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971.
The beta-galactosidase activity of the small intestinal mucosa of the neonatal dog has been studied over the pH range 3-0 - 5-8 using different substrates and in the presence and absence of p-chloromercuribenzoate. Partial separation of two beta-galactosidases has been achieved by gel filtration. The results suggest that three beta-galactosidases, comparable with those in other mammals, exist in canine small intestinal mucosa.  相似文献   
972.
973.
974.
1. The effect of diets with increasing concentrations of crude protein at either fixed essential amino acid concentrations or at fixed essential amino acid:dietary crude protein ratios on performance was examined in 1- to 4-week-old male Cobb chicks. Increasing crude protein intakes at constant essential amino acid concentrations was carried out at two dietary energy contents. 2. Increasing crude protein resulted in a linear decrease in feed intake while weight gain and feed efficiency changed quadratically with a smaller positive effect at the highest crude protein intakes. Feed intake decreased and feed efficiency increased with higher dietary energy and interactions between protein and energy were significant. Abdominal fat content and the efficiency of protein retention decreased with increasing dietary protein intake. 3. Using constant essential amino acid:crude protein ratios at increasing crude protein intakes resulted in (Trial 3) feed intake, weight gain and feed efficiency all increasing before reaching a plateau. Abdominal fat decreased with protein intake and the efficiency of protein retention was quadratic, decreasing at the higher protein intakes. 4. Multiple regression analysis of the results of the three trials indicated that partition of energy intake into maintenance, fat-free tissue growth, fat and the energy required to transform protein intake in excess of retention explained more than 98% of variation. 5. It is proposed that broiler performance at the lower protein intakes was limited by either non-essential amino acid (Trials 1 and 2) or essential amino acid (Trial 3) intake whereas at high protein intakes the decreased efficiency of amino acid utilisation after growth requirements are fulfilled resulted in poorer performance.  相似文献   
975.
To increase the production of sur karakul fur of the Surkhan Darya intrabreed type, regularities in the inheritance of colors in progeny have been studied. Both with homogeneous and heterogeneous breeding of ewes and stud rams of bronze, amber, and platinum colors, a high heredity of bronze and platinum colors is noted. The color of rams has a greater effect on inheritance of colors.  相似文献   
976.
In order to obtain data which will facilitate the scientific development of multiple intercropping of trees in agroforestry systems, the effects ofFaidherbia albida Del. orZiziphus spina-christi L. Desf. on soil quality and on yield of interplantedLeucaena leucocephala L. were investigated. The distance to which bothFaidherbia albida andZiziphus spinachristi trees improved soil quality as well asLeucaena leucocephala andSorghum vulgare L. production around them was about two times the radius of the tree crown. Higher yields of plants underZiziphus spina-christi thanFaidherbia albida were explained by similarly higher concentrations of available phosphorus (P). Other soil parameters, including total nitrogen (N), were similar under both species; being higher under the tree canopies than away from them. The study identified optimum tree spacing for agroforestry to be twice the tree crown radius. It also demonstrated the advantages of multiple tree mixtures over pure stands in improving soil quality and productivity.  相似文献   
977.
Objective— To determine if the receptor activator of nuclear factor-κB–receptor activator of nuclear factor-κB ligand–osteoprotegerin (RANK–RANKL–OPG) system is active in bone remodeling in dogs and, if so, whether differences in expression of these mediators occur in healthy and arthritic joints.
Study Design— Experimental study.
Sample Population— Fragmented processus coronoidei (n=20) were surgically removed from dogs with elbow arthritis and 5 corresponding healthy samples from dogs euthanatized for reasons other than elbow joint disease.
Methods— Bright-field immunohistochemistry and high-resolution fluorescence microscopy were used to investigate the distribution of RANK, RANKL, and OPG in healthy and arthritic joints.
Results— All 3 molecules were identified by immunostaining of canine bone tissue. In elbow dysplasia, the number of RANK-positive osteoclasts was increased. In their vicinity, cells expressing RANKL, a mediator of osteoclast activation, were abundant whereas the number of osteoblasts having the potential to limit osteoclastogenesis and bone resorption via OPG was few.
Conclusions— The RANK–RANKL–OPG system is active in bone remodeling in dogs. In elbow dysplasia, a surplus of molecules promoting osteoclastogenesis was evident and is indicative of an imbalance between the mediators regulating bone resorption and bone formation. Both OPG and neutralizing antibodies against RANKL have the potential to counterbalance bone resorption.
Clinical Relevance— Therapeutic use of neutralizing antibodies against RANKL to inhibit osteoclast activation warrants further investigation.  相似文献   
978.
枣庄市山亭区水泉镇下弯村的闫成民是当地首屈一指的养猪大户,2009年上半年他出栏肥猪300头,纯盈利4万元。但闫成民养猪不是一帆风顺的,是从失败中走出来的,是靠科学技术才发家致富的。  相似文献   
979.
Tuberculosis infections caused by Mycobacterium (M.) pinnipedii in a South American sea lion, Bactrian camel, and Malayan tapirs kept in two zoological gardens spanning a time period of 5 years are reported. The zoos were linked by the transfer of one tapir. Conventional bacteriological and molecular methods were applied to detect the pathogen. Spoligotyping and MIRU/VNTR-typing performed to assess the genetic similarity revealed identical molecular characteristics of the isolates from all animals involved. Anti-tuberculosis antibodies were detected using ELISA and a recently developed serological rapid test. The study shows that: (i) using molecular methods, the assessment of the genetic relationship of infectious agents helps to confirm the routes of infection, and that (ii) immunological tests may help to detect tuberculosis infections ante mortem more reliably and early. This would prevent the transfer of tuberculosis by asymptomatic animals.  相似文献   
980.
Spontaneous intoxication in 34 horses after ingesting freshly harvested maize that was to be used for ensiling and heavily contaminated with young Datura stramonium plants, is described. The clinical status of all horses was monitored for 7 days, and included body (rectal) temperature, respiratory and heart rates, colour and moistness of visible mucosae, changes in pupil size, appetite, thirst, general behaviour, locomotion, sensory perceptions, urination and defaecation. The intoxication was accompanied by altered clinical status, namely mild hyperthermia, tachycardia, polypnoea, dyspnoea and shallow breathing, mydriasis, dry oral, rectal, vaginal and nasal mucosae, acute gastric dilatation and severe intestinal gas accumulation, anorexia to complete refusal of feed, decreased or absent thirst, absence of defaecation and urination. As a result of the treatment, the clinical parameters normalised between days 2 and 5. Necropsies and pathological studies were performed on two horses that died, revealing toxic liver dystrophy, cardiac lesions and substantial dystrophic and necrotic processes in the kidneys. The observed clinical signs, the pathomorphological changes and the applied therapy could be used in the diagnosis, differential diagnosis, prognosis and treatment of Jimson weed intoxication.  相似文献   
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