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71.
72.
Objective To investigate the seroprevalence of equine herpesvirus 1 in foals around weaning and after weaning on two large Thoroughbred farms using a type-specific enzyme-linked immunosorbent assay to determine exposure to infection.
Design A longitudinal population study in groups of Thoroughbred weanling foals.
Study population Two hundred weanling Thoroughbred foals from a population of about 380 foals were enrolled on two adjacent stud farms in the Hunter Valley of New South Wales. Foals on both farms were weaned from February to May 1995 into randomly selected groups of 10 to 15 foals. Farms were selected because of their willingness to cooperate in the survey and because their detailed records of foals and their movements. They were representative of well-managed large Thoroughbred stud farms in New South Wales. Both studs had upper respiratory tract disease among weanling foals around weaning each year although the sero-prevalence of viral respiratory disease on either farm was not known before the study.
Procedure Serum was collected from foals within each group at fortnightly intervals from 9th February until 1st June 1995, and at a single follow-up period in August 1995. Each sample was tested in triplicate using an antibody-detection ELISA which is type-specific for EHV-1 and EHV-4 antibodies.
Results and conclusions There was serological evidence of EHV-1 infection both before and after weaning. The prevalence of EHV-1 antibody in the sample population increased during the study and individual cases of EHV-1 infection were identified. The increase was caused both by the seroconversion of foals within the groups and by the recruitment into the study of foals with pre-existing EHV-1 antibody. Evidence of EHV-1 infection in Thoroughbred foals after weaning has not been reported previously in Australia and this has implications for vaccination regimens.  相似文献   
73.
Antioxidants have been widely used during in vitro production to decrease the negative effect of reactive oxygen species. It was reported that the complex resveratrol–methyl β‐cyclodextrin (RV ‐CD ) improves resveratrol's stability and bioavailability and increases its antioxidant activity. This study evaluates the effect of RV ‐CD during in vitro oocyte maturation (IVM ) or in vitro embryo culture (IVC ) on developmental competence and quantitative changes in gene expression of developmental important genes. In experiment 1, RV ‐CD was added to IVM media and maturation level, embryo development and oocytes, cumulus cells, and blastocysts gene expression by RT ‐qPCR were examined. In experiment 2, presumptive zygotes were cultured in SOF supplemented with RV ‐CD and embryo development and blastocysts gene expression by RT ‐qPCR were studied. A group without RV ‐CD (control?) and a group with cyclodextrin (control+) were included. No differences were found in cleavage rate or blastocyst yield between groups. However, the expression of LIPE was higher in blastocysts derived from oocytes treated with resveratrol compared with control groups (<  .05). Blastocysts produced by IVC with resveratrol showed that RV ‐CD could modify the expression of genes related to lipid metabolism (CYP 51A1 , PNPLA 2 and MTORC 1 ) compared with control groups (p  < .05). RV ‐CD in the IVM and IVC media could reduce accumulated fat by increasing lipolysis and suppressing lipogenesis of blastocysts.  相似文献   
74.
The objectives of this study were to determine (i) if in subtropical goats that gave birth during mid‐December, the exposition to an artificial long‐day photoperiod consisting in only 14 hr of light per day can increase the milk yield and (ii) to test whether these females can respond to the male effect at the end of the prolonged photoperiodic treatment. In experiment 1, 17 lactating goats were maintained under natural short days (control group), while another 22 goats were maintained under artificial long days (treated group) consisting in 14 hr light and 10 hr darkness starting at day 10 of lactation. The continuous exposition to an artificial long‐day photoperiod produced an increase in the milk yield level during the first 110 days of lactation (time × treatment interaction; = .01), while none of the milk components were modified due to the photoperiodic treatment (> .05). In experiment 2, all control and treated anovulatory goats were submitted to the male effect using photostimulated males. All females showed oestrous behaviour within the first 10 days that were in contact with males (100% in both groups; > .05). Thus, the latency to onset of oestrus did not differ between females from control (58.2 ± 3.0 hr) and treated (62 ± 4.6 hr) groups. Male exposition provoked ovulation independently if females were previously under long days or natural photoperiod (96 vs 100%, respectively; = .79). It was concluded that exposure to 14 hr of light per day in subtropical goats that gave birth in late autumn stimulates milk yield without preventing the ovulation in response to the male effect at the end of the prolonged photoperiodic treatment.  相似文献   
75.
AIMS: To investigate the use and utility of collars for companion cats in New Zealand, and to explore public perception of collar use.

METHODS: An online questionnaire was distributed using emails and social media to members of the general public in New Zealand. The questionnaire collected details of respondents, cat ownership status, and responses to a number of questions regarding collar use in cats.

