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601.
The possible effect of fenchlorphos, 0-0-dimethy1-0-(2.4.5-trichlorophenyl) phosphorothioate, upon the reproductive endocrinology in blue foxes (Alopex lagopus) was investigated. Five females were administered fenchlorphos orally at a dose of 100 mg/kg daily from 10 days before oestrus and up to the 21st day of gestation. This dose represents the therapeutic dose for the treatment of sarcoptic mange. Blood samples were collected for the analyses of progesterone, oestradiol-17β and luteinizing hormone (LH) in plasma. The vixens were ovario-hysterectomized on day 23, except 1 animal in the control group which was operated on day 17. Additionally, sperm quality and mating performance in 3 male blue foxes, which were administered 100 mg/kg fenchlorphos daily during the first 3 weeks of the mating season, were examined.Pregnancy was recorded in 2 medicated and 4 control animals. No pathological changes were observed in the uterus and the ovaries. The plasma concentrations of the hormones were similar to those obtained from the control group. No evidence of any disturbances concerning spermatogenesis in the males was observed. However, their libido appeared to be reduced. None of the males achieved a mating during and after the period of medication.  相似文献   
602.
The glaucomas are vision-threatening diseases that commonly result in blindness. In addition to knowledge of the at-risk breeds and predisposing factors for glaucoma as well as the clinical signs of the disease, regular IOP screening with tonometry is required to confirm glaucoma and to monitor the status of the eye. Early intervention with a combination of medications that are capable, in a given species, of reducing aqueous production and increasing aqueous outflow as well as potentially reducing progressive neurosensory degeneration is key to the medical management of this disease.  相似文献   
603.
Chelonians (turtles, tortoises, and terrapins) are not as well represented in private reptile collections as are snakes and lizards. Thismay be due in part to the fact that they often require more space and time for proper care. Nonetheless, they are still popular pets.Unfortunately, many people are not aware of what constitutes proper care for these animals. This article will discuss basic captive husbandry and nutrition issues of common chelonians, as well as recognizing illness, capture and restraint, sample collection, medication administration, and preventive care.  相似文献   
604.
Three outbreaks of late-gestation abortions in does and ulcerative posthitis in bucks, associated with caprine herpes virus-1 (CHV-1), in California are described. In herd A, 10 of 17 does aborted in a 7-day period, whereas in herd B, 4 of 130 does aborted in a 45-day period and in herd C, 100 of 300 does aborted in a 3-week period. Most fetuses had multifocal pinpoint depressed foci with a zone of hyperemia on external and cut surfaces of the kidneys, liver, lungs, and adrenal glands. Histologically, scattered multifocal areas of necrosis with mild neutrophilic infiltrate were observed in kidneys, brain, liver, adrenal glands, and lungs of most fetuses of the 3 herds. Large amphophilic intranuclear inclusion bodies, which displaced the chromatin, were observed in cells within and around the necrotic foci in kidneys and adrenal glands. Particles 85-113 nm in size with morphology compatible with herpes virus were observed in the nuclei of these cells when examined by electron microscopy. Irregular, shallow, red ulcers were observed in the prepuce of 1 buck from herd C. Prepuce biopsies from this animal had necrosis of the superficial mucosal epithelium and severe submucosal lymphoplasmocytic infiltrates. Large intranuclear amphophilic inclusion bodies were observed in most cells of the stratum spinosum of the preputial epithelium, but no viral particles were observed in these cells. Caprine herpes virus-1 was isolated from tissue pools of fetuses from the 3 herds but not from prepuce biopsies. Positive results were obtained when tissues of a fetus from herd C were processed by a polymerase chain reaction technique to amplify the amino terminus of the glycoprotein C gene of CHV-1. Sera from aborted does from herds B and C and from the 3 bucks from herd C had high antibody titers to CHV-1. The results presented here support the hypothesis that the male goat is involved in the transmission of CHV-1. However, other forms of transmission cannot be ruled out.  相似文献   
605.
Novel 5-amino-1-phenylpyrazol-4-yl alkyl ketones were synthesised and their herbicidal properties evaluated. Active compounds in the series induced accumulation of protoporphyrin IX in etiolated cucumber cotyledons and caused light-dependent herbicidal effects in 21-day-old cucumber plants. Structural features of the pyrazoles that contributed to herbicidal potency were found to be a high degree of halogen substitution in the 1-phenyl ring, no substitution in the pyrazole 3-position, and an ethyl group as the alkyl component of the ketone. The structure of 1-[5-amino-1-(2,4,6-trichlorophenyl)pyrazol-4-yl]-2-methylpropan-1-one was determined by X-ray crystallography.  相似文献   
606.
