence that treatment allocation was completely randomised; the population studied was lactating dairy cows; and that data were available on submission, conception and pregnancy rates and their associated measures of variability. Reproductive outcomes from 25 synchrony trials (total n=11,058 cows) were analysed. Summary measures of the effect of treatment on reproductive outcome were assessed using fixed- and random-effects Bayesian meta-analysis models. RESULTS: Treatment programmes including a CIDR device increased the risk of submission in cycling cows (predicted Bayesian RR=2.86, 95% credible interval=1.46-5.67). Compared with controls, synchrony programmes including CIDR devices in cycling dairy cows had no effect on the risk of conception to first service post-treatment (predicted Bayesian RR=1.00, 95% credible interval=0.80-1.24). Compared with controls, synchrony programmes including CIDR devices had no effect on the risk of pregnancy throughout the mating period (predicted Bayesian RR=1.02, 95% credible interval=0.89-1.17). In anoestrous cows, CIDR treatment had no effect on the risk of conception to first service post-treatment and no effect on the risk of pregnancy throughout the mating period, compared with anoestrous, untreated controls (predicted Bayesian RR=0.91 and 0.97, respectively; 95% credible interval=0.68-1.26 and 0.59-1.60, respectively). CONCLUSION: The results of this meta-analysis showed that synchrony programmes using CIDR devices combined with other hormones reliably enhanced submission rates in lactating dairy cows. The relatively small number of trials with data suitable for analysis and the heterogeneity of results at the individual trial level limited our ability to confirm either a beneficial or deleterious effect of treatment on conception or pregnancy rates. Further randomised, controlled trials to evaluate the effectiveness of this form of reproductive therapy in commercial dairy farms are needed.  相似文献   
200.
Infection with Babesia bovis was diagnosed in a 2‐day‐old female calf apparently transmitted in utero. The calf was born as the second calving to a cross‐bred beef cow permanently on pasture. Diagnosis was based upon identification of B. bovis in peripheral blood smears and clinical signs which included fever, jaundice, pale mucous membranes and convulsions. Anaemia, leucocytosis, thrombocytopenia and lymphocytosis were noted at the febrile acute stage of the disease. The blood smears revealed evidence of regeneration of toxic neutrophils with a left shift, severe spherocytosis and high degree of basophilic stippling. Elevated concentration of aspartate aminotransferase, lactate dehydrogenase, and creatine kinase were also noted, and were probably the result of haemolysis, dehydration and muscle damage because of recumbancy. Elevated total bilirubin concentration following haemolysis resulted in jaundice. The neurological symptoms observed were probably caused by sludging of parasitized erythrocytes in the brain capillaries. The calf recovered following treatment with diminazene aceturate and the recovery was followed up clinically, haematologically and biochemically.  相似文献   
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