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841.
Up to now, prioritization of animals for conservation has been mainly based on pedigree information; however, genomic information may improve prioritization. In this study, we used two Holstein populations to investigate the consequences for genetic diversity when animals are prioritized with optimal contributions based on pedigree or genomic data and whether consequences are different at the chromosomal level. Selection with genomic kinships resulted in a higher conserved diversity, but differences were small. Largest differences were found when few animals were prioritized and when pedigree errors were present. We found more differences at the chromosomal level, where selection based on genomic kinships resulted in a higher conserved diversity for most chromosomes, but for some chromosomes, pedigree-based selection resulted in a higher conserved diversity. To optimize conservation strategies, genomic information can help to improve the selection of animals for conservation in those situations where pedigree information is unreliable or absent or when we want to conserve diversity at specific genome regions.  相似文献   
842.
Surgical castration is performed on most male piglets in the United States. However, castration is painful and analgesics have been considered to relieve pain. Inhalant gases with analgesic properties allow for a fast induction, have short-term and reversible effects, and are a needle-free option. Nitrous oxide (N(2)O; "laughing gas") has been widely used in human surgery and dental offices as an analgesic, sedative, and anxiolytic drug, yet N(2)O has not been thoroughly investigated for use in farm animals. We hypothesized that the analgesic effect of N(2)O could reduce the pain experienced by piglets during or immediately after castration. Twenty-four male piglets, from 12 litters, were castrated at 3 d of age. One piglet received N(2)O and a littermate received air as a control. After 150 s of exposure to the gas, castration was performed while the piglet remained exposed to the gas. Agitation scores and total vocalization length were recorded during castration. Behavioral observations were continued for 3 d postcastration by using a 5-min scan-sampling method for 4 h the first morning and for 2-h periods in the morning and afternoon of each day thereafter. Body weight gain was measured on the day before castration, at 3 d postcastration, and at weaning. Data were analyzed using a mixed model in SAS (Cary, NC). Nitrous oxide successfully induced anesthesia in all N(2)O piglets, as validated by a skin pinch test and the loss of the palpebral reflex. Total vocalization length was shorter in piglets receiving N(2)O during the induction phase (P = 0.003) but was not different during castration itself because piglets receiving N(2)O awoke and vocalized as much as control piglets (P = 0.87). Agitation scores during the whole procedure were reduced in piglets receiving N(2)O in both frequency (P = 0.005) and intensity (P = 0.026). For 2 h after castration, piglets receiving N(2)O displayed less huddling behavior than did control piglets (P = 0.01). Over the 3 d, piglets receiving N(2)O performed more tail wagging (P = 0.02) and tended to show fewer sleep spasms (P = 0.06) than did control piglets. Piglets given N(2)O tended to have a reduced growth rate compared with control piglets at 3 d postcastration and at weaning (P = 0.05 and P = 0.06, respectively). Nitrous oxide was effective in inducing anesthesia in neonatal piglets during handling. Nonetheless, its analgesic effects appeared insufficient in preventing castration-induced pain.  相似文献   
843.
Cats show a higher capability to supinate their forearms than dogs. This suggests a special arrangement of the collateral ligaments of the feline elbow joint. Therefore, the course of the ligaments was examined in 13 adult cats. The size of the ligaments was measured, and effects of passive joint movements were studied. Ligaments of five additional cats were examined histologically. The lateral collateral ligament (LCL) had a superficial and deep part, both originating from the humerus. The free humeral portion of the LCL was short and contained fibrous cartilage. Fibre bundles of the deep part inserted into the annular ligament, while the remaining deep fibres and the superficial part inserted with a long antebrachial portion on the radius. The medial collateral ligament (MCL) originated from the humeral epicondyle and divided into cranial and caudal parts. The caudal part inserted medioproximally on the ulna, while the cranial part attached primarily with a long thin part to the caudal aspect of the radius. During supination, the MCL loosened thus allowing medial widening of the joint space, up to 2 mm. A specific feature of the feline elbow is the long thin part of the MCL. Its course through a special furrow distal to the medial coronoid causes the tightening of the feline MCL during pronation. Apart from that, the feline collateral ligaments combine the features of both human and canine cubital anatomy. This explains the range of supination in cats, which is intermediate between humans and dogs.  相似文献   
844.
Superoxide anion radical, produced in low quantities, plays a positive role in sperm function. Spermatozoa produce superoxide anion radical during posttesticular development, which shows an abrupt increase during capacitation. The NAD phosphate oxidase (NOX) family members NOX2 and NOX5 are the 2 enzymes implicated in superoxide production in spermatozoa. We examined the organization of NOX2 in goat spermatozoa during epididymal maturation, capacitation, and acrosome reaction. Spermatozoa from testis, caput epididymidis, corpus epididymidis, and cauda epididymidis possessed components of the phagocytic oxidase (PHOX; i.e., gp91phox, p22phox, p67phox, p47phox, p40phox), and ras-related C3 botulinum toxin substrate 1/2 (Rac1/2) on spermatozoa, and their concentrations did not show significant alterations during epididymal maturation. During capacitation in vitro, p22phox underwent Thr-phosphorylation, which resulted in a mobility shift of the corresponding band toward greater molecular mass. The Rac1/2 also showed a mobility shift from 32 to 23 kDa during capacitation. During progesterone-induced acrosome reaction, the spermatozoa experienced a total loss of p22phox and p47phox. The p47phox, but not p22phox, was detected in the exocytic vesicles of the acrosome. The Thr-phosphorylated form of p22phox was ubiquitinated and degraded through proteasome-mediated pathways in goat sperm cell lysates. Thus, Thr phosphorylation of p22phox acts as a regulatory switch in goat spermatozoa that transiently activates the NOX2 system during capacitation and subsequently directs it for degradation through the ubiiquitin-proteasomal pathway during progesterone-induced acrosome reaction.  相似文献   
845.
