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101.
Effects of exogenous insulin and body condition on metabolic hormones and gonadotropin-induced follicular development in prepuberal gilts 总被引:1,自引:0,他引:1
To determine influences of insulin and body condition on follicular growth, prepuberal gilts (n = 16) treated with pregnant mare's serum gonadotropin (PMSG) were used in a 2 X 2 factorial experiment with main effects of insulin (0 or .4 IU/kg every 12 h beginning at 1800 on the day before PMSG) and backfat depth (moderate, 25 +/- .8; high, 32 +/- .7 mm; P less than .0001). Body weights were similar. Blood sampling was at 6-h intervals for analyses of LH, FSH, growth hormone (GH), glucagon, cortisol, insulin, insulin-like growth factor-I (IGF-I), plasma urea nitrogen (PUN), nonesterified fatty acids (NEFA), testosterone, estradiol-17 beta, and progesterone. Ovaries were removed 75 h after PMSG treatment, and visible small (less than or equal to 3 mm), medium (4 to 6 mm), large (greater than or equal to 7 mm), and macroscopically atretic follicles were counted. Administration of insulin increased IGF-I in fluid of medium follicles (108.8 vs 60.7 ng/ml; SEM = 13.3; P less than .05). Neither insulin nor fatness affected hCG binding by granulosa cells (12.5 +/- 1.6 ng/10(6) cells) or numbers of large (16.7 +/- 2.6) and medium (10.4 +/- 2.3) follicles. However, insulin increased the number of small follicles (58.9 vs 29.9; SEM = 9.7; P less than .05) and reduced the number of atretic follicles (3.8 vs 11.3; SEM = 1.1; P less than .05). The predominant effect of insulin on reducing number of atretic follicles was in the small size class (.6 vs 6.9; SEM = .6, P less than .01). Follicular fluid estradiol and progesterone were not affected by treatments; however, testosterone concentrations in large follicles were lower in gilts with higher backfat (32.5 vs 59.9 ng/ml; SEM = 4.0; P less than .05). Systemic LH, FSH, glucagon, cortisol, PUN, NEFA, estradiol, and testosterone were not affected by insulin or level of feeding. However, GH was lower in gilts that had higher backfat (overall average of 3.2 vs 2.8 ng/ml; SEM = .1; P less than .05). Insulin reduced atresia and altered intrafollicular IGF-I independently of body condition and without sustained effects on other hormones. 相似文献
102.
Studies were conducted in an attempt to establish a relationship between fatty acid-binding protein (FABP) activity and marbling score in bovine longissimus muscle. Longissimus muscle was obtained from four 20-mo-old Charolais-Hereford crossbred heifers, three 16-mo-old Angus steers, and four 18-mo-old Angus steers. Immediately after slaughter, longissimus muscles were removed for the extraction of FABP. Supernatant (S104) fractions containing 41.3 to 144 mg of protein (depending on animal group) were eluted over Sephadex columns, and elution fractions were analyzed for the binding of radiolabeled palmitoyl-coenzyme A (CoA). Specific activities of FABP were 23, 32, and 101 nmol palmitoyl-CoA bound/mg protein for the Charolais-Hereford, 16-mo-old Angus, and 18-mo-old Angus cattle, respectively. These preliminary results suggested that longissimus muscle FABP activity was positively correlated with marbling score. To test specifically for this possibility, longissimus muscle was obtained at slaughter from each of four Wagyu steers, Angus heifers and Braford heifers. Marbling scores taken at the 12th-13th rib junction were Sm45, Sm43, and SI50 for the Wagyu, Angus, and Braford cattle, respectively. Interfascicular adipose tissue was exhaustively removed from sections of the 5th to 8th thoracic region of the longissimus muscle to eliminate any contribution of adipose tissue to FABP activity. For each animal, 300 mg of the S104 were eluted over Sephadex columns. Specific activities for the Wagyu, Angus, and Braford longissimus muscle FABP were 3.1, 3.8, and 3.9 pmol palmitoyl-CoA bound/mg protein, respectively, and were not different (P greater than .05) among the three animal groups.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
103.
