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71.
The objective of this study was to establish a reference base for respiratory variables (respiratory rate [R(R)], inspiratory and expiratory time [T(i) and T(e)], peak inspiratory and expiratory pseudoflow [PIF and PEF], tidal volume [V(T)], minute ventilation [V(E)] and enhanced pause [Penh]) of healthy cats by use of barometric whole body plethysmography (BWBP). Eighteen healthy European cats (10 male, 8 female) were studied from the age of 3 to 13 months in order to assess growth- and gender-related changes of BWBP variables. Chest radiographs and bronchoalveolar lavage cytology were performed to confirm pulmonary health status. Diurnal changes were investigated every 2 h over a period of 24 h when the cats were adult. V(T), V(E), PIF and PEF significantly increased during somatic growth and were higher in males than in females, whereas R(R), T(i), T(e), T(e)/T(i) ratio, PEF/PIF ratio and Penh remained unchanged and were not affected by gender. When measured over 24 h, Penh, T(e) and T(i) were significantly increased in the early morning hours (04:00 h), whereas R(R), PIF and PEF were decreased at that time. This study provides reference values of BWBP variables for healthy male and female cats and indicates when circadian changes might be observed.  相似文献   
72.
73.
Western blot analysis showed that sweat gland cells from freely sweating horses expressed the water channel aquaporin-5 (AQP-5). Immunohistochemistry revealed a strong AQP-5-like activity reaction at the apical membrane of the glandular secretory cells, which was absent from the surrounding myoepithelium and all other skin structures. In anhidrotic horses, AQP-5 was also found at the apical membrane of the luminal sweat gland cells, but the level of expression reduced with the length of time that the animal had displayed anhidrosis. The level of AQP-5 expression was substantially reduced in animals with long-term anhidrosis, hence implicating water channel impairment as a possible factor in the development of this disorder.  相似文献   
74.
Nitric oxide (NO), prostaglandin E2 (PGE2), and the activity of neutral metalloproteinases (NMPs) were measured in conditioned media of equine synovial membrane and articular cartilage explant cultures from horses with normal joints (n = 7) and from horses affected with moderate (n = 7) or severe osteoarthritis (n = 14) as judged by macroscopic appearance. Normal articular cartilage appeared glossy and bluish-white, was of normal thickness and showed no evidence of discolouration, fibrillation or other cartilage discontinuity. Slight discolouration and fibrillation or minor clefts of the cartilage were considered as moderate OA, whereas erosions of articular cartilage down to the subchondral bone were considered as cases of severe OA. Explant cultures of equine synovial membrane and articular cartilage released the local mediators, NO and PGE2, as well as detectable levels of NMP activity into culture media. Concentrations of NO were higher in articular cartilage explants compared to synovial membrane explants, whereas concentrations of PGE2 were higher in synovial membrane explants. The NMPs with collagenolytic activities were similar in both explant cultures, whereas gelatinolytic activities were higher in synovial membrane explant cultures and caseinolytic activities were generally higher in articular cartilage explant cultures. Furthermore it was shown that concentrations or enzyme activities increased according to the severity of disease of the joints. Concentrations for NO, collagenolytic and gelatinolytic NMPs were relatively stable, whereas PGE2 and caseinolytic NMP concentrations increased over time in culture.  相似文献   
75.
Under field conditions, the diagnosis of foal's diseases relies almost exclusively on the physical examination. As the signs of illness in the equine neonate are frequently vage and non-localizing, the diagnosis of diseases may be problematic. This often causes misinterpretations and leads to ineffective prophylaxis and treatment. The purpose of this study was to evaluate the usefulness of diagnostic ultrasonography of the foal's abdomen under field conditions to provide an optimized technique and to describe the normal findings. Diagnostic ultrasonography of the abdomen was performed after obtaining clinical history and passing the physical examination of 25 foals without signs of abdominal problems. The foals were scanned in a stable box, being restrained by three persons in semi-lateral recumbency. Usually, sedation was not necessary. The ventral abdominal wall was clipped, a generous amount of ultrasound coupling gel was applied and massaged on the skin surface. The ultrasonographic examination was carried out using a portable sector scanner ("Microimager 2000", Ausonics) with 5.0 and 7.5-MHz transducers or a combined 5.0 and 7.5-MHz transrectal linear-array scanner ("450 Enhanced", Pie Medical). Employing the 5.0-MHz sector scanner first, the abdomen was explored from caudal to cranial in left and right semi-lateral recumbency. The 7.5-MHz scanner was used to attain higher resolution of certain structures. The sector scanner turned out to be suitable under field conditions and adequate to examine the abdominal organs. The transrectal linear-array scanner also provided the most important informations, although it was difficult to maintain a good contact area of the scan head. By ultrasonography it was possible to identify the urinary bladder, kidneys, spleen, liver and part of the gastrointestinal tract. Thus, application of ultrasound could successfully be performed on newborn foals under field conditions.  相似文献   
76.
Benzimidazole anthelmintic drugs are widely used in veterinary practice. Albendazole sulphoxide (ABZSO) is a benzimidazole drug with two enantiomers, as a consequence of a chiral centre in the sulphoxide group. The kinetics of these enantiomers were studied in male and female sheep. Plasma samples were obtained from the animals between 0.5 and 72 h after oral administration of 7.5 mg/kg of a racemic formulation of ABZSO (total-ABZSO). After a liquid–liquid extraction, the samples were analysed by HPLC to determine the concentrations of total-ABZSO and of the sulphone metabolite (ABZSO2). During the chromatographic analysis, the ABZSO peak was collected and reanalysed by an HPLC technique using a Chiral AGP column to quantify the enantiomeric proportion therein. After kinetic analysis, the AUCs obtained for the (+)-ABZSO were 5.8 and 4.0 times higher than those for the (–)-ABZSO in male and female animals, respectively. The mean residence times were 23.4 and 16.1 h for (+)-ABZSO and 22.2 and 17.4 h for (–)-ABZSO for male and female animals, respectively. The only significant difference between the sexes (p<0.05) was in the T max of the (–)-ABZSO. Comparing both enantiomers within each sex, significant differences were found in all the kinetic parameters. Finally, no kinetic differences were found between sex for total-ABZSO or ABZSO2.  相似文献   
77.