The hydrolysis kinetics of the dicarboximide fungicides procymidone, vinclozolin and chlozolinate in neutral and alkaline solutions of pH 60 to 13·7 at 25°C have been determined conjointly by ultraviolet spectrophotometry and by high performance liquid chromatography. Under alkaline conditions, the fungicides undergo attack by the hydroxide ion on a specific carbonyl group and the rate of hydrolysis increases proportionally to the hydroxide ion concentration. Procymidone gives quantitatively and irreversibly 2-(3,5-dichlorophenylcarba-moyl)-l,2-dimethylcyclopropanecarboxylate. The reaction is not subject to general base catalysis and experimental data are in agreement with a rate-determining attack by the hydroxide ion. After a rapid hydrolytic loss of the ethoxycarbonyl substituent from chlozolinate, the dicarboximide ring cleavage of the two other fungicides leads, by mechanisms which differ with respect to the type of base catalysis and the rate-determining step, to the corresponding anilides, producing as intermediates the carbamic acids, which undergo loss of carbon dioxide. The hydrolysis of vinclozolin and chlozolinate yields, respectively, N-(3,5-dichloro-phenyt)-2-hydroxy-2-methylbut-3-enanilide and N-(3,5-dichlorophenyl)-2-hydroxy-propanilide.  相似文献   
607.
608.
The objective of this study was to evaluate the effect of replacing Tifton 85 hay (0, 33, 66, or 100 %) with by castor bean hulls on the intake and nutrient digestibility and performance of 28 noncastrated lambs, averaging 7 months in age, 19.5?±?2.0 kg average live weight, fed on diets based on forage cactus. The animals were housed in individual pens for 100 days. The digestibility trial occurred 40 days after the start of the performance using LIPE® as an external indicator for estimating fecal dry matter production. The replacement of hay with Castor beans hulls linearly decreased the intakes of dry matter, neutral detergent fiber, organic matter, and crude protein and reduced the digestibility coefficients of the dry matter, neutral detergent fiber, organic matter content, crude protein, and total digestible nutrient content. The hot carcass and true carcass yields were not influenced by the treatments and the feed conversion increased linearly. The empty body weight, live weight at slaughter, hot and cold carcass weights, total gain, and average daily gain decreased linearly with the replacement. The replacement of Tifton 85 hay with castor bean hulls reduced the intake of dry matter, crude protein and energy, consequently reducing the performance of the animals. However, as the regression coefficients were of low magnitude, data were subjected to analysis of variance and means were compared using the Dunnett test with diet without castor bean hulls set as the control treatment. The Tifton 85 hay can be replaced up to 66 % by castor bean hulls in finishing diets for lambs.  相似文献   
609.
OBJECTIVE: To evaluate the effects of diet restriction on development of radiographic evidence of hip joint osteoarthritis in dogs. DESIGN: Longitudinal cohort study. ANIMALS: 48 Labrador Retrievers from 7 litters. PROCEDURES: Forty-eight 6-week-old puppies from 7 litters were paired with littermates by sex and weight, and each pairmate was randomly assigned to 1 of 2 groups of 24 dogs each. Starting at 8 weeks of age, 1 group was fed ad libitum (control fed) and the other was fed 25% less (restricted fed) of the same diet for life on a pairwise basis. The dogs' hip joints were radiographed in the standard ventrodorsal hip-extended view at multiple intervals prior to 1 year of age and at annual intervals thereafter on the basis of birth anniversary. A board-certified radiologist unaware of group assignment scored the radiographs for evidence of osteoarthritis. RESULTS: Prevalence of radiographic evidence of hip joint osteoarthritis in all dogs increased linearly throughout the study, from an overall prevalence of 15% at 2 years to 67% by 14 years. Restricted-fed dogs had lower prevalence and later onset of hip joint osteoarthritis. Median age at first identification of radiographic evidence of hip joint osteoarthritis was significantly lower in the control-fed group (6 years), compared with the restricted-fed group (12 years). CONCLUSIONS AND CLINICAL RELEVANCE: Restricted feeding delayed or prevented development of radiographic signs of hip joint osteoarthritis in this cohort of Labrador Retrievers. Lifetime maintenance of 25% diet restriction delayed onset and reduced severity of hip joint osteoarthritis, thus favorably affecting both duration and quality of life. In addition, the data indicated that development of hip joint osteoarthritis was not bimodal in these dogs but occurred as a continuum throughout life.  相似文献   
610.
The objective of this study was to determine common tumor types that occur on the canine scrotum in relation to other cutaneous locations and to identify potential risk factors for specific scrotal tumor development. A retrospective study was conducted and the database of pathology reports from the Surgical Pathology Service of the Department of Pathology and Toxicology, School of Veterinary Medicine, University of Pennsylvania from 1986 to 2010 was searched for canine neoplastic scrotal and non-scrotal cutaneous lesions. Neoplastic lesions were evaluated based on diagnosis, breed, age, and number and location of tumors (scrotal versus non-scrotal cutaneous). Mast cell tumor, melanocytoma, malignant melanoma, vascular hamartoma, hemangiosarcoma, hemangioma, and cutaneous histiocytoma were the most common tumor types identified on the canine scrotum. Breed predispositions and mean age at diagnosis were identified for each tumor type and should be considered when planning surgical excision of a canine scrotal tumor.  相似文献   
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