Three duodenally cannulated, lactating Holstein cows were dosed with rare earth-labeled grain to evaluate effects of passage model, sampling site, and marker dosing time on digesta passage parameters. Cows were given ad libitum access to feed twice daily. Rare earth-labeled grain (applied by the 24-h immersion technique) was fed immediately before (Dy) or 2 h after (Yb) the morning feeding, and duodenal digesta and feces were sampled. Marker excretion curves were fit to a two-compartment, biexponential model, using curve peeling or to a series of two-compartment models, with one to six orders of gamma time-dependency in the fast compartment, using nonlinear regression. Passage estimates from the curve-peeled, biexponential model were similar to those from the best fit of the nonlinear models, which had three orders of gamma time-dependency. Ruminal passage rate of grain, averaged across models, sampling site, and dosing time, was .077/h. Estimates of time to first appearance of marker at the sampling site and mean retention times were longer (8 vs 1 h and 25 vs 17 h, respectively), but passage rates were similar, when determined from fecal compared with duodenal samples (P less than .05). Marker dosing time did not influence any of the parameters. It is concluded that both curve-peeling (linear regression) and nonlinear regression methods can be equally useful for evaluating passage kinetics of grain in dairy cows and that sampling site and time of marker dosing have little effect on passage parameter estimates. 相似文献
104.
Efficacy of mitoxantrone against various neoplasms in dogs 总被引:2,自引:0,他引:2
G K Ogilvie J E Obradovich R E Elmslie D M Vail A S Moore R C Straw K Dickinson M F Cooper S J Withrow 《Journal of the American Veterinary Medical Association》1991,198(9):1618-1621
One hundred twenty-six dogs with histologically confirmed, measurable malignant tumors were evaluated in a prospective study to determine the response to the antineoplastic drug mitoxantrone. Ninety-five dogs had been refractory to one or more treatment modalities (surgery, n = 57; chemotherapy other than mitoxantrone, n = 37; radiation, n = 4; whole body hyperthermia, n = 1). The extent of neoplastic disease was determined immediately before each dose of mitoxantrone was administered (1 to 10 doses, 2.5 to 5 mg/m2 of body surface area, IV) 21 days apart. Each dog was treated with mitoxantrone until the dog developed progressive disease or until the dog's quality of life diminished to an unacceptable level as determined by the owner or attending veterinarian. A partial or complete remission (greater than 50% volume reduction) was obtained in 23% (29/126) of all dogs treated. Tumors in which there was a partial or complete remission included lymphoma (11/32), squamous cell carcinoma (4/9), fibrosarcoma (2/9), thyroid carcinoma (1/10), transitional cell carcinoma (1/6), mammary adenocarcinoma (1/6), hepatocellular carcinoma (1/4), renal adenocarcinoma (1/1), rectal carcinoma (1/1), chondrosarcoma (1/2), oral malignant melanoma (1/12), cutaneous malignant melanoma (1/1), myxosarcoma (1/1), mesothelioma (1/1), and hemangiopericytoma (1/1). Our results indicated that mitoxantrone induces measurable regression in various malignant tumors in dogs. 相似文献
105.
Demographic data and treatment of small companion animals with lead poisoning: 347 cases (1977-1986)
R V Morgan L K Pearce F M Moore T Rossi 《Journal of the American Veterinary Medical Association》1991,199(1):98-102
Three hundred forty-seven cases of lead poisoning in small animals, diagnosed after 1976, were reviewed. The types of treatments used and their outcomes were analyzed. Changes in blood lead concentrations following various treatments, as well as the sources of lead exposure, were also reviewed. The geographic origins of the cases were traced, and demographic factors were studied to determine possible correlates that might explain the regional distribution of cases. 相似文献
106.
