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To examine the effects of exogenous porcine (p) ST on measures of stress and immune function in weaned pigs with or without transport, pigs (20 +/- 1 d of age) received daily injections of pST (0.5 mg/kg; n = 16) or saline (n = 16) for 5 d. On d 5, a blood sample was collected immediately before injection. At 4 h postinjection, pigs were weighed, sampled for blood, injected with di-nitrophenyl-conjugated keyhole limpet hemocyanin, and weaned. One half of the pigs in each group were transported for 3 h before placement in the nursery. Pigs were weighed, and blood was collected on 1, 7, and 14 d postweaning. Statistical significance was set at P < 0.05. Serum IGF-I concentrations were increased by pST and decreased by weaning, but not affected by transport. The free cortisol index was elevated in all pigs 1 d postweaning, although less in transported versus nontransported pigs. By 7 d postweaning, the free cortisol index returned to prewean values. Serum concentrations of immunoglobulin (Ig) G increased in all pigs by 14 d postweaning, but were not affected by pST or transport. Serum IgM concentrations were elevated at 7 and 14 d postweaning. Before weaning and again 1 d postweaning, pigs treated with pST had greater concentrations of IgM than did control animals. Circulating neutrophils increased in pST-treated pigs 4 h after the final pST injection. Improved immune function in weaned pigs by pST may lead to greater health and growth in a commercial setting.  相似文献   
175.
1. Naked oats belong to the same species as 'common oats', Avena sativa, but have a non-lignified husk which readily becomes detached during harvesting. The absence of the indigestible husk can be predicted to give an increased metabolisable energy (ME) content for poultry. 2. Measurements of true metabolisable energy (TME(N)) were performed on 3-week-old broiler chicks (Cobb males), adult cockerels (ISA Brown, greater than one year old) and 7-week-old turkeys (BUT T8 males). The measurements were repeated in 2000, 2001 and 2002, with some measurements on a subset of varieties in 2004. 3. High-oil naked oat lines yielded 12% more energy (TME(N)) than wheat. Naked oats, excluding the experimental high-oil lines, yielded 8.5% more energy than simultaneously assayed wheat samples. 4. In samples from the 2004 harvest, conventional oats gave TME(N) values about 13% lower than those of wheat. 5. The addition of beta-glucanase produced an increase of about 4% in the apparent metabolisable energy (AME) of oats for broiler chickens. This effect was associated with a 70% decrease in the jejunal viscosity of broilers receiving a 500 g/kg naked-oat diet. 6. The oil content of naked oats was about 5 times greater than that of wheat, with the high-oil lines rising to more than 6 times greater. Naked oats had a lower starch content than wheat but not sufficiently lower to negate the energy benefits of the higher oil content. The crude protein (CP) contents of naked oats were similar to those of wheat, with the high-oil varieties tending to be higher in CP also.  相似文献   
176.
Prevalence of dental disorders in 483 horses and ponies Five equine veterinarians working at three equine referral hospitals examined the oral cavity of 483 horses and ponies prior to surgery, to gain information about the prevalence of common dental disorders in the horse. A thorough examination, using hands/fingers, a full-mouth speculum, a dental mirror and a good light source, is essential to detect such disorders. Many horses examined needed dental attention even though there were no problems with mastication or riding. The most detected abnormalities were sharp enamel points on the buccal side of the upper arcade and the lingual side of the lower arcade, and hooks at 106/206 and 311/411. Regular dental care would improve the condition and welfare of horses.  相似文献   
177.
The aim of the study was to evaluate and compare the effects of caudal epidural administration of meperidine (MP), lidocaine (LD), and a combination of the two (MPLD) in six mature saddle horses. Horses were randomly assigned to receive three treatments (MP 0.3 mg/kg; LD 0.2 mg/kg; and MPLD: MP 0.3 mg/kg and LD 0.2 mg/kg), with at least 1 week between treatments. Drugs were injected into the epidural space between the first and second coccygeal areas in conscious standing horses. Analgesia, ataxia, sedation, cardiovascular and respiratory effects, and rectal temperature were recorded at different intervals before (baseline) and after administration. Epidural administration of MPLD resulted in a longer duration of analgesia of the tail, perineum, and upper hind limb regions than did administration of MP or LD alone.  相似文献   
178.
