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941.
McDonnell PA Scott KG Teoh DA Olson ME Upcroft JA Upcroft P Buret AG 《Veterinary parasitology》2003,111(1):31-46
This study examines the ability of Giardia duodenalis trophozoites, isolated from a wild bird, to colonize the intestinal tracts of companion animals (kittens) and domestic ruminants (lambs). Trophozoites colonized the intestinal tracts of intraduodenally inoculated animals as demonstrated by increasing parasite burdens within the duodenum and jejunum and by fecal passage of cysts within 4 days post-inoculation. The pathogenesis of the trophozoites was further investigated in kittens. In these animals, infection significantly reduced jejunal brush border microvillous length and density, which resulted in a loss of overall epithelial brush border surface area. This injury was associated with the production of diarrhea in four of five infected kittens. These findings indicate that some bird species may carry G. duodenalis that represent a possible health threat to companion animals and livestock. Our results describe the first successful colonization of avian-derived G. duodenalis trophozoites in the small intestines of domestic kittens and lambs. 相似文献
942.
Six adult female chimpanzees (Pan troglodytes) were anaesthetised for the placement of intrauterine contraceptive devices, microchips for identification, routine blood sampling, and physical measurements. Anaesthesia was induced with medetomidine in combination with ketamine administered by intramuscular injection with a projectile syringe. Induction was smooth and rapid, but five of the animals were insufficiently relaxed for orotracheal intubation. The plane of anaesthesia was deepened by administering isoflurane delivered in oxygen and nitrous oxide, and general anaesthesia was maintained for up to 74 minutes. The action of medetomidine was reversed at the end of each procedure with atipamezole, and the animals recovered smoothly and uneventfully. 相似文献
943.
The prevalence of Theileria lestoquardi antibodies in Sudanese sheep from nine geographical areas in Sudan was determined using indirect fluorescent antibody "IFA" test. Out of 315 samples examined, 51 (16.2%) were found positive and ranged between 23.4% in River Nile State and 10% in Kasala and Darfour Provinces with an overall prevalence of 16.2% indicating widespread distribution of the infection. We also report on presence of antibodies reactive to Theileria annulata in sheep sera. 相似文献
944.
945.
M. Yamashita T. Osaki Y. Sunden K. Takahashi M. Ishizuka T. Tanaka L. Li Y. Okamoto 《The Journal of small animal practice》2020,61(8):516-519
Photodynamic detection using 5-aminolevulinic acid has been used to identify the surgical margins during resection of human primary brain tumours. Although there are some reports on its use in malignant tumours in veterinary medicine, it has never been used for primary brain tumours. Here we describe a canine glioblastoma that was detected at autopsy with protoporphyrin IX fluorescence induced by orally administered 5-aminolevulinic acid. The fluorescence was strongest towards the centre of the lesion and was absent in normal brain tissue. Moreover, the fluorescence findings were consistent with MRI and histopathological findings. Our findings suggest that photodynamic detection using 5-aminolevulinic acid might be useful for intraoperative fluorescence-guided resection of malignant gliomas in dogs. 相似文献
946.
947.
Rachel Pilla Frederic P. Gaschen James W. Barr Erin Olson Julia Honneffer Blake C. Guard Amanda B. Blake Dean Villanueva Mohammad R. Khattab Mustafa K. AlShawaqfeh Jonathan A. Lidbury Jörg M. Steiner Jan S. Suchodolski 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2020,34(5):1853-1866
948.
The objectives of this study were to estimate the environmental and additive and non-additive genetic effects on lactation curve and lactation parameters of crosses of Holstein (H), Brahman (B) and Brown Swiss (BS) in Olancho region in Honduras. The data consisted of 54,517 milk yield records from 192 dual-purpose crossbred cows lactating from 2000 to 2005 at the Universidad Nacional de Agricultura de Honduras (UNA). The lactation curve and lactation parameters of interest were the scaling factor to represent yield at the beginning of lactation (a), the factor associated with the inclining (b) and declining (c) slopes of the lactation curves, and the milk yield at initial day of lactation (MY20), peak milk yield (MYmax), day at peak milk yield (tmax), and the total milk yield (TM) per lactation, respectively. The incomplete gamma function (Wood function) was used to estimate lactation curve and lactation parameters from daily milk records of H × B, H × BS and BS × B crossbred cows. The environmental, additive and non-additive genetic effects on lactation curve and lactation parameters were estimated using Dickerson and Kinghorn models. The coefficients of determination of fitness of Wood's function (R2) ranged from 80% to 97% with an average of 93%. The lactation curve of the crossbred cows was similar to those reported for dairy cows grazing in the tropics. Lactation parameters such as MYmax, tmax and TM were significantly (P < 0.05) influenced by environmental sources of variation suggesting the necessity of differential management strategies. The moderate to large positive phenotypic correlation of MYmax and TM indicate that one of the milk yield parameters could be used as a selection criterion to improve either one or both traits. Despite the fact that both genetic models showed similar patterns, the absolute value of the parameters varied. For both models, individual additive genetic breed effect for H breed were significant (P < 0.05) and contributed more to TM than the BS breed. In the Dickerson model, highly positive significant (P < 0.01) effect on TM for H×BS and BS×B crosses was found. The Kinghorn model did not show significant effects of dominance on this parameter. The estimate of recombination effect for all crosses involving B breed were negative and significant (P < 0.05) for positive correlated lactation curve parameters. Although the inclusion of non-additive effects on crossbreeding genetic effects were not all significant for lactation curve and lactation parameters, non-additive effects should be taken into account to improve the Honduran dairy cattle production management. 相似文献
949.
950.
O. Balogh K. Kovcs M. Kulcsr A. Gsprdy H. Fbel A. Zsolnai L. Fsüs C. Delavaud Y. Chilliard R.O. Gilbert Gy. Huszenicza 《Livestock Science》2009,123(2-3):180-186
A polymorphic site of the growth hormone gene (AluI polymorphism) that results in an amino acid change at position 127 of the protein chain (leucine, L to valine, V) has been linked to differences in circulating metabolites and metabolic hormones of calves and bulls and to milk yield traits of lactating cows. Our objective was to investigate the interrelationship of this polymorphism with plasma concentrations of β-hydroxybutyrate, insulin, IGF-I and leptin in postpartum dairy cows. Blood samples were taken from clinically healthy, spring-calving, group-fed Holstein-Friesian cows (n = 257; 7 large-scale farms) 4–13 days after calving. Of all herds, 100 cows had plasma β-hydroxybutyrate levels above 1.2 mmol/l and 157 cows were normoketonemic. The proportion of valine carriers and LL cows was not different within groups of normo- and hyperketonemic animals. Genotype was not associated with plasma β-hydroxybutyrate, insulin, IGF-I and leptin levels either in all of the herds or in the two with the highest proportion of the valine allele carriers (n = 28, 72%). We found significantly lower insulin, IGF-I and leptin concentrations in the presence of hyperketonemia compared to normoketonemic cows. There were strong negative correlations between BHB and the other blood parameters, while insulin, IGF-I and leptin were positively related to each other. In conclusion, in the first two weeks after calving we could not demonstrate any effect of AluI polymorphism on plasma concentrations of β-hydroxybutyrate and metabolic hormones studied. Hyperketonemia was associated with a significant decrease in insulin, IGF-I and leptin blood levels. We infer that cows homozygous for the leucine allele or carrying the valine allele may have a similar endocrine and metabolic response to the challenge of increased nutrient demand early postpartum and that the presence of hyperketonemia is mainly linked to the hormonal and metabolic changes occurring at the onset of lactation. 相似文献