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991.
992.
Information is lacking regarding the relationship between metabolic and hormonal profiles and the maintenance of spontaneous ovarian cyst disease in dairy cows. For this reason, the concentrations of non‐esterified fatty acids (NEFA), insulin‐like growth factor I (IGF‐I) and cortisol (C) were investigated during the spontaneous course of ovarian cyst disease in dairy cows (n = 6) between the 7th and 16th weeks post‐partum (PP). The control group consisted of normally cycling cows (n = 6). Blood samples were collected twice a day, and plasma was analysed using different techniques. Progesterone and 15‐ketodihydro‐PGF plasma profiles were investigated to confirm the ovulatory or anovulatory conditions of the cows. Cortisol plasma levels were not significantly different among sampling times within each group or between the two groups. NEFA plasma levels were significantly higher in cycling cows compared to cystic cows at the 16th week PP (p < 0.01), but with rather low values, indicating by now sparse mobilization of fat stores. Insulin‐like growth factor I plasma concentrations were higher in cystic cows during the 8th, 10th, 11th (p < 0.01) and 16th week PP (p < 0.05), indicating that the presence of ovarian cysts coincides with increased IGF‐I levels. These results suggest no influence of cortisol and NEFA levels in cysts maintenance, while a possible involvement of IGF‐I can be suspected not only in the pathogenesis, as already known, but also in the maintenance of spontaneous cystic ovarian disease in cattle.  相似文献   
993.
Tropical Animal Health and Production - This study aimed to verify the reproductive seasonality in Saanen goats from distinct parity orders (nulliparous, primiparous, and pluriparous) throughout an...  相似文献   
994.
995.
996.
Following concomitant intravenous administration of Tomanol and sodium penicillin G to six Dutch Friesian dairy cows a significant decrease in total body clearance of penicillin (34.7%) and a prolongation of the elimination half-life of penicillin (17.2%) was observed. Tomanol did not affect other pharmacokinetic parameters such as rate constants of drug transfer (k12/k21, alpha en beta), distribution volume of the central compartment (V1), and extrapolated serum drug levels. Intravenous or intramuscular administration of Tomanol had no effect on the tissue distribution of penicillin G, because neither a change in the ratios of muscle to serum and of kidney cortex to serum nor a change in an induced steady state level of low penicilline G serum concentrations was observed. From the data obtained it is concluded that concomitant Tomanol administration with penicillin induces an elevation of the serum penicillin concentration and prolongs the persistence of penicillin residues in carcass meat and organs.  相似文献   
997.
998.
During the months of April to August in 1999 and 2002, oral swabs were collected from 146 tortoises (Testudo sp.) in private collections in the United Kingdom and tested by polymerase chain reaction (PCR) for the presence of Mycoplasma agassizii and Chelonian herpesvirus (ChHV). The presence of M. agassizii was confirmed by restriction digestion of the PCR product. A 307-bp fragment of the ChHV UL5 homologue gene was sequenced and found to show most similarity to equine herpesvirus type 1. A prevalence of 15.8 and 8.2% was found for M. agassizii and ChHV, respectively. Comparison of the carriage of both M. agassizii and ChHV in different species of tortoises correlated the presence of M. agassizii with Testudo horsfieldii and ChHV with Testudo marginata and Testudo graeca iberia. An association of ChHV with stomatitis was also found. Mixed infections with both agents were detected. The findings further demonstrate this pathogen-tortoise association and the cross transmission of these infections if different tortoise species are housed together.  相似文献   
999.
To study the relation between serum complement levels and the chicken MHC (B) complex, complement haemolytic activity was measured in sera from hens from seven pure-bred B-typed White and one Brown Leghorn lines, and three ISA-Warren lines that had been divergently selected for antibody responses to sheep red blood cells (SRBC). Significant differences occurred in the serum haemolytic complement activities, both belonging to the classic (CPW) and the alternative (APW) pathways, among the 11 different haplotyped chicken lines. Hens with high CPW and high APW titres predominantly displayed the B2 or B21 haplotypes. Chickens with low CPW and APW were found in B14 and B15 haplotypes. Haplotype B14 appears to be different in complement levels when present into the pure-bred lines or into the ISA-Warren line selected for low antibody responses to SRBC. Otherwise, the presence of B21 in ISA-Warren line selected for high antibody responses to SRBC does not differ with the B21 in the inbred lines (except in the NL-line for CPW values). In general the haplotypes B2 and B21 are found in chicken lines with enhanced disease resistance, and the B15 haplotype has been connected with enhanced disease susceptibility. Our results suggest that levels of haemolytic complement activity, either from the classical or from the alternative pathways, may underlie part of the immunocompetence ascribed to the MHC (B) complex in chickens.  相似文献   
1000.
OBJECTIVE: To report on progress in Johne's disease (JD) control in infected dairy herds participating in the Victorian Johne's disease Test and Control Program (TCP). PROCEDURE: Clinical histories and JD testing data recorded by the Department of Natural Resources and Environment (now called Department of Primary Industries) were analysed for 542 dairy herds participating in the TCP. The herds were required to conduct annual herd tests of cattle 2 years old and older with an enzyme linked immunosorbent assay (ELISA), cull the reactors and manage the younger cattle to minimise infection. RESULTS: Testing of over 680,000 animals identified over 10,000 reactors giving an average prevalence of reactors at the first whole-herd test (T1) of 1.78%. There was a relatively rapid increase in the incidence of clinical disease before the TCP started and then it markedly declined. There was a slow and interrupted decline in reactor prevalence, with a marked peak occurring at the fourth herd test (T4). The average age of reactors and clinical cases was 5.7 and 5.9 years, respectively. Of the reactors and clinical cases detected during the TCP, 87% and 95% respectively, were born before the TCP started. Thirty herds completed the program by achieving three successive negative whole herd tests and 91 herds dropped out because of inability to comply with the agreed requirements of the program. There were no home-bred reactors born after the start of the program in 253 (47%) herds and of the 522 herds that were tested more than once, there were 319 (61%) herds in which no home-bred reactors were detected after the first year of testing. The number of ELISA positive animals detected at T1 appeared to be only about 26% of the animals from that round that subsequently became positive or developed clinical disease at later test rounds. CONCLUSION: The TCP caused a marked decline in the number of clinical cases, probably because animals in which clinical disease was imminent were detected by testing and removed. A reduction in prevalence of reactors occurred only when most herd members were born after the TCP started. The sensitivity of the ELISA appears to be low based on the large number of reactors that were negative at T1 but were positive at later tests. Low sensitivity of diagnostic tests and the long incubation period of the disease limits meaningful analysis of the program until it has continued for some years. Measures adopted in the TCP have not broken the cycle of infection in many participating herds. It is unsure if this was because of poor compliance with control recommendations or a poor understanding of methods of transmission by scientists. Eradication is not feasible in the short-term.  相似文献   
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