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941.
K L Baucus S L Ralston C F Nockels A O McKinnon E L Squires 《Journal of animal science》1990,68(2):345-351
Incidence of early embryonic death (EED) and associated changes in serum cortisol, progesterone and plasma ascorbic acid (AA) in transported mares were investigated. Mares were transported for 472 km (9 h) during either d 16 to 22 (T-3 wk, n = 15) or d 32 to 38 (T-5 wk, n = 15) of gestation. Blood samples were drawn from control, nontransported mares (NT-3 wk, NT-5 wk, n = 24) and transported mares pre-trip, midtrip, and at 0, 12, 24, 48 and 72 h post-transport and daily for the next 2 wk. Incidence of EED between transported and nontransported mares was not different (P greater than .05). Serum cortisol in all transported mares increased (P less than .05) relative to pre-trip values at midtrip and 0 h post-transport. Relative to NT mares, serum cortisol was higher (P less than .05) at midtrip in T-3 wk mares and 0 h post-transport in T-5 wk mares. Serum progesterone in all T mares increased (P less than .05) at midtrip relative to pre-trip values and was higher (P less than .05) in T-3 wk mares than in NT-3 wk mares at midtrip and 0 h post-transport. Post-transport decreases (P less than .05) in concentrations of progesterone were observed in mares that aborted. Plasma AA in transported mares increased (P less than .05) at midtrip in T-5 wk mares and decreased (P less than .05) relative to pre-trip values at 24 and 48 h post-transport (T-3 wk and T-5 wk mares, respectively).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
942.
H E Shams el Din M el Nasri 《Revue d'élevage et de médecine vétérinaire des pays tropicaux》1990,43(3):323-324
Seventeen isolates (4.27%) were recovered from 398 samples. Twelve isolates (4%) were obtained from 300 donkey nasal swabs, three (4.3%) and two (6.89%) isolates were recovered from 69 horse nasal swabs and 29 mare uterine washings, respectively. Nine isolates were lost during storage at -20 degrees C and the remaining eight were identified as mycoplasmas and their biological, biochemical and serological reactions were investigated. The isolates could be divided into two groups on the basis of glucose fermentation and arginine hydrolysis. The first group neither fermented glucose nor hydrolysed arginine. Organisms in the second group hydrolysed arginine only. 相似文献
943.
944.
Lucia T Corrêa MN Deschamps JC Bianchi I Donin MA Machado AC Meincke W Matheus JE 《Preventive veterinary medicine》2002,53(4):57-292
We evaluated stillbirth risk factors in two commercial swine farms of the Rio Grande do Sul State (south of Brazil). The study was conducted during 1 month in Farm A and during 2 months in Farm B, both during 1999. Data for all farrowings that occurred during the study period were recorded (101 for Farm A and 373 for Farm B), without interference in the farm management. In Farm A, 39% of all litters born during the period of interest had stillborn piglets and the stillborn risk for piglets was 12%. In Farm B, 25% of all litters had stillborn piglets whereas the stillborn risk was 2%. Variables considered as potential risk factors for stillbirths were: parity (1, 2–3, 4+); breed (purebred or crossbred); sow body-condition (normal or fat); use of oxytocin during parturition (yes or no); obstetric intervention through vaginal palpation (yes or no); farrowing duration (<4 or ≥4 h); mummified fetuses (yes or no); total litter size (<12 or ≥12 piglets); and litter birth weight (<11 or ≥11 kg). All stillborn piglets had their classification validated by necropsy. In multivariable logistic-regressions, the cases were the litters having at least one stillborn piglet. In Farm A, litters having at least 12 pigs and in which oxytocin was used during the parturition had 20.8-times-higher odds of stillborn occurrence. In Farm B, litters from sows having parity ≥4 had 2.2-times-higher odds of stillborn occurrence than litters from parity 2 to 3 females, litters having ≥12 pigs had 2.0-times-higher odds of a stillborn piglet than smaller litters and farrowings in which vaginal palpation was performed had 8.0-times-higher odds. Farrowing room management to minimize stillborn risk should target higher-parity females, large litters and optimization of practices of obstetric interventions. 相似文献
945.