1991,1992和1993年每年的9月7日~11月7日分别选用80头2岁春季初产母牛进行断奶和放牧试验。试验设计包括2个断奶处理和2个散牧处理(每个处理20头母牛),放牧处理分为天然沙岗草地和地下灌溉再生人工草地2个处理,断奶处理分为9月7日断奶和11月7日断奶2个处理。9月7日断奶后犊牛在人工草地放牧。食道瘘管牛从天然草地和人工草地上采食的日粮粗蛋白含量以有机质(OM)为基础分别为7.6%和12.3%,天然草地和人工草地牧草体外有机质消化率分别为55.1%和61.1%。年度×放牧处理或断奶×放牧处理间的互作效应不显著(P<0.01)。不同年度间试验牛有机质采食量差异较大,1991年为7.7kg/d,1992年为10.5kg/d,放牧和断奶处理间有机质采食量差异不显著(P>0.10)。人工草地上放牧母牛的增重和体况均比天然草地放牧母牛的好。于奶牛的增重和体况明显优于泌乳牛(P<0.01)。人工草地上放牧的泌乳牛可维持体重和体况,而天然草地上放牧的泌乳牛体重下降且体况变差。人工草地上放牧的未断奶犊牛比天然草地上放牧的多增重28.8 kg(P<0.01),比人工草地上放牧的断奶犊牛多增重34.4kg。人工草地上放牧的断奶犊牛的增重和天然草地上放牧的未断奶犊牛的增重差异不显著(P>0.10)。研究结果表明:9~10月份干奶牛和再生人工草地上放牧的母牛增  相似文献   
78.
OBJECTIVE: To evaluate the reliability of taurine concentrations measured in a single urine sample obtained from dogs 8 hours after eating, compared with taurine concentrations measured in 24-hour urine samples. ANIMALS: 18 healthy Beagles. PROCEDURE: After emptying the urinary bladder by transurethral catheterization, dogs were fed a canned maintenance diet. Approximately 8 hours later, urine, plasma, and serum samples were obtained for determination of fractional urinary excretion of taurine and urine taurine-to-creatinine concentration ratios (Utaur:Ucr). Results were compared with 24-hour urinary taurine excretion rate. RESULTS: Unbound and total fractional urinary taurine excretion correlated well with unbound and total 24-hour urinary taurine excretion. However, bound fractional urinary taurine excretion correlated poorly with bound 24-hour urinary taurine excretion. Unbound and total Utaur:Ucr correlated well with unbound and total 24-hour urinary taurine excretion. However, bound Utaur:Ucr correlated poorly with bound 24-hour urinary taurine excretion. CONCLUSION AND CLINICAL RELEVANCE: Fractional urinary excretion of unbound and total taurine, and unbound and total Utaur:Ucr are reliable indicators of 24-hour urinary unbound and total taurine excretion in healthy dogs. However, determination of 24-hour urinary taurine excretion is recommended for evaluating urinary bound taurine concentrations of dogs.  相似文献   
79.
Effects of the halothane genotype and slaughter weight on texture of pork   总被引:4,自引:0,他引:4  
The objective of this study was to investigate the effects of the halothane (HAL) genotype, slaughter weight (SW), and the HAL x SW interaction on compositional and textural traits of raw and cooked pork. Pigs were bred to exhibit one of the three HAL genotypes (NN, Nn, and nn) with otherwise equivalent genomes. The nn halothane reactors are known to typically produce PSE pork, whereas NN pigs do not typically produce PSE pork. Pietrain x Large White gilts and boars, all with verified Nn genotype (by DNA test), were mated to obtain F2 littermates of the three HAL genotypes. These pigs were slaughtered at either 101 +/- 3 ("light") or 127 +/- 3 ("heavy") kg BW and were evaluated for longissimus muscle traits. The pH at .5 h after death (pH1) was 6.35, 6.13, and 5.68 in NN, Nn, and nn pigs, respectively. Sarcomere length was greater in nn than in NN and Nn pigs (1.94 vs 1.83 and 1.85 microm, respectively). Mechanical resistance was higher in nn than in NN pigs for both raw and cooked meat. Meat from nn pigs was judged by a trained panel to be less rough, more cohesive, harder, more fibrous, less granular, more elastic, and less easy to swallow than meat from NN pigs. For most traits under study, the heterozygotes were intermediate between the homozygotes but closer to NN than to nn pigs. Muscle from heavy pigs had longer sarcomeres and less moisture than muscle from light pigs. The n allele of the HAL gene unfavorably affects pork texture, and this effect is maintained throughout the range of 101 to 127 kg BW.  相似文献   
80.
正4知识缺口和未来研究需求4.1反刍动物目前,人们对反刍动物放牧时的行为需求知之甚少。因此,在不考虑营养方面的条件时,反刍动物不进行放牧,而在室内向其提供全价混合日粮(Total Mixed Ration,TMR)日粮,这种方式是否对动物福利来说会更好,还需要进一步研究。反刍动物在采食习惯上具有天生的选择性,并且在某些情况下能够选择混合饲料中的某些成分,以最大限度提高自身的健康和生产力。研  相似文献   
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