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11.
Four mature pony geldings weighing an average of 134 kg and fitted with ileal cannulas were used in a 4×4 Latin square experiment to determine the digestibility of soybean meal (SBM) protein in different segments of the equine digestive tract at various levels of protein intake. A complete basal corn-based diet was supplemented with SBM to formulate four diets with increasing crude protein. The diets, labeled A (basal), B, C and D, contained 4.9%, 9.5%, 14% and 16.5% crude protein (as fed), and provided nitrogen, per feeding, at approximately 44.8, 84.3, 123.9 and 146.3 mg/kg of body weight, respectively. Chromic oxide was fed to measure ileal flow and fecal excretion. Digestion and absorption of nitrogen was determined from changes in nitrogen: chromium ratios, and true digestion of nitrogen was computed by regression analysis. True total tract digestion of nitrogen was 95.7%. True digestibility of nitrogen in the small intestine over the range of linearity was 72.2%, while true digestibility of nitrogen reaching the large intestine was 89.8%. These data indicate that the protein in SBM was almost completely digested in the equine digestive tract. Furthermore, approximately 75% of the digestible protein was digested prececally when nitrogen intake was less than approximately 125 mg/kg of body weight per feeding.  相似文献   
12.
Mature ponies fitted with permanent ileal cannulas were used in two 3×3 Latin square experiments to quantify prececal, postileal and total tract digestion of N. In trial 1, corn, oats and sorghum were each fed with coastal Bermuda grass hay in 75:25 ratios. Apparent prececal digestibilities were similar (P>.05) and averaged 46.6%. By-difference procedures were employed to calculate digestibility of the cereal grain N only and apparent prececal N digestibility averaged 57.1%. In trial 2, a basal corn and hay diet was supplemented with cottonseed meal and soybean meal. Apparent total tract N digestibilities were similar (P>.05) across treatments, and prececal digestibility averaged 45.6%. By-difference calculations were used to determine digestibility of SBM and CSM N alone. Apparent prececal digestibility of SBM was 52.5% and was lower (P<.05) than 81.2% for CSM. It is possible that inadequate or excessive heat treatment of SBM affected enzymatic digestion. True digestibility of total rations fed in trial 2 was estimated by linear regression of nitrogen digested on nitrogen intake or N presented to the large intestine. True N digestibility of diets containing SBM and CSM was 54.7% and 69.4%, respectively.  相似文献   
13.
An avirulent, wild-type avian Escherichia coli (E. coli Av) was electrotransformed with a plasmid coding for the production of microcin 24 (pGOB18) and was designated E. coli AvGOB18. The transformant inhibited the growth of seven serotypes of Salmonella commonly associated with colonization and contamination of poultry products and seven strains of E. coli O157:H7 in the in vitro colicin/microcin assay. The transformant did not inhibit the replication of multiple isolates of Listeria monocytogenes or Campylobacter jejuni in similar assays. The transformant is nonconjugative, indicating that the plasmid would not be transmitted to other intestinal microflora in the environment. The transformant also survived in sterile tap and deionized water incubated at 25 C and 37 C in the laboratory for 30 days and was recovered from drinkers and birds in in vivo floor pen studies. In in vivo studies, E. coli AvGOB18 did not colonize the intestinal tract of broiler chicks when given as a single or multiple dose and did not reduce the Salmonella load in the broilers. But Salmonella typhimurium was reduced significantly in the intestinal tracts of broiler chickens when E. coli AvGOB18 was administered continually in the water supply.  相似文献   
14.

Objective

To determine the effect of fentanyl on the induction dose of propofol and minimum infusion rate required to prevent movement in response to noxious stimulation (MIRNM) in dogs.

Study design

Crossover experimental design.

Animals

Six healthy, adult intact male Beagle dogs, mean ± standard deviation 12.6 ± 0.4 kg.

Methods

Dogs were administered 0.9% saline (treatment P), fentanyl (5 μg kg?1) (treatment PLDF) or fentanyl (10 μg kg?1) (treatment PHDF) intravenously over 5 minutes. Five minutes later, anesthesia was induced with propofol (2 mg kg?1, followed by 1 mg kg?1 every 15 seconds to achieve intubation) and maintained for 90 minutes by constant rate infusions (CRIs) of propofol alone or with fentanyl: P, propofol (0.5 mg kg?1 minute?1); PLDF, propofol (0.35 mg kg?1 minute?1) and fentanyl (0.1 μg kg?1 minute?1); PHDF, propofol (0.3 mg kg?1 minute?1) and fentanyl (0.2 μg kg?1 minute?1). Propofol CRI was increased or decreased based on the response to stimulation (50 V, 50 Hz, 10 mA), with 20 minutes between adjustments. Data were analyzed using a mixed-model anova and presented as mean ± standard error.

Results

ropofol induction doses were 6.16 ± 0.31, 3.67 ± 0.21 and 3.33 ± 0.42 mg kg?1 for P, PLDF and PHDF, respectively. Doses for PLDF and PHDF were significantly decreased from P (p < 0.05) but not different between treatments. Propofol MIRNM was 0.60 ± 0.04, 0.29 ± 0.02 and 0.22 ± 0.02 mg kg?1 minute?1 for P, PLDF and PHDF, respectively. MIRNM in PLDF and PHDF was significantly decreased from P. MIRNM in PLDF and PHDF were not different, but their respective percent decreases of 51 ± 3 and 63 ± 2% differed (p = 0.035).

