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991.
Between September 1982 and March 1984, 101 Western Australian piggeries with 15 or more sows were surveyed to determine the prevalence of internal parasites and examine the relationship between parasitism and management practices. Faecal samples were collected from 20 pigs in 4 age groups in randomly selected piggeries, and examined for the presence of eggs of helminth parasites and protozoan cysts. Evidence of nematode parasites was found in 79% of piggeries. Sows were more commonly affected than other classes of pigs with worm eggs being found in 68% of herds. Oesophagostomum spp was the most prevalent worm species, being found in pigs from 65% of piggeries and in sows in 60% of herds. Ascaris suum was the most common species of worm found in growing pigs. There was no evidence of infection with either Metastrongylus spp or Strongyloides spp in any of the herds sampled. Oocysts of coccidia were found in pigs from 56% of piggeries and Balantidium coli cysts were detected in pigs from 42% of piggeries sampled. 相似文献
992.
The induction of endometrial prostaglandin (PG) F2 synthesis by oxytocin is dependent upon activation of phospholipase (PL) A2 and mobilization of arachidonic acid. The objective of this study was to determine if oxytocin stimulates PGF2 synthesis by inducing synthesis of cytosolic PLA2 (cPLA2). In Experiment 1, 15 ovariectomized ewes were given progesterone and estradiol to simulate an estrous cycle. Ewes were then given an injection of oxytocin on Day 14 of the simulated estrous cycle. Jugular blood samples were collected and assayed for 13,14-dihydro-15-keto-prostaglandin F2 (PGFM). Uteri were collected at 0, 7.5, 25, 90, or 240 min postinjection (n = 3 ewes/time point). Total RNA was isolated from caruncular endometrium and subjected to dot-blot analysis. Oxytocin induced a rapid and transient increase in serum PGFM (P < 0.01). However, endometrial concentrations of cPLA2 mRNA did not change following oxytocin administration (P > 0.10). In Experiment 2, 11 ovary-intact ewes were given oxytocin (n = 5) or saline (n = 6) on Day 15 after estrus. Jugular blood samples were collected and assayed for serum concentrations of PGFM. Uteri were collected at 15 min postinjection. Homogenates were prepared from caruncular endometrium and subjected to Western blot analysis. Concentrations of PGFM were higher in oxytocin treated ewes compared to saline treated ewes at 15 min postinjection (P < 0.01). Endometrial concentrations of cPLA2 protein were greater in the cytosolic than in the microsomal fraction (P < 0.01). Oxytocin did not affect the amount of cPLA2 protein in either fraction (P > 0.10). In conclusion, oxytocin did not effect expression of either cPLA2 mRNA or protein in ovine endometrium. Oxytocin may stimulate PGF2 synthesis by activating cPLA2 protein that is already present in an inactive form. 相似文献
993.
David E Kenny Michael R Lappin Felicia Knightly Jeffery Baler Melissa Brewer David M Getzy 《Journal of zoo and wildlife medicine》2002,33(2):131-138
In May 1996 the Denver Zoological Gardens obtained two male and two female Pallas' cats (Otocolobus felis manul) that were wild-caught in the Ukraine. These animals were part of a group of 16 wild-caught adults (eight male and eight female) imported to the United States and Canada between 1995 and 1996. The Denver Zoological Gardens cats were quarantined at the zoo hospital for approximately I mo. During the quarantine period they were immobilized for physical examination, and sera were obtained from them to evaluate for exposure to Toxoplasma gondii. All cats were positive for T. gondii antibodies by latex agglutination (titers from 1:512 to 1:1,024). After being paired for breeding, one pair produced two litters, and another pair produced four litters, a total of 17 kittens between 1997 and 2001. Four kittens and two young adults died from a disseminated granulomatous and necrotizing inflammation consistent with toxoplasmosis. Toxoplasma gondii infection was confirmed in all six deceased cats by polymerase chain reaction performed on formalin-fixed tissues. An additional five kittens disappeared and were not available for necropsy. The fatality rate from toxoplasmosis was 35.3% (6/17) for cats that were available for necropsy and could have been as high as 64.7% (11/17) if it were assumed that the disappeared kittens were also affected. The Pallas' kitten survival rate at the Denver Zoological Gardens was 35.3%. This article describes the clinical and pathologic features of toxoplasmosis in a group of Pallas' cats at the Denver Zoological Gardens. 相似文献
994.
