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1.
Flow cytometric sorting technology was used to measure the difference in DNA content between X- and Y-chromosome-bearing spermatozoa in bucks. Spermatozoa were analysed by flow cytometry to characterize X- and Y-chromosome-bearing sperm populations and to quantify the DNA difference between them. Two symmetrical, overlapping and clearly separated peaks, corresponding to X- and Y-bearing spermatozoa, were detected. The difference in fluorescence intensity between the peaks was 4.4 +/- 0.03% without any significant inter- or intra-animal variations. Therefore, the identification and selection of high-purity samples of sperm populations for sex sorting is easier in bucks compared with other domestic species. 相似文献
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Key Factors Affecting Reproductive Success of Thoroughbred Mares and Stallions on a Commercial Stud Farm 下载免费PDF全文
EA Lane MLJ Bijnen M Osborne SJ More ISF Henderson P Duffy MA Crowe 《Reproduction in domestic animals》2016,51(2):181-187
To evaluate factors contributing to fertility of thoroughbred mares, data from 3743 oestrous periods of 2385 mares were collected on a large thoroughbred farm in Ireland. Fourteen stallions (mean age 8.3 years; range 4–15 years) had bred 2385 mares (mean age 9.4 years; range 3–24 years). Maiden mares accounted for 12%, mares with a foal at foot for 64%, and barren, slipped or rested mares for 24% of the total. The mean pregnancy rate per cycle was 67.8% (68.6% in year 1 and 66.9% in year 2). Backward stepwise multivariable logistic regression analysis was utilized to develop two models to evaluate mare factors, including mare age, reproductive status, month of foaling, dystocia, month of cover, foal heat, cycle number, treatments, walk‐in status and stallion factors including stallion identity, stallion age, shuttle status, time elapsed between covers and high stallion usage on the per cycle pregnancy rate and pregnancy loss. Old age (p < 0.001) and cover within 20 days post‐partum (p < 0.003) were associated with lowered pregnancy rates. High mare age (p < 0.05) and barren, slipped or rested reproductive status (p = 0.05) increased the likelihood of pregnancy loss. Uterine inflammation or infection, if appropriately treated, did not affect fertility. Only high usage of stallions (used more than 21 times in previous week) was associated with lowered (p = 0.009) pregnancy rates. However, shuttle stallions were more likely to have increased (p = 0.035) pregnancy survival, perhaps reflecting a bias in stallion selection. In conclusion, mare age exerted the greatest influence on fertility; nonetheless, thoroughbreds can be effectively managed to achieve high reproductive performance in a commercial setting. 相似文献
3.
Factors affecting the success rate of treatment of recumbent dairy cows suffering from hypocalcaemia
Gelfert CC Alpers I Dallmeyer M Decker M Hüting A Lesch S Baumgartner W Staufenbiel R 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2007,54(4):191-198
We aimed to investigate the ratio of accompanying diseases in cows suffering from clinical hypocalcaemia and their influence on cure rate. In five veterinary practices in different regions of Germany, all recumbent cows around parturition were included in the study for a period of 1 year. After recording the case history a clinical examination was done and a serum sample was taken to measure the concentrations of calcium and phosphorus magnesium, beta-hydroxybutyrate, total bilirubin, cholesterol, urea, and the activities of ASAT, CK, and GLDH. Only cows with hypocalcaemia entered the statistical analysis. Hypocalcaemia was the major cause of recumbency in cows of the second lactation or elder. Muscle damage was the second frequent diagnose in recumbent cows and the major concomitant disease in hypocalcaemic cows. The overall cure rate was between 89.4% and 94.8%. Calcium and phosphorus concentrations did not have an influence on cure rate. Non-cured cows had higher serum activities of CK (p<0.043) and ASAT (p<0.006). Nevertheless, the activities of CK and ASAT were no good predictors of treatment failure because of their low specificity and the high cure rate of the cows in the five practices. 相似文献
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Objective To characterise the effects of delmadinone acetate on the pituitary-adrenal axis, glucose tolerance and growth hormone concentration in normal male dogs and dogs with benign prostatic hyperplasia.
Design A prospective study involving nine normal male dogs and seven with prostatic hyperplasia.
Procedure Delmadinone acetate was administered to six normal male dogs and seven dogs with benign prostatic hyperplasia at recommended dose rates (1.5 mg/kg subcuta-neously at 0, 1 and 4 weeks). Three normal controls received saline at the same intervals. Blood concentrations of ACTH, cortisol, glucose, insulin and growth hormone were measured over 50 days. Intravenous glucose tolerance and ACTH response tests were performed before and after treatment in the nine normal animals.
Results A substantial suppression of basal and 2 h post-ACTH plasma cortisol secretion was demonstrated after one dose in all dogs given delmadinone acetate. Individual responses after the second and third administration varied between recovery in adrenal responsiveness to continued suppression. Plasma ACTH concentration was also diminished after one treatment. No effects were evident on glucose tolerance or serum growth hormone concentrations.
Conclusion Delmadinone acetate causes adrenal suppression from inhibition of release of ACTH from the pituitary gland. Treated dogs may be at risk of developing signs of glucocorticoid insufficiency if subjected to stressful events during or after therapy. Neither glucose intolerance nor hyper-somatotropism seems likely in male dogs given delmadinone acetate at the recommended dose rate, but the potential for excessive growth hormone secretion in treated bitches remains undetermined. 相似文献
Design A prospective study involving nine normal male dogs and seven with prostatic hyperplasia.
