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191.
The toxic effects of an aqueous extract of Abrus precatorius were studied in 20 male white rats over a period of 18 days. The rats were divided into four groups of five rats per group. Those in Group A served as controls while the rats in Groups B, C and D were dosed per os with 400 mg/kg, 800 mg/kg and 1 600 mg/kg of the extract, respectively. Blood samples were collected for haematological and biochemical analysis and specimens of the liver, kidney and testes were taken for histopathological studies. The study showed that the extract of A. precatorius caused decreased levels of packed cell volume, haemoglobin concentration, red blood cell count, white blood cell count, mean corpuscular volume and mean corpuscular haemoglobin. The extract also resulted in increased levels of total serum protein, albumin, alanine amino transaminase, aspartate amino transferase, alkaline phosphatase and total bilirubin. Histologically, testicular degeneration characterized by decreased numbers of lining cells of the epithelium as well as reduction in sperm cells with presence of scattered Sertoli cells were noted. The study thus showed that aqueous extract of Abrus precatorius is toxic and caution should be exercised in its use for medicinal purpose.  相似文献   
192.
Free-ranging browsers such as the black rhinoceros (Diceros bicornis) consume a diet that contains tannins, whereas the diets offered to them in captivity consist mostly of items known to contain hardly any such secondary plant compounds. Tannins could have potentially beneficial effects, including the chelation of dietary iron (iron storage disease is a common problem in black rhinos). Here, we tested the acceptance, and the consequences on digestion variables, of a low-dose tannin supplementation in captive animals. Eight black rhinoceroses from three zoological institutions were used. Faecal output was quantified by total faecal collection. Diets fed were regular zoo diets supplemented with either tannic acid (T, hydrolysable tannin) or quebracho (Q, condensed tannins); overall tannin source intake increased at 5-15 g/kg dry matter (DM) in relation to regular zoo diets. Adaptation periods to the new diets were >2 months. Additional data were taken from one hitherto unpublished study. Data were compared to measurements in the same animals on their regular zoo diets. All animals accepted the new diets without hesitation. There was no influence of tannin supplementation on digestion coefficients of DM and its constituents, or faecal concentrations of short-chain fatty acids or lactate. Water intake did not increase during tannin supplementation. Should the inclusion of dietary tannin sources be an objective in the development of diets for captive rhinoceroses, moderate doses such as used in this study are unlikely to cause relevant depressions of digestive efficiency and will not interfere with bacterial fermentation in a relevant way.  相似文献   
193.
From September 1998 to September 1999, at drying off 397 cows on 73 Dutch farms were treated, with two antibiotic containing dry cow products (cloxacillin; penicillin-neomycin). Farms and cows were selected on an increased bulk milk somatic cell count (BMSCC) and individual cow somatic cell count. The objective of the trial was to compare the efficacy of both products under field conditions. Both products proved to be highly effective against streptococci and penicillin sensitive staphylococci. Because of the low incidence of infections caused by Escherichia coli and penicillin resistant staphylococci no conclusions could be drawn on differences in activity for these two pathogens. No significant differences were found between the two products in cure rate of existing infections at drying off, incidence of new infections during the dry period, incidence of clinical mastitis during the dry period and the course of the individual cow cell counts during the trial.  相似文献   
194.
The combined occurrence of ocular pigment deposition and glaucoma has been described in Cairn Terriers. Recently, this condition was also observed in two other breeds: the Boxer (two cases) and the Labrador Retriever (one case). Six dogs were referred to the Ophthalmology section of the Department of Clinical Sciences of Companion Animals and to a private referral clinic because of glaucoma or blindness in one or both eyes. In five cases ophthalmic examination showed pigment depositions in the sclera around the entire circumference of the perilimbal zone. Eight enucleated eyes (four eyes of two Cairn Terriers, three eyes of two Boxers and one eye of a Labrador Retriever) were examined microscopically. All eyes showed the same findings: an extensive infiltration of large melanin-containing cells with an eccentric nucleus, located in the iris, ciliary body, retina, choroids and sclera. Transmission electron microscopy of two of the examined eyes revealed that the morphology of most of these cells was consistent with melanophages. While reports in the veterinary literature concerning this condition are limited the cells concerned have been described to be melanocytes. Further research is needed to conclusively identify the cell type. As described in the present report, the histologic and transmission electron microscopic findings suggest a different etiology of the ocular pigment deposition and glaucoma compared with the pigment dispersal syndrome in humans.  相似文献   
195.
1. Although the poultry industry uses state-of-the-art equipment and up-to-date services, in Brazil it generally makes decisions involving all its production variables based on purely subjective criteria. This paper reports the use of artificial neural networks to estimate performance in production birds belonging to a South Brazilian poultry farm. 2. Recorded data from 22 broiler production breeder flocks were obtained, from April, 1998 to December, 1999, which corresponded to 689 data lines of weekly recordings. 3. These data were processed by artificial neural networks using the software NeuroShell 2 version 4.0 (Ward Systems Group). The artificial neural network models generated were compared and selected based on their largest determination coefficient (R2), lowest Mean Squared Error (MSE), as well as on a uniform scatter in the residual plots. The authors conclude that it is possible to explain the performance variables of production birds, with the use of artificial neural networks. 4. The method allows the decisions made by the technical staff to be based on objective, scientific criteria, allows simulations of the consequences related to these decisions, and reports the contribution of each variable to the variables under study.  相似文献   
196.
The objectives of this study were to compare glycerol and ethylene glycol at different concentrations as cryoprotectants and lycopene or cysteamine (with/without) as antioxidants in Tris extender for bull semen. Twenty‐four ejaculates were obtained from three bulls. Each ejaculate was split into four equal aliquots and diluted using both of the Tris extenders with glycerol (5% or 7%) or ethylene glycol (3% or 5%). After that, each extenders were split into three equal aliquots and added using both of the cysteamine 5 mm or lycopene 500 μg/ml, and control (without additives). The addition of 7% glycerol with cysteamine, 5% ethylene glycol with cysteamine and 3% ethylene glycol with cysteamine groups gave the lowest CASA motility than the other groups. However, 7% glycerol and 7% glycerol with lycopene resulted in a better rate of CASA progressive motility compared with that of other groups. Generally, all the lycopene groups signed better protective effects on acrosome and total morphology than the other groups. Glycerol 7% and 3% ethylene glycol with lycopene groups yielded to slight higher percentages of membrane integrity assessed by HOST than that of the other groups, but 7% glycerol with cysteamine and 3% ethylene glycol with cysteamine showed the worst percentages of membrane integrity. Glycerol 7% and 5% glycerol with lycopene gave rise to a higher value of VAP, VSL and VCL compared with that of the other groups. On the contrary, adding to 5% glycerol with cysteamine showed negative effect for VAP, VSL, VCL and ALH values. All cryoprotectant groups with lycopene decreased chromatin damage than the other groups. Ethylene glycol 3% led to lower non‐return rates of inseminated cows. However, this result was not considered to be statistically important.  相似文献   
197.