Veeneklaas RJ Verkleij CB van Schie B Harun MA Everts ME 《Tropical animal health and production》2002,34(5):431-447
The effect of training on the potential for work in draught cattle was assessed by measuring the Na+,K+-ATPase in the muscle cell membrane and the elevation in the concentration of K+ in plasma during exercise. Biopsies of the semitendinosus muscle and venous blood samples were taken from the cattle used for draught work in Mozambique. No differences were found in the plasma ion or Na+,K+-ATPase concentrations in samples taken from Nguni, Africander and Angoni breeds. There were no significant differences in plasma ions (Na+, K+ and Cl–) or muscle Na+,K+-ATPase concentrations between the Angoni males and females, although the males showed an increase in Na+,K+-ATPase with age, while the females showed a decrease. The increase in males might be attributed to their higher level of activity in the herds than that of females. After a training period of 15 days, a significant increase in Na+,K+-ATPase concentration in semitendinosus muscle was found in Angoni cattle. In females, this was significant after 8 days of training (about 30%); in males after 15 days of training (about 16%). On day 15, there was a reduction in the elevation of plasma K+ during the 2 h of draught work, indicating an increased capacity of the Na+,K+ pumps to maintain the extracellular K+ concentration in working muscles and a possible delay in the moment of fatigue. 相似文献
946.
Toribio RE Kohn CW Chew DJ Capen CC Rosol TJ 《American journal of veterinary research》2002,63(2):194-197
OBJECTIVES: To clone and sequence the cDNA for feline preproparathyroid hormone (preproPTH) and to compare that sequence with other known parathyroid hormone (PTH) sequences. SAMPLE POPULATION: Parathyroid glands from 1 healthy cat. PROCEDURES: A cDNA library was constructed in lambda phage from feline parathyroid gland mRNA and screened with a radiolabeled canine PTH probe. Positive clones were sequenced, and nucleic acid and deduced amino acid sequences were analyzed and compared with known preproPTH and PTH sequences. RESULTS: Screening of approximately 2 X 10(5) recombinant plaques revealed 3 that hybridized with the canine PTH probe; 2 clones comprised the complete sequence for feline preproPTH. Feline preproPTH cDNA consisted of a 63-base pair (bp) 5'-untranslated region (UTR), a 348-bp coding region, and a 326-bp 3'-UTR. The coding region encoded a 115-amino acid peptide. Mature feline PTH consisted of 84 amino acids. Amino acid sequence analysis revealed that feline PTH was > 83% identical to canine, bovine, swine, equine, human, and macaque PTH and 69, 71, and 44% identical to mouse, rat, and chicken PTH, respectively. Within the region responsible for hormonal activity (amino acids 1 to 34), feline PTH was > 79% identical to other mammalian PTH sequences and 64% identical to the chicken sequence. CONCLUSIONS AND CLINICAL RELEVANCE: The amino acid sequence of PTH is conserved among mammalian species. Knowledge of the cDNA sequence for feline PTH may be useful to investigate disturbances of calcium metabolism and alterations in PTH expression in cats. 相似文献
947.
948.
949.
Barbour E.K. Bouljihad M. Hamdar B. Sakr W. Eid A. Safieh-Garabedian B. 《Veterinary research communications》1999,23(3):191-200
The dynamics of the serum concentration of protein 27 (P27) of avian leukosis virus and transforming growth factor 2 (TGF-2) were compared during the period between 29 and 59 weeks of age in two flocks of broiler chicken breeding stock undergoing outbreaks of severe lymphoid leukosis (LL) associated with persistent high mortality (susceptible) and in another two flocks of breeding stock with the presence of avian leukosis virus in association with low mortality due to LL (resistant). The average mean concentration of serum P27 in the LL-susceptible flocks was significantly higher (<0.05) than that in the LL-resistant flocks in six out of seven samplings performed at 5-week intervals, between 29 and 59 weeks of age. The peak in the average rise of serum P27 in the LL-resistant flocks (309 pg/ml) was associated with the highest level of TGF-2 (1282 pg/ml) among all flocks and at all sampling times. The significance of TGF-2 in inhibition of lymphoid tumour development is discussed. 相似文献
950.
Morita T Shimada A Ohama E Umemura T Fukuda S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1999,61(2):107-111
We performed a pathologic examination of the brains of three dogs in an epileptic beagle colony. Histologically, all the cases had diffuse astrocytosis in the cerebral cortex and basal ganglia as well as the hippocampus, whereas they showed acute nerve cell change in the hippocampus and some other areas of the cerebrum. One of these animals showed laminar myelin pallor associated with the presence of many vacuoles in the IV to VI layers of the bilateral motor cortices. Most of the vacuoles contained fine granules stained with luxol-fast-blue stain. Ultrastructural examination revealed that some oligodendrocytes and perineuronal satellite oligodendrocytes in the bilateral cerebral motor cortices of the two affected dogs had many vacuoles surrounded by myelin-like lamellar structures. These findings suggest a possibility that astrocytosis in the cerebrum and vacuolar degeneration of oligodendrocytes in the cerebral motor cortex may be, at least in part, related to the occurrence or development of seizures. 相似文献