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991.
This study examined the effect of number of conceptuses on maternal concentrations and profiles of estrogen sulfate, estrone, estradiol-17 beta, progesterone and prolactin in gilts. Estradiol-valerate injections were used to induce pseudopregnancy (O conceptuses; n = 5) and oviduct ligation or no treatment were utilized to obtain pregnant gilts with 4 to 7 (n = 4), or 8 to 11 (n = 4) conceptuses, respectively. Blood samples were collected every 10 d from d 10 through 110 of pregnancy or pseudopregnancy. At 110 d after onset of estrus, all gilts were slaughtered and numbers and(or) weights of fetuses, corpora lutea, placentae and the empty uterus were determined. Concentrations of estrogen sulfate and estrone, but not progesterone or prolactin, were associated with fetal number, total fetal weight, total placental weight or empty uterine weight. In contrast, only progesterone was highly correlated with number of corpora lutea. Results suggest that most conjugated estrogen, estrone and estradiol were of fetal-placental origin, whereas little, if any, placental production of progesterone or prolactin occurred. Increases in estrogen sulfate and estrone concentrations were observed at gestation d 30 and from d 70 to 100. The latter increase coincides with previously established increases in the rate of maternal mammary development and fetal growth.  相似文献   
992.
993.
994.
Evaluation of 845 cattle from Florida and Georgia for onchocerciasis indicated a significantly higher prevalence of infection with Onchocerca gutturosa and a significantly lower prevalence of infection with Onchocerca lienalis in the southern portion of Florida (subtropical region) than in the northern portion of Florida or in Georgia (temperature region). In all regions, prevalence of infection with O gutturosa was significantly higher than infection with O lienalis. In the temperate region, bulls were infected more often with O lienalis than were cows. Other sex-related differences in infection with either filariid was not found. Prevalence of infection with O lienalis was similar between age groups in all regions. Rates of infection with O gutturosa differed between age groups within and between subtropical and temperate regions. Examination of cervical and umbilical skin specimens for microfilariae detected an additional 6.6% of infected animals that had not been found by examination for adult worms. However, microfilariae were not found in 21.4% of animals that were positive for adult worms.  相似文献   
995.
A myopathy of horses at grass in east and south east Scotland was recognised in the autumn and winter of 1984 and the spring of 1985. The clinical signs resembled those of paralytic myoglobinuria. Grossly increased creatine kinase activities and the passage of dark brown urine were consistent features. However, the horses were not in training, most of them died and the muscles affected were those of posture and respiration rather than movement. The condition may be unrelated to nutritional myopathy because all the cases had adequate levels of alpha-tocopherol although their selenium status varied from normal to deficient. The clinical and pathological findings in 12 cases are presented and the differential diagnosis and possible aetiologies discussed.  相似文献   
996.
The purpose of this paper is to emphasize the importance of pulmonary auscultation for the clinician. It suggests a clarification and simplification of the terminology to be used which would be helpful to veterinary students and allow better communications between veterinarians. The interpretation of these sounds and the relationships to conditions and diseases of the lungs in cattle, horses, sheep and goats are discussed.  相似文献   
997.
998.
Clonidine (CL) is a alpha2-adrenergic agonist that produces analgesia in animals and humans by a non-opiate alpha2-adrenergic action in the spinal cord dorsal horn. The objective of this prospective randomized study was to investigate the clinical effects of CL/lidocaine (LD) combination administered by the subarachnoid route in sheep. Each sheep received each of three treatments, at no shorter than weekly intervals. Treatments consisted of 0.003 mg/kg CL, 1.2 mg/kg LD and a combination of CL (0.003 mg/kg) and LD (1.2 mg/kg) (CLLD). Subarachnoid injections were given in all animals between the last lumbar and first sacral vertebra. Heart rate (HR), arterial pressures, respiratory rate, rectal temperature, analgesia, sedation, and motor blockade were determined before drug administration (basal) and 5, 10, 15 and 30 min after drug administration, and at 30-min intervals until loss of analgesia occurred. The duration of analgesia after subarachnoid CLLD administration was 187 +/- 24 min (mean +/- SD), i.e. more than twice of that obtained with CL (99 +/- 19 min) or LD (55 +/- 4.4 min) alone. In all sheep, CL, administered either alone or with LD, induced moderate sedation. After subarachnoid administration of three treatments, all sheep had ataxia and subsequent sternal recumbency. The CL treatment causes decreases in blood pressure (diastolic arterial pressure and mean arterial pressure) and HR. Data suggest that the CLLD combination could be used subarachnoidally in sheep requiring prolonged surgery.  相似文献   
999.
A 6-year-old female Alaska Malamute dog was presented for evaluation of abdominal enlargement referred by a local veterinarian. On the history, the owner complained of chronic abdominal enlargement initiated more than 4 months ago, reduced appetite, occasional vomiting and general dullness. He also complained of greenish mucous intermittent vaginal discharge starting 10 days ago. The bitch was chronically treated with medroxiprogesterone acetate. A laparatomy was performed and fluid in the abdomen was found and aspirated during the surgery. Also a very fluid-filled distended uterus and a mass in the distal part of the left uterine horn were found. The mass was encapsulated by the omentum, but areas of necrosis and calcification were identified. Histopathological diagnosis was endometrial adenocarcinoma.  相似文献   
1000.
The predominant immunoglobulin isotype on most mucosal surfaces is secretory immunoglobulin A (SIgA), a polypeptide complex comprising two IgA monomers, the connecting J chain, and the secretory component. The molecular stability and strong anti-inflammatory properties make SIgA particularly well suited to provide protective immunity to the vulnerable mucosal surfaces by preventing invasion of inhaled and ingested pathogens. In contrast to SIgA, IgA in serum functions as an inflammatory antibody through interaction with FcalphaR on immune effector cells. Although IgA appears to share common features and protective functions in different species, significant variations exist within the IgA systems of different species. This review will give an overview of the basic concepts underlying mucosal IgA defence which will focus on the variations present among species in structure, antibody repertoire development, pIgR-mediated transport, colostral IgA content, hepatobiliary transport, and function with particular emphasis on the IgA system of the pig and dog. These interspecies variations emphasise the importance of elucidating and analysing the IgA system within the immune system of the species of interest rather than inferring roles from conclusions made in human and mouse studies.  相似文献   
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