Procedure Delmadinone acetate was administered to six normal male dogs and seven dogs with benign prostatic hyperplasia at recommended dose rates (1.5 mg/kg subcuta-neously at 0, 1 and 4 weeks). Three normal controls received saline at the same intervals. Blood concentrations of ACTH, cortisol, glucose, insulin and growth hormone were measured over 50 days. Intravenous glucose tolerance and ACTH response tests were performed before and after treatment in the nine normal animals.
Results A substantial suppression of basal and 2 h post-ACTH plasma cortisol secretion was demonstrated after one dose in all dogs given delmadinone acetate. Individual responses after the second and third administration varied between recovery in adrenal responsiveness to continued suppression. Plasma ACTH concentration was also diminished after one treatment. No effects were evident on glucose tolerance or serum growth hormone concentrations.
Conclusion Delmadinone acetate causes adrenal suppression from inhibition of release of ACTH from the pituitary gland. Treated dogs may be at risk of developing signs of glucocorticoid insufficiency if subjected to stressful events during or after therapy. Neither glucose intolerance nor hyper-somatotropism seems likely in male dogs given delmadinone acetate at the recommended dose rate, but the potential for excessive growth hormone secretion in treated bitches remains undetermined. 相似文献
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Extraction and characterization of oil bodies from soy beans: a natural source of pre-emulsified soybean oil 总被引:1,自引:0,他引:1
Iwanaga D Gray DA Fisk ID Decker EA Weiss J McClements DJ 《Journal of agricultural and food chemistry》2007,55(21):8711-8716
Soybeans contain oil bodies that are coated by a layer of oleosin proteins. In nature, this protein coating protects the oil bodies from environmental stresses and may be utilized by food manufacturers for the same purpose. In this study, oil bodies were extracted from soybean using an aqueous extraction method that involved blending, dispersion (pH 8.6), filtration, and centrifugation steps. The influence of NaCl (0-250 mM), thermal processing (30-90 degrees C, 20 min) and pH (2-8) on the properties and stability of the oil bodies was analyzed using zeta-potential, particle size, and creaming stability measurements. The extracted oil bodies were relatively small ( d 32 approximately 250 nm), and their zeta-potential went from around +12 mV to -20 mV as the pH was increased from 2 to 8, with an isoelectric point around pH 4. The oil bodies were stable to aggregation and creaming at low (pH = 2) and high (pH >/= 6) pH values but were unstable at intermediate values (3 = pH = 5), which was attributed to their relatively low zeta-potential. The oil bodies were stable to aggregation and creaming at relatively low salt concentrations (NaCl = 25 mM, pH 7) but were unstable at higher values as a result of electrostatic screening effects. The oil bodies were stable to thermal processing from 30 to 90 degrees C (0 mM NaCl, pH 7), but there appeared to be a change in their interfacial properties (decrease in zeta-potential) at temperatures exceeding 60 degrees C. These results suggest that oil bodies extracted from soybeans have similar or improved stability compared to soybean oil emulsions produced from bulk ingredients and may provide a new way of creating functional soy products for the food industry. 相似文献
8.
EA Ordoñez‐Leon H Merchant A Medrano M Kjelland S Romo 《Reproduction in domestic animals》2014,49(2):306-314
The aim of this study was to quantify the content of lipid droplets in bovine oocytes and embryos from Bos indicus (Bi), Bos taurus (Bt) and Bos indicus × Bos taurus (Bi × Bt). Oocytes were aspirated post‐mortem and subjected to in vitro maturation, in vitro fertilization and in vitro development; the medium employed at each stage (TCM‐199, TALP, SOF) was supplemented with (i) serum replacement (SR), (ii) foetal calf serum (FCS) or (iii) oestrous cow serum (ECS). The structure and distribution of the lipid droplets were established using electron microscopy, but were quantified using an optical microscope on semi‐fine toluidine blue‐stained sections. The highest percentage of embryos corresponded to those produced with FCS and ECS, which differed from embryos generated with SR (p < 0.05). The highest percentage of morulae and the lowest percentage of blastocysts were obtained with the SR supplement (p < 0.05). The oocytes cultured in FCS demonstrated a higher number of lipid droplets compared to those cultured in SR and ECS (p < 0.05). Less accumulation of lipids was observed in embryos supplemented with SR. The lowest and highest numbers of lipid droplets in oocytes corresponded to the Bi and Bt strain, respectively. The lowest amount of lipid droplets in embryos was observed in Bi (p < 0.05). In conclusion, supplementation of the in vitro development culture medium (synthetic oviduct fluid) with a synthetic substitute serum produced similar results in terms of embryo development compared to those obtained with FCS, but a decreased degree of lipid droplet accumulation was observed in the in vitro‐cultured embryos. 相似文献
9.
Emily F. Pomeranz Daniel J. Decker William F. Siemer Arthur Kirsch Jeremy Hurst James Farquhar 《Human Dimensions of Wildlife》2014,19(5):448-457
The trend in wildlife management over the last two decades has been to develop locally based approaches for responsiveness to local conditions, but some state wildlife agencies are finding the amount of staff time required to service this approach prohibitive. Although local engagement strategies have been lauded as assuring that public trust obligations of state government to citizens are met, we can expect that states with a local focus as their operational level of stakeholder engagement may opt to change their approach to reflect their resource limitations. We argue for comprehensive regional level effort to understand stakeholders augmented with local engagement processes where needed to deal with special circumstances in smaller areas within a region. Such an approach can be anticipated to have implications for stakeholder engagement and human dimensions research needs, which we discuss in the context of public trust resource administration and good governance of wildlife resources. 相似文献
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