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51.
This paper's objectives were to estimate the genetic (co)variance components of the Gompertz growth curve parameters and to evaluate the relationship of estimated breeding values (EBV) based on average daily gain (ADG) and Gompertz growth curves. Finnish Yorkshire central test station performance data was obtained from the Faba Breeding (Vantaa, Finland). The final data set included 121,488 weight records from 10,111 pigs. Heritability estimates for the Gompertz growth parameters mature weight (alpha), logarithm of mature weight to birth weight ratio (beta) and maturation rate (kappa) were 0.44, 0.55 and 0.31, respectively. Genotypic and phenotypic correlations between the growth curve parameters were high and mainly negative. The only positive relationship was found between alpha and beta. Pearson and Spearman rank correlation coefficients between EBV for ADG and daily gain calculated from Gompertz growth curves were 0.79. The Spearman rank correlation between the sire EBV for ADG and Gompertz growth curve parameter-based ADG for all sires with at least 15 progeny was 0.86. Growth curves differ significantly between individuals and this information could be utilized for selection purposes when improving growth rate in pigs.  相似文献   
52.
A 7‐year‐old intact male Boxer was referred to our services at the Veterinary Teaching Hospital of the University of Trás‐os‐Montes and Alto Douro, suffering from a persistently erect penis (including the bulbus glandis) that had been exposed for several days. Radiographic and ultrasonographic examinations detected a 5.0 × 3.5 cm mass located dorso‐laterally to the urinary bladder. The microbial culture of the mass revealed Staphylococcus spp. At that time, we suspected the involvement of an abscess in the origin of the priapism. Medical and surgical treatments were promptly instituted, which allowed for penile withdrawal into the prepuce; however, the resolution of the penile erection was not accomplished in the following days and penile amputation was required. Histological evaluation of the excised penis revealed extensive infarction of the erectile tissue of the pars longa and bulbus glandis, and also of the blood vessels of the penis. Following penile amputation and antimicrobial therapy, the animal fully recovered. Ultimately, the animal died as a consequence of gastric torsion. At necropsy, some lesions compatible with a previous perforation of the intestinal wall were recorded. The data gathered from the anamnesis, the physical and imaging examinations, along with the post‐mortem findings, allowed us to conclude that in this clinical case the primary cause of priapism was a perineal abscess due to bowel perforation.  相似文献   
53.
Oxidative stress represents a challenge during sperm manipulation. We have tested the effect of increasing hydrogen peroxide (H2O2) levels on red deer spermatozoa after cryopreservation, and the role of male‐to‐male variation in that response. In a first experiment, eight thawed samples were submitted to 0, 25, 50, 100 and 200 μm H2O2 for 2 h at 37°C. Intracellular reactive oxygen species (H2DCFDA‐CM) increased with H2O2 concentration, but we only detected a decrease in sperm function (motility by CASA and chromatin damage by sperm chromatin structure assay) with 200 μm . Lipoperoxidation assessed by the thiobarbituric acid reactive substance (TBARS) method increased slightly with 50 μm H2O2 and above. In a second experiment, samples from seven males were submitted to 0 and 200 μm H2O2 for 2 h, triplicating the experiment within each male. Males differed at thawing and regarding their response to incubation and H2O2 presence. We found that the kinematic parameters reflected male‐to‐male variability, whereas the response of the different males was similar for lipid peroxidation and viability. A multiparametric analysis showed that males grouped differently if samples were assessed after thawing, after incubation without H2O2 or after incubation with H2O2. Red deer spermatozoa are relatively resilient to H2O2 after thawing, but it seems to be a great male‐to‐male variability regarding the response to oxidative stress. The acknowledgement of this individual variability might improve the development of optimized sperm work protocols.  相似文献   
54.