Comparison of culture, peroxidase-antiperoxidase reaction, and serum latex agglutination methods for diagnosis of chlamydiosis in pet birds 总被引:1,自引:0,他引:1
F M Moore M C McMillan M L Petrak 《Journal of the American Veterinary Medical Association》1991,199(1):71-73
Comparison was made among results of cloacal specimen culture, and cloacal swab specimen (cytologic) peroxidase-antiperoxidase (PAP), serum latex agglutination (LA), and tissue PAP assays for diagnosis of chlamydiosis in 144 birds. Swab specimen PAP findings correlated poorly with LA results and failed to predict the LA test result in any bird. Only 1 cloacal swab specimen was regarded as PAP-positive and was from the cloaca of a bird from which chlamydiae were isolated in culture. The sensitivity of swab specimen PAP, compared with culture results, was 33%, whereas specificity was 94%. In this study, swab specimen PAP was a less sensitive test, compared with culture, than was reported in a previous study. The sensitivity of LA in identifying birds that were cloacal culture-positive was poor; true-positive results were not detected, compared with culture results. The specificity of the LA method was 93%, compared with culture results. Results of the tissue PAP method correlated with culture results in the 3 birds for which both tests were performed. 相似文献
107.
108.
A. S. Moore § A. R. Imondi P. L. de Souza C. A. Wood † 《Veterinary and comparative oncology》2003,1(2):86-93
A colloidal dispersion formulation of 9‐aminocamptothecin (9‐AC) was administered intravenously to 10 dogs with previously untreated, spontaneously occurring, multicentric lymphoma. The dogs received a 72‐h infusion of 9‐AC at a rate of 46.5–51.25 µg m?2 h?1 (total dose range 3.35–3.69 mg m?2). This dose range was associated with myelosuppression, consisting principally of neutropenia with a nadir at 7 days following the start of infusion. Neutropenia and thrombocytopenia were the most common toxicoses and are most likely to be dose‐limiting toxicities; low‐grade gastrointestinal signs were rarely seen. Concentrations of 9‐AC lactone, as well as clinical toxicities, compare favourably with those found in humans. Tumour responses were seen in all treated dogs. Response to other chemotherapy, following cessation of 9‐AC treatment, was not obviously compromised even in dogs clinically resistant to 9‐AC. 9‐AC is a novel treatment drug for canine lymphoma, which appears to show great promise. 相似文献
109.
A wild-type isolate with similar morphological and phenotypic properties to Taylorella equigenitalis, the causative bacterial agent of contagious equine metritis (CEM), was referred for molecular identification by PCR amplification of the 16S rRNA gene. A species-specific PCR failed to yield a product compatible with that of T. equigenitalis. The direct sequencing of the universal 16S rRNA PCR amplicon suggested the presence of a Bacteroides sp., probably Bacteroides ureolyticus, with no consequent effects on the movement and transportation of the animal. Adoption of such a molecular means of identification through sequencing may aid in the identification of the atypical forms of Taylorella equigenitalis, as recently described, as well as differentiating this species from Taylorella asinigenitalis. 相似文献
110.
Melissa C. Paoloni DVM Dominique G. Penninck DVM DVSc Antony S. Moore BVSc MVSc 《Veterinary radiology & ultrasound》2002,43(6):562-567
In a retrospective study of 21 dogs with intestinal adenocarcinoma, the signalment, clinical presentation, laboratory findings, ultrasonographic features, treatment, and outcome were reviewed. Anorexia (n = 16), vomiting (n = 15), diarrhea (n = 10), and weight loss (n = 9) were the most common clinical signs reported. Ultrasonographic features that were evaluated included location, length, wall thickness, echogenicity, regional motility, layering, regional lymphadenopathy, and fluid accumulation proximal to the lesion site. All lesions were transmural and associated with complete loss of wall layering. Maximum wall thickening at the lesion site ranged from 7 to 17 mm (median 12 mm, mean 11.9 mm). Most of the dogs had a lesion measuring from 23 to 63 mm in length, (median 40 mm, mean 42 mm). Most intestinal lesions were poorly echogenic and had an irregular lumen. Fluid accumulation proximal to the lesion site was identified in 17 of 21 dogs, and in 13 of 17 dogs the fluid accumulation was considered moderate to severe. Regional lymphadenopathy and/or nodular mesentery/omentum were noted in 12 of 21 dogs. The tumor was located in small intestine for 15 dogs and in the colon for the remaining 6 dogs. Fifteen dogs were treated by surgical resection of the intestinal mass. Their median survival time was 233 days. Only gender appeared to influence survival. Female dogs lived a median of 28 days, whereas male dogs lived a median of 272 days. 相似文献