Conclusions and clinical relevance

Fentanyl, at the doses studied, caused statistically significant and clinically important decreases in the propofol induction dose and MIRNM.  相似文献   
15.
16.
In this study the quality of digital and analog radiography in dogs was compared. For this purpose, three conventional radiographs (varying in exposure) and three digital radiographs (varying in MUSI-contrast [MUSI = MUlti Scale Image Contrast], the main post-processing parameter) of six different body regions of the dog were evaluated (thorax, abdomen, skull, femur, hip joints, elbow). The quality of the radiographs was evaluated by eight veterinary specialists familiar with radiographic images using a questionnaire based on details of each body region significant in obtaining a radiographic diagnosis. In the first part of the study the overall quality of the radiographs was evaluated. Within one region, 89.5% (43/48) chose a digital radiograph as the best image. Divided into analog and digital groups, the digital image with the highest MUSI-contrast was most often considered the best, while the analog image considered the best varied between the one with the medium and the one with the longest exposure time. In the second part of the study, each image was rated for the visibility of specific, diagnostically important details. After summarisation of the scores for each criterion, divided into analog and digital imaging, the digital images were rated considerably superior to conventional images. The results of image comparison revealed that digital radiographs showed better image detail than radiographs taken with the analog technique in all six areas of the body.  相似文献   
17.
Convivial and playful, the ferret has cohabited with humans for hundreds of years. Maintenance of this mustelid's health and quality of life is paramount for the endurance of the human-animal bond. This review article for veterinary care givers, veterinarians, and staff, encompasses discussions on: husbandry, clinical techniques, prevalent diseases, history taking, physical examination, vaccination, and pain recognition. This article also enables the veterinary community to contribute to the care and welfare of ferret patients by offering facts to distinguish these animals from dogs and cats.  相似文献   
18.
BACKGROUND: The potential of systemic neonicotinoid insecticides to control potato leafhopper, Empoasca fabae (Harris), a damaging pest of wine grapes in the eastern United States, was investigated. Soil or foliar applications were made to potted or field‐grown vines, and the response of leafhoppers was determined in clip cages over the following month on young or mature leaves. RESULTS: Foliar application of imidacloprid caused immediate and long‐lasting reductions in E. fabae survival on both leaf ages, whereas the activity of soil‐applied imidacloprid was delayed. Clothianidin, imidacloprid and thiamethoxam all provided long‐lasting reduction in leafhopper survival on young and mature foliage when applied through either delivery route. However, the percentage of moribund nymphs was significantly greater on foliar‐treated vines and increased over time in mature and immature leaves compared with soil‐treated vines. Residue analysis of foliar‐applied imidacloprid showed an 89% decline in mature leaves from day 1 to day 27, and a 98% decline in immature leaves over the same time period. Comparison of soil‐applied clothianidin, imidacloprid and thiamethoxam in field‐grown vines showed significant reduction in E. fabae only on mature leaves of vines treated with thiamethoxam. CONCLUSIONS: Neonicotinoids can control E. fabae in small vines, even in rapidly expanding foliage where this pest causes greatest injury. Soil application provides superior long‐term vine protection because declining residues on foliar‐treated vines lead to suboptimal activity within 2–3 weeks. Vineyard managers of susceptible cultivars may take advantage of this approach to E. fabae management by using foliar applications of the three neonicotinoids tested here, or by using soil‐applied thiamethoxam. Copyright © 2011 Society of Chemical Industry  相似文献   
19.
OBJECTIVE: To describe cardiac lesions and identify risk factors associated with myocarditis and dilated cardiomyopathy (DCM) in beach-cast southern sea otters. ANIMALS: Free-ranging southern sea otters. PROCEDURE: Sea otters were necropsied at the Marine Wildlife Veterinary Care and Research Center from 1998 through 2001. Microscopic and gross necropsy findings were used to classify sea otters as myocarditis or DCM case otters or control otters. Univariate, multivariate, and spatial analytical techniques were used to evaluate associations among myocarditis; DCM; common sea otter pathogens; and potential infectious, toxic, and nutritional causes. RESULTS: Clusters of sea otters with myocarditis and DCM were identified in the southern aspect of the sea otter range from May to November 2000. Risk factors for myocarditis included age, good body condition, and exposure to domoic acid and Sarcocystis neurona. Myocarditis associated with domoic acid occurred predominantly in the southern part of the range, whereas myocarditis associated with S. neurona occurred in the northern part of the range. Age and suspected previous exposure to domoic acid were identified as major risk factors for DCM. A sample of otters with DCM had significantly lower concentrations of myocardial L-carnitine than control and myocarditis case otters. CONCLUSIONS AND CLINICAL RELEVANCE: Cardiac disease is an important cause of death in southern sea otters. Domoic acid toxicosis and infection with S. neurona are likely to be 2 important causes of myocarditis in sea otters. Domoic acid-induced myocarditis appears to progress to DCM, and depletion of myocardial L-carnitine may play a key role in this pathogenesis.  相似文献   
20.
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