共查询到20条相似文献，搜索用时 31 毫秒
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《African Zoology》2013,48(1):117-124
A preliminary investigation of the diversity and density of small mammals in four structurally distinct habitat types in an actively-utilized farming landscape was carried out. We sought to understand how diversity and density are influenced by landscape structure, habitat structure and management decisions. Farmers in the area believe small mammals provide a service as an alternative food source, other than sheep, for predators. We assessed the validity of this reported ecosystem service. A total of 10 species and 219 individuals were recorded during this survey of 3600 trap-nights, with a total trap success rate of 6.1%. Significantly more individuals were caught during the winter than in summer. Vegetation transformation had a negative impact on small mammal diversity. Density, diversity and distribution were correlated with vegetation and landscape structural diversity. Management decisions that reduce vegetation structure and cover will have a negative impact on small mammal density and diversity. Ensuring the conservation of small mammals may have the benefit of providing an alternative food source to predators, a valuable ecosystem service to farmers. 相似文献
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Selecting 6 heads of new yak strains(the offspring of reciprocal cross of F1 produced by wild yak male mated with domestic yak female)and 6 domestic yaks at 3 and 12 age in months respectively at Datong Yak Farm of Qinghai Province. This paper was studied for the morphological characteristics of the skin and hair coat of yak and their adaptability to the cold living environment in Qinghai-Tibetan plateau. The results indicated that it should be of vital importance marker for the morphological characteristics of the skin and hair coat with two type of yaks at 3 and 12 age in months and their regulations of growth and development to adapt to the cold living environment in Qinghai-Tibetan plateau,The main morphological indexes of the skin and hair coat of the rearing new yak strain were higher than those of the domestic yaks at the same age in months, or speak precisely, the new yak strain was more powerful adaptable to the alpine cold living environment than that of the domestic yaks. The resvlts above provided scientific basis for the native strain breeding of yak and the new yak strain rearing. 相似文献
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YU Zuhua DING Ke JIA Yanyan YU Chuan HE Lei LIAO Chengshui LI Jing ZHANG Chunjie LI Yinju WU Tingcai CHENG Xiangchao MENG Kaikai ZHANG Jin YU Zuling ZHOU Ziyu LUO Jun 《畜牧兽医学报》1956,51(10):2567-2575
This study aimed to detect the effect of Gallus TGFβ1 on the biological behavior of MDCC-MSB1 cells. MDCC-MSB1 cells were transiently transfected with Gallus TGFβ1 overexpression vector, interference expression vector, and the corresponding negative control. Then, the expression of Gallus TGFβ1, the cell proliferation, the cell cycle and apoptosis, the migration and invasion of each transfection groups were examined. Results showed that compared with the corresponding control, the MDCC-MSB1 cells transfected with overexpression vector of Gallus TGFβ1 could up-regulate the expression level of TGFβ1, the proliferation of MDCC-MSB1 cells was significantly inhibited, G1 phase cells were increased, S and G2 cells were decreased, the apoptosis rate of the cells was increased, the migration and invasion ability were decreased.However,the MDCC-MSB1 cells transfected with the interference expression vector of TGFβ1 significantly down-regulated the expression level of TGFβ1, cell proliferation was improved,G1 phase cells were decreased, S and G2 cells were increased, the cell apoptosis was decreased, the migration and invasion ability was increased. The results showed that Gallus TGFβ1 could inhibit the proliferation, migration and invasion of MDCC-MSB1 cells, and promote their apoptosis. 相似文献
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William H. Romme Craig D. Allen John D. Bailey William L. Baker Brandon T. Bestelmeyer Peter M. Brown Karen S. Eisenhart M. Lisa Floyd David W. Huffman Brian F. Jacobs Richard F. Miller Esteban H. Muldavin Thomas W. Swetnam Robin J. Tausch Peter J. Weisberg 《Strength and Conditioning Journal》2009,62(3):203-222
Piñon–juniper is a major vegetation type in western North America. Effective management of these ecosystems has been hindered by inadequate understanding of 1) the variability in ecosystem structure and ecological processes that exists among the diverse combinations of piñons, junipers, and associated shrubs, herbs, and soil organisms; 2) the prehistoric and historic disturbance regimes; and 3) the mechanisms driving changes in vegetation structure and composition during the past 150 yr. This article summarizes what we know (and don't know) about three fundamentally different kinds of piñon–juniper vegetation. Persistent woodlands are found where local soils, climate, and disturbance regimes are favorable for piñon, juniper, or a mix of both; fires have always been infrequent in these woodlands. Piñon–juniper savannas are found where local soils and climate are suitable for both trees and grasses; it is logical that low-severity fires may have maintained low tree densities before disruption of fire regimes following Euro-American settlement, but information is insufficient to support any confident statements about historical disturbance regimes in these savannas. Wooded shrublands are found where local soils and climate support a shrub community, but trees can increase during moist climatic conditions and periods without disturbance and decrease during droughts and following disturbance. Dramatic increases in tree density have occurred in portions of all three types of piñon–juniper vegetation, although equally dramatic mortality events have also occurred in some areas. The potential mechanisms driving increases in tree density—such as recovery from past disturbance, natural range expansion, livestock grazing, fire exclusion, climatic variability, and CO2 fertilization—generally have not received enough empirical or experimental investigation to predict which is most important in any given location. The intent of this synthesis is 1) to provide a source of information for managers and policy makers; and 2) to stimulate researchers to address the most important unanswered questions. 相似文献