Human athletes taper or reduce their training load before a race to enhance performance, apparently because recovery from the effects of fatigue occurs faster than the loss of fitness from the reduced training. However, there appear to be no previous studies of tapering of equine athletes. Our aim in the present study was, therefore, to investigate the efficacy of tapering with Standardbred pacers. We determined the effect of repeated cycles of tapered training on performance of Standardbred pacers. After 8 weeks of jogging and 3 x 2 week cycles of pace work, 19 horses were randomised to a taper and a control group. The taper group completed 5 consecutive 2 week cycles, each incorporating a 7 day taper; some cycles included high-intensity interval training. The control group continued with 5 more cycles of pace work. All horses completed a 2400 m individual time trial after each cycle. Peak and mean speed of the taper group were faster than those of the control group in all cycles; the differences were clear-cut in all cycles for peak speed (overall 4.4%, 95% confidence interval 1.7 to 7.1%), but only in one of the interval-training cycles for mean speed (2.4%, 0.3 to 4.7%). Four horses in the taper group were injured during interval training. Repeated tapering produces a worthwhile enhancement of performance in Standardbreds, but the addition of interval training appears to increase the risk of injury.  相似文献   
179.
The morphology of Onchocerca lupi, responsible for canine ocular onchocercosis, is unique within the genus. Earlier analyses of the 5S ribosomal RNA gene spacer region sequence of the parasite and the 16S ribosomal RNA gene sequence of its Wolbachia endosymbiotic bacteria (Rickettsiales) supported the morphological and biological arguments that O. lupi is a distinct species. However, the exact phylogenetic position of O. lupi and its endosymbiont could not be unambiguously determined. Herein we report analyses based on the mitochondrial cytochrome oxidase I (COI) gene of the filarial species and the Wolbachia surface protein (wsp) and the bacterial cell-cycle ftsZ genes of their wolbachiae. Our results indicate that O. lupi separated from other Onchocerca spp. early in evolution. This is in line with the previous morphological analysis demonstrating that O. lupi is an atypical Onchocerca species showing both primitive and evolved characters. The phylogenetic trees generated for the COI sequences of filariae and the wsp and ftsZ sequences of their wolbachiae were congruent with each other, which supports the hypothesis that nematodes and their Wolbachia endobacteria share a long co-evolutionary history.  相似文献   
180.
A live attenuated Mycoplasma gallisepticum vaccine, ts-11, has been used for control of M gallisepticum in several countries. The rapid serum agglutination test is usually used as an indicator of flock response to vaccination; however, in some flocks, the detected response may be weak or absent. We investigated whether the low level, or lack, of systemic antibodies in ts-11-vaccinated flocks is correlated with susceptibility to infection after challenge with a virulent M. gallisepticum strain. Birds from 2 separate ts-11-vaccinated commercial flocks with no, or weak, rapid serum agglutination responses (at 11 or 14 wk postvaccination) were randomly selected and subjected to aerosol challenge with either M gallisepticum strain Ap3AS or sterile mycoplasma broth. A group of nonvaccinated specific-pathogen-free chickens at similar age were also exposed to aerosolization with M. gallisepticum strain Ap3AS and used as positive controls. Postmortem examination of the birds, performed 2 wk after challenge, revealed no significant difference in microscopic tracheal lesions or mucosal thicknesses between the ts-11-vaccinated field birds irrespective of their aerosolization treatment. However, both microscopic tracheal lesions and tracheal mucosal thicknesses of nonvaccinated challenged birds were significantly greater than those of ts-11 vaccinates. Hence, broiler breeders vaccinated in the field showed significant protection against virulent M. gallisepticum challenge even when no serum antibody was detected by rapid serum agglutination test. These results reveal that seroconversion detected by rapid serum agglutination test after ts-11 vaccination is not a reliable predictor of protection against M. gallisepticum infection. The possible significance of local antibody response and cell-mediated immunity against M. gallisepticum infection is discussed.  相似文献   
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