Background

Population characteristics and outcome of cats with arterial thromboembolism (ATE) managed in general practice (GP) have been poorly described.

Hypothesis

Cats with ATE presenting to GP are usually euthanized at presentation, but survival times >1 year are possible.

Animals

Cats with ATE managed by 3 GP clinics in the United Kingdom.

Methods

Records of cases presenting to GP over a 98‐month period (2004–2012) were reviewed. Cats with an antemortem diagnosis of limb ATE were included. Outcome information was obtained.

Results

Over 98 months, 250 cats were identified with ATE. Prevalence was approximately 0.3%. At presentation, 153 cats (61.2%) were euthanized, with 68/97 (70.1%) of the remaining cats (27.2% of the total population) surviving >24 hours after presentation. Of these, 30/68 (44.1%) survived for at least 7 days. Hypothermia (HR, 1.44; 95% CI, 1.002–2.07; P = .049) and management by Clinic 2 (HR, 5.53; 95% CI, 1.23–24.8; P = .026) were independent predictors of 24‐hour euthanasia or death. For cats surviving >24 hours, hypothermia (HR, 2.25; 95% CI, 1.12–4.48; P = .021) and failure to receive aspirin, clopidogrel, or both (HR, 8.26; 95% CI, 1.39–50; P = .001) were independent predictors of euthanasia or death within 7 days. For cats that survived ≥7 days, median survival time was 94 (95% CI, 42–164) days, with 6 cats alive 1 year after presentation.

Conclusions

Although 153/250 cats were euthanized at presentation, 6 cats survived >12 months. No factors were identified that predicted euthanasia on presentation.  相似文献   
198.
Slaughterhouse sampling and examination of urogenital tracts of 499 sows and gilts culled for reproductive reasons from 21 Hungarian herds were performed over a 6-year period. The aim was to estimate the prevalence of different urogenital tract lesions, and to provide sensitivity and specificity estimates for macroscopic and bacteriological examinations in the diagnosis of urocystitis and endometritis. Furthermore, the association between endometritis and urocystitis was assessed. The prevalence of main lesions of the urogenital tract was similar to that reported in other studies. The 'sensitivity' of macroscopic and bacteriological methods was determined statistically by taking histopathology as the 'Gold Standard'. As a result, the 'sensitivity' of macroscopic methods for the diagnosis of endometritis and urocystitis was < or = 18.1% and 47.9%, respectively, while the 'sensitivity' of bacteriology for the diagnosis of the same conditions was < or = 31.8% and 63.0%, respectively. The presumed positive association between urocystitis and endometritis was confirmed; it was not confounded by parity. Animals affected by urocystitis had a 3.5 times higher odds to simultaneously have endometritis than animals without urocystitis.  相似文献   
199.
A feeding trial was carried out with turkey poults, which were fed a diet containing 10(10) viable probiotic E. faecium NCIB 10415 cells/kg feed. Samples of the intestinal tract were analyzed for lactate, colony forming units of total anaerobic bacteria, lactic acid bacteria, enterobacteria and enterococci. Furthermore, metabolic activity of total eubacterial, lactobacilli and enterococci was recorded in selected RNA-extracts with specific ribosomal RNA oligonucleotide probes. Animals fed the probiotic diet showed continously increasing lactate concentrations throughout the sampling period up to day 42 of life. No correlation was found for colony forming units (cfu) of lactic acid bacteria, but metabolic activity of lactobacilli showed very close relation to continously increasing lactate concentrations. Throughout the feeding trial, enterococci in the control group continously increased to a maximum of 10(4) cfu/g wet weight, but 10-fold higher enterococci cfu were generally found in the treated group. However, rRNA content as measure for metabolic activity showed a drastic decline in both groups after high metabolic activities on day 7. This study shows that E. faecium NCIB 10415 (E. faecium SF68) stimulates other lactic acid bacteria in the small intestine, especially lactobacilli.  相似文献   
200.
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