Thirty-two boars were fed diets containing 0, 3, 6 or 9 ppm zearalenone from 32 d of age up to 145 or 312 d of age. Rate of gain, feed intake and gain:feed were not significantly different among treatments. Feeding of diets containing 9 ppm zearalenone did not affect the libido in seven boars. There was a tendency for boars fed 9 ppm dietary zearalenone to produce lower total and gel free volumes of semen, with lower total motile sperm; however, only the percent motility of the sperm was reduced (P less than .05). 相似文献
995.
Relationship between level of forage intake,blood flow and oxygen consumption by splanchnic tissues of sheep fed a tropical grass forage 下载免费PDF全文
F. Hentz G. V. Kozloski D. Zeni M. V. Brun S. Stefanello 《Journal of animal physiology and animal nutrition》2017,101(1):121-126
Four Polwarth castrated male sheep (42 ± 4.4 kg live weight (LW) surgically implanted with chronic indwelling catheters into the mesenteric, portal and hepatic veins, housed in metabolism cages and offered Cynodon sp. hay at rates (g of dry matter (DM)/kg LW) of 7, 14, 21 or ad libitum, were used in a 4 × 4 Latin square experiment to evaluate the effect of the level of forage intake on blood flow and oxygen consumption by the portal‐drained viscera (PDV), liver and total splanchnic tissues (ST). The portal blood flow and the oxygen consumption by PDV linearly increased at increased organic matter (OM) intake. No effect of level of OM intake was obtained for the hepatic artery blood flow and oxygen consumption by liver. As a consequence, the level of OM intake only tended to directly affect hepatic blood flow and oxygen consumption by total ST. Oxygen consumption was linearly and positively related to blood flow across PDV, liver and total ST. The heat production by PDV and total ST, as proportion of metabolizable energy (ME) intake, decreased curvilinearly at increased ME intake. In conclusion, the oxygen consumption by PDV, but not by liver, was directly related to the level of forage intake by sheep. Moreover, when ingested at levels below maintenance, most of ME was spent as heat produced by ST. 相似文献
996.
Disposition of the anti‐ulcer medications ranitidine,cimetidine, and omeprazole following administration of multiple doses to exercised Thoroughbred horses 下载免费PDF全文
H. K. Knych S. D. Stanley R. M. Arthur D. S. McKemie 《Journal of veterinary pharmacology and therapeutics》2017,40(1):92-96
The use of anti‐ulcer medications, such as cimetidine, ranitidine, and omeprazole, is common in performance horses. The use of these drugs is regulated in performance horses, and as such a withdrawal time is necessary prior to competition to avoid a medication violation. To the authors' knowledge, there are no reports in the literature describing repeated oral administrations of these drugs in the horse to determine a regulatory threshold and related withdrawal time recommendations. Therefore, the objective of the current study was to describe the disposition and elimination pharmacokinetics of these anti‐ulcer medications following oral administration to provide data upon which appropriate regulatory recommendations can be established. Nine exercised Thoroughbred horses were administered 20 mg/kg BID of cimetidine or 8 mg/kg BID of ranitidine, both for seven doses or 2.28 g of omeprazole SID for four doses. Blood samples were collected, serum drug concentrations were determined, and elimination pharmacokinetic parameters were calculated. The serum elimination half‐life was 7.05 ± 1.02, 7.43 ± 0.851 and 3.94 ± 1.04 h for cimetidine, ranitidine, and omeprazole, respectively. Serum cimetidine and ranitidine concentrations were above the LOQ and omeprazole and omeprazole sulfide below the LOQ in all horses studied upon termination of sample collection. 相似文献
997.
The tallgrass prairie of North America has undergone widespread habitat loss and fragmentation (<4% remains). The Flint Hills
region of Kansas and Oklahoma is the largest tallgrass prairie remaining and therefore provides an opportunity to study the
population genetic structure of grassland species in a relatively contiguous landscape and set a baseline for evaluating changes
when the habitat is fragmented. We adopted a landscape genetics approach to identify how landscape structure affected dispersal,
population genetic structure, and landscape connectivity of the Eastern Yellowbelly Racer (Coluber constrictor flaviventris) across a 13,500-km2 landscape in northeastern Kansas, USA. The racer population had high allelic diversity, high heterozygosity, and was maintaining
migration-drift equilibrium. Autocorrelation between genetic and geographic distance revealed that racers exhibited restricted
dispersal within 3 km, and isolation-by-distance. Significant isolation-by-distance occurred at broad regional scales (>100 km),
but because of sufficient gene flow between locations, we were unable to define discrete subpopulations using Bayesian clustering
analyses. Resistance distance, which considers the permeability of habitats, did not explain significant variation in genetic
distance beyond Euclidean distance alone, suggesting that racers are not currently influenced by landscape composition. In
northeastern Kansas, racers appear to be an abundant and continuously distributed snake that perceives the landscape as well
connected with no cover type currently impeding snake dispersal or gene flow. 相似文献
998.