The goal of this study was to investigate for the first time a possible association between plasma concentrations of testosterone and total estrogen and testicular blood flow in the stallion. Correlations between these variables were calculated before and after administration of human chorionic gonadotropin (hCG). Eight mature warmblood stallions received 5,000 IU hCG intravenously, and four stallions received solvent only. Testicular blood flow in the left and right testicular arteries was assessed using colour Doppler sonography by measuring blood flow volume (BFV) and pulsatility index (PI) immediately before (time 0) and 1, 3, 6, 12, 24, 72, 120 and 168 h after hCG administration. EDTA blood samples were collected after each examination from a jugular vein to measure plasma testosterone and total estrogen concentrations. After treatment, the BFV increased and was elevated at 1 h and between 12 and 24 h. The profile of the PI was contrary to that of the BFV throughout the study period. Following hCG, there was a biphasic increase in testosterone concentration with maxima between 1 and 3 h and between 24 and 72 h, and there was a monophasic increase in the total estrogen concentration with a maximum between 6 and 24 h. At time 0, the total estrogen concentration correlated significantly with BFV (r=0.90; P<0.05) but the testosterone concentration did not (P>0.05). The testosterone and total estrogen concentrations did not correlate with PI (P>0.05). The total estrogen concentration, but not testosterone, correlated well with BFV after injection of hCG (P<0.05). The results of this study indicated that the testicular blood flow volume of the stallion may be regulated by estrogens, but additional studies are necessary to investigate whether there is a causal relationship.  相似文献   
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The aim of the present study is to identify ostrich sex by using polymerase chain reaction (PCR) on micro amounts of DNA from blood, bloodstain and feathers. Sixteen male and 18 female ostriches were used as test individuals. Genomic DNA as a template was extracted by the Chelex method. Ostrsex‐P1 and P2 primers were designed to perform PCR amplification on the template. PCR products were checked using agarose gel electrophoresis with ethidium bromide staining and ostrich sex was determined directly by the bands shown on the gel. The results demonstrate that ostrich sex can be determined by the extraction of DNA from as little as 0.0125 μl blood using Chelex, whereby the use of large amounts of organic solvents such as phenol and chloroform are unnecessary. In addition, it is possible to identify ostrich sex using micro amounts of DNA extracted from bloodstains and/or feathers. The use of feathers particularly avoids unwanted sampling problems such as the difficulty of collecting ostrich blood, the stress to the ostrich caused by bleeding, and the demand for a lot of manpower for ostrich restraint.  相似文献   
58.
Companion animals are exposed to similar environmental conditions and carcinogens as humans. In some animal cancers, there also appears to be the same genetic changes associated as in humans. However, little work has been carried out in cancer biomarker identification in animals. The recent dramatic advances in molecular medicine, genomics, proteomics and translational research will allow biomarker identification, which may provide the best strategies for veterinarians and clinicians to combat disease by early diagnosis and administration of effective treatments. Proteomics may have important applications in cancer diagnosis, prognosis and predictive clinical outcome that could directly change clinical practice by affecting critical elemen‐ts of care and management. This review summarizes the advances in proteomics that has propelled us to this exciting age of clinical proteomics, and highlights the future work that is required for this to become a reality. In this review, we will discuss the available proteomic technologies and their limitations, and highlight the key areas of research and how they have been used to discover cancer biomarkers. The principles described here are equally applicable to human and animal disease, but implementation of ‘omic’ technologies requires stringent guidelines for collection of clinical material, the application of analytical techniques and interpretation of the data.  相似文献   
59.
Coccidia in cows and calves on pasture in north Georgia (U.S.A.)   总被引:2,自引:0,他引:2  
The prevalence and abundance of coccidian oocysts were determined in a herd of beef cows and calves on fescue pastures in the Piedmont area of Georgia during 4-consecutive grazing seasons. Twelve species of Eimeria were found in the feces of the calves and 10 species were found in the feces of the cows. Eimeria bovis was the most prevalent species found in both the calves and cows. It occurred in 72.5% of 1090 samples from the calves and 10.2% of 719 samples from cows. Eimeria bovis also comprised the majority of oocysts present in the fecal samples from the calves and cows. The greatest number of E. bovis in a sample was 45 800 oocysts per gram of feces (OPG) from a calf and 1900 OPG from a cow. No cases of clinical coccidiosis were seen in any of the animals sampled during the survey.  相似文献   
60.
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