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61.
62.
Two vaccines, based on formalin-killed whole cells of toxigenic Pasteurella multocida type D and Bordetella bronchiseptica combined with a partially toxoided cell extract of P multocida, were prepared with Freund's incomplete adjuvant (vaccine 1) or by alum precipitation (vaccine 2). Each was tested for safety and efficacy in reducing the severity of nasal turbinate atrophy and improving the growth rate of pigs in three Western Australian commercial piggeries with endemic atrophic rhinitis. In safety experiments with vaccine 1, no adverse clinical effects were observed in vaccinated sows or their progeny. Piglets receiving vaccine 2 showed no injection site abnormalities, pyrexia or turbinate atrophy. In field trials, vaccine 1 significantly reduced the prevalence of moderate to severe nasal turbinate atrophy (Done score 3 to 5) when used in two piggeries (A and B). Progeny from vaccinated sows in piggery B also grew significantly faster than controls. When vaccine 2 was used in piggery A at a later date and in another piggery (C), growth rate was not improved in either piggery and the prevalence of moderate to severe turbinate atrophy was reduced only in piggery C.  相似文献   
63.
Data from the Global Oscillation Network Group (GONG) project and other helioseismic experiments provide a test for models of stellar interiors and for the thermodynamic and radiative properties, on which the models depend, of matter under the extreme conditions found in the sun. Current models are in agreement with the helioseismic inferences, which suggests, for example, that the disagreement between the predicted and observed fluxes of neutrinos from the sun is not caused by errors in the models. However, the GONG data reveal subtle errors in the models, such as an excess in sound speed just beneath the convection zone. These discrepancies indicate effects that have so far not been correctly accounted for; for example, it is plausible that the sound-speed differences reflect weak mixing in stellar interiors, of potential importance to the overall evolution of stars and ultimately to estimates of the age of the galaxy based on stellar evolution calculations.  相似文献   
64.
There are few reports of coagulation times in marsupial species. Blood samples collected from 14 Bennett's wallabies (Macropus rufogriseus) under anaesthesia during routine health assessments were analysed for prothrombin time (PT) and activated partial thromboplastin time (aPTT) using a point‐of‐care analyser (POC) (Abaxis VSPro®). The wallabies had an aPTT mean of 78.09 s and median of 78.1 s. The PT for all wallabies was greater than 35 s, exceeding the longest time measured on the POC. Although PT was significantly longer, aPTT was similar to the manufacturer's domestic canine reference range.  相似文献   
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Objectives of this study were to characterize patterns of follicular development in sheep superovulated with purified follicle stimulating hormone (FSH) (OVAGENTM, ICP, Auckland, New Zealand) and to determine its influence on preovulatory events (onset of the oestrus behaviour and timing of the preovulatory luteinizing hormone surge) and ovarian response (ovulation rate and embryo yield). Number and size of all ≥ 23 mm follicles from the first FSH injection to withdrawal of progestagen sponges was determined by transrectal ultrasonography just prior to every FSH injection in nine Manchega ewes superovulated with eight decreasing doses (ml) (1.5 × 3, 1.25 × 2 and 1 × 3) of OVAGEN injected twice daily from 60 h before to 24 h after the withdrawal of 40 mg fluorogestone acetate sponges. Oestrous detection and jugular blood sampling for LH radioimmunoassay were performed every 3 h from 14 to 53 h after sponge removal and ovulation rate and number of embryos were determined 4 days after progestagen withdrawal. Administration of OVAGEN induced a significant rise (p < 0.0005) in the number of follicles ≥ 4 mm in size because of an increased growth in size of follicles from the first FSH injection to sponge removal, an increase in the number of newly detected follicles from 12 to 36 h of the first FSH dose (p < 0.005) and a decrease in regression rate from 24 h (p < 0.001). The number of follicles 2–3 mm in size at first FSH dose (10.4 ± 1.5) was positively correlated with the number of ≥ 4 mm follicles at 0 h (19.0 ± 2.7, p < 0.01). A higher number of ≥ 4 mm follicles at 0 h was related with an earlier appearance of oestrus (31.5 ± 1.5 h, p = 0.08) and LH surge (45.0 ± 2.3 h, p < 0.005), and a higher ovulation rate (18.2 ± 3.8, p < 0.005). On the other hand, the rate of embryo recovery was decreased in ewes with earlier preovulatory LH peaks (p < 0.005), with a shorter interval between oestrus and LH peak (p < 0.05).  相似文献   
67.
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   
68.
69.
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   
70.
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   
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