RESULTS: A total of 511 responses were collected. Of these, 393/511 (76.9%) reported owning ≥1 cat at the time of the survey, and 141/393 (35.9%) stated that ≥1 of their cats wore collars and 211/393 (53.7%) had ≥1 of their cats micro-chipped. Of the respondents with a pet cat, 351/393 (89.3%) allowed their cats some outdoor access. Respondents mainly used collars for identification and to reduce predation. Reasons for not using collars included cat intolerance of collars, repeated collar loss and concern over collar safety. Differences were found between cat owners and non-owners regarding whether they agreed that cats were important for pest control (43 vs. 25%, p<0.001); that not all cats will tolerate collars (81 vs. 64%, p<0.001); that cats should be kept indoors at night (37 vs. 58%, p<0.001); or disagreed that well fed cats will not catch birds (60 vs. 70%, p=0.04); and disagreed that a cat without a collar was likely to be a stray (85 vs. 76%, p<0.001). Respondents most trusted veterinarians and the Society for the Prevention of Cruelty to Animals as sources of pet care information.

CONCLUSIONS: Collar use within this sample of cat owners in New Zealand appeared to be low, with more using microchips for identification. The majority of cat owners in this study indicated their cats had some outdoor access, with collars being used for cat identification and to reduce hunting behaviour. Significant differences existed in opinions on cat management between cat owners and non-owners in this study. It should be noted that this preliminary exploration was based on a self-selected group of respondents and so results and conclusions cannot be extrapolated to the wider population.

RELEVANCE: As the most trusted source of information about pet care, an enhanced understanding of cat ownership and management may be of use to veterinarians to promote responsible pet ownership and to develop national policies and practices to improve cat welfare.  相似文献   

76.
Splenic lymphoma in a short-beaked echidna (Tachyglossus aculeatus)   总被引:1,自引:1,他引:0  
A 23-year-old, male short-beaked echidna ( Tachyglossus aculeatus ) housed at a North American zoo was successfully treated for flea-associated anaemia, but subsequently died. Cause of death was presumptive septicaemia secondary to splenic lymphoma. This is only the fifth case of neoplasia reported in this monotreme species, and the first from outside of Australia.  相似文献   
77.
Objective  To establish reference values for activated coagulation time (ACT) in normal cats and dogs, by visual assessment of clot formation using the MAX-ACTTM tube.
Subjects  We recruited 43 cats and 50 dogs for the study; 11 cats and 4 dogs were excluded from the statistical analysis because of abnormalities on clinical examination or laboratory testing including anaemia, prolonged prothrombin time (PT) or activated partial thromboplastin time (APTT), or insufficient plasma volume for comprehensive laboratory coagulation testing.
Procedure  Blood samples were collected via direct venipuncture for MAX-ACT, packed cell volume/total solids, manual platelet estimation and PT/APTT measurement. Blood (0.5 mL) was mixed gently in the MAX-ACT tube at 37°C for 30 s, then assessed for clot formation every 5 to 10 s by tipping the tube gently on its side and monitoring for magnet movement. The endpoint was defined as the magnet lodging in the clot. The technique was tested with 10 dogs by collecting two blood samples from the same needle insertion and running a MAX-ACT on each simultaneously.
Results  In normal cats the mean MAX-ACT was 66 s (range 55–85 s). In normal dogs the mean was 71 s (range 55–80 s). There was no statistical difference between the first and second samples collected from the same needle insertion.
Conclusions and Clinical Relevance  In both cats and dogs, a MAX-ACT result >85 s should be considered abnormal and further coagulation testing should be performed. Additionally, failure to discard the first few drops of the sample does not appear to significantly affect results.  相似文献   
78.
79.
OBJECTIVE: To develop rapid (< 8 hour) tests using polymerase chain reaction (PCR) for the diagnosis of equine herpesvirus 3 (EHV3; equine coital exanthema virus), equine gammaherpesviruses 2 (EHV2) and EHV5, equine adenovirus 1 (EAdV1), EAdV2, equine arteritis virus (EAV), equine rhinitis A virus (ERAV; formerly equine rhinovirus 1) DESIGN: Either single round or second round (seminested) PCRs were developed and validated. METHODS: Oligonucleotide primers were designed that were specific for each virus, PCR conditions were defined and the specificity and sensitivity of the assays were determined. The application of the tests was validated using a number of independent virus isolates for most of the viruses studied. The PCRs were applied directly to clinical samples where samples were available. RESULTS: We developed a single round PCR for the diagnosis of EHV3, a seminested PCR for EHV2 and single round PCRs for EHV5, EAdV1, EAdV2 and RT-PCRs for EAV and ERAV. The PCR primer sets for each virus were designed and shown to be highly specific (did not amplify any recognised non-target template) and sensitive (detection of minimal amounts of virus) and, where multiple virus isolates were available all isolates were detected. CONCLUSION: The development and validation of a comprehensive panel of PCR diagnostic tests, predominantly for viruses causing equine respiratory disease, that can be completed within 8 hours from receipt of clinical samples, provides a major advance in the rapid diagnosis or exclusion diagnosis of these endemic equine virus diseases in Australia.  相似文献   
80.
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