Interaction of chlorhexidine with trisEDTA or miconazole in vitro against canine meticillin‐resistant and ‐susceptible Staphylococcus pseudintermedius isolates from two UK regions 下载免费PDF全文
999.
Investigations were conducted during the 2003, 2004 and 2005 growing seasons in northern Greece to evaluate effects of tillage regime (mouldboard plough, chisel plough and rotary tiller), cropping sequence (continuous cotton, cotton–sugar beet rotation and continuous tobacco) and herbicide treatment on weed seedbank dynamics. Amaranthus spp. and Portulaca oleracea were the most abundant species, ranging from 76% to 89% of total weed seeds found in 0–15 and 15–30 cm soil depths during the 3 years. With the mouldboard plough, 48% and 52% of the weed seedbank was found in the 0–15 and 15–30 cm soil horizons, while approximately 60% was concentrated in the upper 15 cm soil horizon for chisel plough and rotary tillage. Mouldboard ploughing significantly buried more Echinochloa crus‐galli seeds in the 15–30 cm soil horizon compared with the other tillage regimes. Total seedbank (0–30 cm) of P. oleracea was significantly reduced in cotton–sugar beet rotation compared with cotton and tobacco monocultures, while the opposite occurred for E. crus‐galli. Total seed densities of most annual broad‐leaved weed species (Amaranthus spp., P. oleracea, Solanum nigrum) and E. crus‐galli were lower in herbicide treated than in untreated plots. The results suggest that in light textured soils, conventional tillage with herbicide use gradually reduces seed density of small seeded weed species in the top 15 cm over several years. In contrast, crop rotation with the early established sugar beet favours spring‐germinating grass weed species, but also prevents establishment of summer‐germinating weed species by the early developing crop canopy. 相似文献
1000.
K. G. Haughey B.V.Sc. 《Australian veterinary journal》1975,51(1):22-27
Thirty Angus, Hereford and Shorthorn term calves dying before, during or within 7 days of birth in a large beef herd were autopsied. Selected specimens were examined histologically. Two carcasses were classified in the category of ante-parturient death, 24 as parturient, and 4 were classified in the post-parturient death category. Three of the latter showed evidence of starvation. Eight of the calves in the parturient death category were assisted during delivery, and 16 were not assisted. The incidence of nulliparous dams among assisted parturient deaths was significantly higher than among the unassisted group. A high incidence of meningeal haemorrhages and congestion were observed at single or multiple sites, within and around the cranial and spinal meninges. The lesions comprised subdural and epidural haemorrhages, bloodstained cerebrospinal fluid and leptomeningeal haemorrhage and congestion. They were seen in calves in both parturient and post-parturient death categories but not in the ante-parturient group. All calves classified in the parturient death category which were assisted during delivery showed haemorrhages involving the cranial and/or spinal meninges. Additional birth injuries, including separation of the costo-chondral junctions, fractured ribs, haemorrhage into the hip joints, inter-vertebral fibrocartilages and axillae, and rupture of the liver, were frequently present. Ten of the calves in the parturient death category which were unassisted during delivery showed meningeal haemorrhage and congestion. Two of the 4 calves in the post-parturient death category showed similar lesions and both showed evidence of starvation. The meningeal haemorrhages and congestion were similar to those observed in perinatal lamb mortality. They are considered manifestations of injury to the CNS arising from trauma and/or hypoxia during birth. Gross or microscopic evidence of infection was present in 2 calves in the post-parturient death category. Calves which had starved showed subcutaneous oedema of the distal limbs, congestion and focal haemorrhage of the adrenal cortex and red-brown fat depots. It is suggested that these changes are evidence of cold injury, and that fat in newborn calves responds to cold and starvation in a manner similar to the brown fat of newborn lambs. 相似文献