Reasons for performing study: There is a need to assess the laminar inflammatory response in a laminitis model that more closely resembles clinical cases of sepsis‐related laminitis than the black walnut extract (BWE) model. Objectives: To determine if a similar pattern of laminar inflammation, characterised by proinflammatory cytokine expression, occurs in the CHO model of laminitis as has been previously reported for the BWE model. Methods: Sixteen horses administered 17.6 g of starch (85% corn starch/15% wood flour)/kg bwt via nasogastric (NG) tube were anaesthetised either after developing a temperature >38.9°C (DEV group, n = 8) or at onset of Obel grade 1 lameness (OG1 group, n = 8). Control horses (CON group, n = 8) were anaesthetised 24 h after NG administration of 6 l of deionised water. Laminar tissue was collected from horses while under anaesthesia, followed by humane euthanasia. Real time‐quantitative PCR was used to assess laminar mRNA concentrations of genes involved in inflammatory signalling. Results: Increased mRNA concentrations (P<0.05) for IL‐1β, IL‐6, IL‐12p35, COX‐2, E‐selectin and ICAM‐1 were present in laminae from horses with OG1 lameness but not at the DEV time, when compared to the CON horses. No differences between the groups were found for IL‐2, IL‐4, IL‐10, TNF‐α, IFN‐γ or COX‐1 at either the DEV or OG1 time points. Conclusions: There was a notable difference in the temporal pattern of inflammatory events between the BWE and CHO models, with the majority of laminar inflammatory events appearing to occur at or near the onset of lameness in the CHO model, whereas many of these events peak earlier in the developmental stages in the BWE model. This suggests that, in addition to circulating inflammatory molecules, there may be a local phenomenon in the CHO model resulting in the simultaneous onset of multiple laminar events including endothelial activation, leucocyte emigration and proinflammatory cytokine expression. Potential relevance: The similar (although somewhat delayed) inflammatory response in the CHO model of laminitis indicates that inflammatory signalling is a consistent entity in the pathophysiology of laminitis.  相似文献   
846.
The aim of the study was the electrophoretical identification of molecular forms of selected antioxidant enzymes in dog semen. Ejaculates to be studied were chosen from five dogs, aged from two to eight years. Polyacrylamide gel electrophoresis was carried out under non-denaturing conditions and then gels were stained for the activity of the following enzymes: superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx). Sperm homogenates and all fractions (pre-spermatic, spermatic and post-spermatic) of dog ejaculate demonstrated one protein band with SOD activity characterized by low electrophoretic mobility. Based on the confirmed sensitivity to H2O2, it can be assumed that the detected SOD is an enzyme containing ions of Zn2+ and Cu2+ (Cu,Zn SOD). In sperm homogenates one protein band with GPx activity was characterized by high electrophoretic mobility, whereas in the spermatic and post-spermatic fractions of dog ejaculate three protein bands with different (low, medium and high) electrophoretic mobility were identified. CAT molecular forms were not found in either sperm homogenates or in the analyzed fractions of ejaculate.  相似文献   
847.
848.
Reasons for performing study: There is little scientific information available about the ability of ocular disease to cause a systemic inflammatory response. Horses are frequently affected with ocular disease and ensuring their systemic health prior to performing vision saving surgery under anaesthesia is essential for the successful treatment of ophthalmic disease. Hypothesis: Ocular disease will cause elevations in the concentration of the acute phase proteins fibrinogen and serum amyloid A in peripheral blood. Methods: Whole blood and serum samples were obtained from 38 mature horses with ulcerative keratitis or uveitis and no evidence of systemic disease, 9 mature horses with no evidence of ocular or systemic disease (negative controls) and 10 mature horses with systemic inflammatory disease and no evidence of ocular disease (positive controls). Blood samples were assayed for concentrations of the acute phase proteins fibrinogen and serum amyloid A. Results: Fibrinogen and serum amyloid A were significantly different in the positive control group compared to the negative control, corneal disease and uveitis groups (P<0.126). There was no significant difference between the negative control, corneal disease and uveitis groups (P<0.001). Conclusions: Ulcerative keratitis and anterior uveitis are not associated with elevated concentrations of the acute phase proteins fibrinogen and serum amyloid A in peripheral blood. Potential relevance: When the clinician is presented with a patient with ocular disease and elevated plasma fibrinogen or serum amyloid A concentrations, a nonocular inflammatory focus should be suspected.  相似文献   
849.
Diseases in wildlife have been recognised as having the potential to affect human health, livestock health and species conservation. In order to assess and respond to these potential risks in an effective and a proportionate way, the UK Government initiated development of the Wildlife Health Strategy to provide a framework for decision making. The England Wildlife Health Strategy (EWHS) has been developed through extensive consultation. Discussions and negotiations with government departments, agencies, non-governmental public bodies and wildlife organisations were held to obtain advice and input on specific and specialised aspects of wildlife health. A series of workshops to investigate the application of innovative science to wildlife health policy contributed further. A formal public consultation was held that proposed a range of actions to implement the strategy. A summary of responses to this consultation was published in October 2007. The EWHS was published in June 2009 and provides a framework for a generic four-stage approach to wildlife health that can be adopted by decision makers both within and outside government.  相似文献   
850.
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