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1.
Egg yolk is a common additive to sperm cryopreservation diluents. Because of its animal origin, however, it also represents a potential risk of microbiological contamination in the diluent. This potential contamination can be avoided by using powdered egg yolk, instead of fresh egg yolk, as it is pasteurized. This study was conducted to determine ram sperm cryosurvival was affected by the type of egg yolk used (powdered egg yolk or fresh egg yolk) and by yolk concentration (10, 15 or 20%) in the diluent. Microbiological analyses were also performed to quantify the microbiological contamination in the diluents containing the two types of egg yolk. Sperm cryosurvival was determined by motility and morphology analyses after thawing. Motility parameters were assessed using a computer-assisted sperm analysis (CASA) system, and the percentage of sperm with a normal apical ridge was evaluated using a differential interference contrast microscope. No significant differences were observed between diluents in the percentage of sperm with normal apical ridge. However, higher percentages of total motile cells were observed for samples containing powdered egg yolk (69%) compared to samples containing fresh egg yolk (60%). However, sperm in diluents containing fresh egg yolk, exhibited higher values for average-path velocity, straight-line velocity and beat cross frequency and lower values for amplitude of lateral head displacement (p <0.05), compared to cells in diluents containing powdered egg yolk. Microbiological contamination was similar (<200 CFU/ml) in both diluents, and no bacterial growth was observed in either, when antibiotics were added. Therefore, powdered egg yolk can be effective used in diluents for the freezing of ram semen. However, the in vivo fertility of sperm frozen in diluents containing powdered egg yolk should be tested, as some motility parameters were different for sperm treated with powdered egg yolk compared to fresh egg yolk.  相似文献   
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Hemophilia A in three unrelated cats   总被引:1,自引:0,他引:1  
Factor VIII deficiency, consistent with hemophilia A, was detected in 3 unrelated male domestic short-haired cats. Clinical history of each case differed and illustrated the spectrum of clinical manifestations of this disease in cats. Clinical expression of feline hemophilia A was similar to that of man and other animals, in which the degree of factor VIII deficiency tends to determine the severity and frequency of bleeding. All 3 cats had severe protracted bleeding after minor surgical procedures. Hemorrhage was eventually controlled in each case by transfusions of fresh whole blood.  相似文献   
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An epidemiological investigation of an outbreak of intestinal atresia in Israeli Holstein-Friesian newborn calves showed a linkage with rectal palpation for early pregnancy diagnosis, performed less than 42 days after insemination. The odds of an exposed calf, i.e., one born to a dam that was diagnosed by early palpation as having intestinal atresia were 119.7 times higher than one born in normal control herds (95% CI; 7.4-1946.3). A total of 682 calves-at-risk was recorded from mid-1998 to mid-2000 and a total of 47 calves (6.9%) were born with intestinal atresia during this period. Two forms of intestinal atresia were recognized at post-mortem: atresia coli and atresia ilei.  相似文献   
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The influence of three diets, comprising dam's milk (DM) from the same farm, commercial milk replacer with (CMRL) or without 3.2% lactose (CMR), on the duration and intensity of Candida glabrata shedding in the faeces of preweaned calves following experimental oral infection was examined. Shedding of other potential enteric pathogens was also monitored. The duration and intensity of C. glabrata shedding in DM-fed calves were reduced significantly compared with the calves fed the two diets based on milk replacers. Consequently, feeding calves with DM might disrupt the infective cycle, resulting in the yeast's elimination from a farm. In the CMR and CMRL groups, the periods of intensive shedding of C. glabrata and rotavirus overlapped but no diarrhoea was associated with the shedding of either microorganism. There was no evidence that lactose diminished colonization in vivo.  相似文献   
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An adult male black-necked swan (Cygnus melanocoryphus) was evaluated for a routine physical examination and West Nile virus vaccination. Nine days later, the swan was hospitalized for weakness, dehydration, tremors, and leukocytosis. Gradual clinical improvement was seen over a 2-wk course of supportive care. However, the animal became acutely weak and was found dead. Histopathology revealed severe granulomatous pneumonia and air sacculitis with dissemination to the liver, spleen, intestine, and coelom. Mycobacterial infection was confirmed by identification of acid-fast bacilli within tissue sections and by polymerase chain reaction. Concurrent West Nile virus infection was identified in sections of brain by using immunohistochemistry.  相似文献   
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Objective To determine practices for control of louse infestation and blowfly strike in Queensland sheep flocks that are associated with organophosphorous and synthetic pyrethroid residues on wool.
Design Information on residues was obtained from a survey of Queensland wool clips. Information on pesticide use was obtained from a trace-back postal survey. The association between pesticide use and residues was assessed using generalised linear models, controlling for potential confounding by flock location.
Procedure Between 1995 and 1997 Queensland wool clips were randomly sampled. Samples were tested for the presence and amount (mg per kg of greasy wool) of organophosphorous and synthetic pyrethroid pesticides. A questionnaire seeking information on flock characteristics and pesticide use was sent to the manager of each flock from which a wool sample was tested.
Results The median amount of OP and SP residue was 0.8 and 0.25 mg/kg, respectively, and 91 and 95% of wool samples contained < 8 mg/kg of OP and SP residues, respectively. The frequency of OP pesticide use for louse control was significantly (P = 0.005) associated with mean OP residue amount, and the timing of SP use for louse control, in relation to shearing, was significantly (P < 0.001) associated with mean SP residue amount.
Conclusion Most Queensland wool clips have acceptable amounts of residues after the use of OP and SP pesticides, but wool growers can further reduce residues by effectively controlling louse infestation with pesticide applications early after shearing and the use of non-chemical methods of ectoparasite control.  相似文献   
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The effect of an application of pST- and beta-agonists on the fattening-capacity and carcass-composition of the pig is evaluated by means of data available in literature. American stress-resistant cross-bred pigs show a stronger reaction on pST in their fattening-capacity than European breeds. Obviously, this has derived from genetic differences. Feed-utilization, meat-gain, and reduction of lipid content in the case of European breeds are, nevertheless, subject to a pronounced improvement through pST and beta-agonists. Further positive aspects are the decrease of the N-excretion in urine and no, resp. only minor influence on the quality of meat. A negative aspect of the meat with regard to consumers' acceptance is the fact that the mentioned substances belong to the group of hormones.  相似文献   
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