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This paper was carried out on the morphological character of the test and epididymis of three types of yak bull age 6,12,18,24 months old (1/2 wild yak, cross 1/2 wild yak and domestic yak). The results showed that the weight and size of testes and epidiymis was increased with the age which was hardly affected by imbalance of food supply during the cold and warm seasons. The development were similar for three kinds of yak at the same age(P＞0.05). 相似文献
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Veterinary Research Communications - 相似文献
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G.T. Williamson M.R.C.V.S. 《New Zealand veterinary journal》2013,61(4):75-76
Extract “Enterol” (I.C.I.) was first used in a moribund pig with rather astonishing results. From the symptoms described, it was presumed that it had salmonellosis. As a result of this observation, the writer was asked to try the drug on known salmonellosis cases. 相似文献
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1. Growth rate, laying traits, food intake and food conversion efficiency of laying hens were compared in several experiments on pairs of full or half sibs one of which was a pea‐comb bird (Pp), the other single‐comb (pp).
2. There was a slight but significant depressing effect associated with the Pp genotype on 8‐week weight of chicks and body weight of laying hens in some populations.
3. Pea‐comb hens showed a reduction of about 2% in food consumption, independent of the effects on body weight and egg production, and we suggest that with the smaller size of comb and wattles for Pp hens, heat losses and hence energy requirements are less.
4. Appetite seemed to be more depressed at high ambient temperature in birds of the Pp genotype. 相似文献
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Traditionally and when using objective gait analysis, horses with and without lameness are most frequently assessed trotting in straight lines in hand. Valuable information can be gained from assessment on the lunge and ridden in walk, trot and canter. No studies have quantified lameness during all aforementioned conditions and gaits at once, despite the rapid recent development in equine gait analysis methods. Objective methodologies, previously confined to gait laboratories, are currently being expanded to field technologies using accelerometers and inertial measurement units (IMUs). This publication aims to describe normal gait and the spectrum of pain-related gait abnormalities and other musculoskeletal adaptations to pain that can be observed in walk, trot and canter during in hand and ridden assessment in straight lines and on a circle on hard and soft surfaces. In addition, it aims to describe briefly how IMUs have been used and areas for further research in the light of what we know from subjective lameness examinations and what is possible with IMUs. 相似文献
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《动物营养（英文）》2019,5(3):217-226
Dietary fibers (DF) contain an abundant amount of energy, although the mammalian genome does not encode most of the enzymes required to degrade them. However, a mutual dependence is developed between the host and symbiotic microbes, which has the potential to extract the energy present in these DF. Dietary fibers escape digestion in the foregut and are fermented in the hindgut, producing short-chain fatty acids (SCFA) that alter the microbial ecology in the gastrointestinal tract (GIT) of pigs. Most of the carbohydrates are fermented in the proximal part, allowing protein fermentation in the distal part, resulting in colonic diseases. The structures of resistant starch (RS), arabinoxylan (AX), and β-glucan (βG) are complex; hence, makes their way into the hindgut where these are fermented and provide energy substrates for the colonic epithelial cells. Different microbes have different preferences of binding to different substrates. The RS, AX and βG act as a unique substrate for the microbes and modify the relative composition of the gut microbial community. The granule dimension and surface area of each substrate are different, which influences the penetration capacity of microbes. Arabinose and xylan are 2 different hemicelluloses, but arabinose is substituted on the xylan backbone and occurs in the form of AX. Fermentation of xylan produces butyrate primarily in the small intestine, whereas arabinose produces butyrate in the large intestine. Types of RS and forms of βG also exert beneficial effects by producing different metabolites and modulating the intestinal microbiota. Therefore, it is important to have information of different types of RS, AX and βG and their roles in microbial modulation to get the optimum benefits of fiber fermentation in the gut. This review provides relevant information on the similarities and differences that exist in the way RS, AX, and βG are fermented, and their positive and negative effects on SCFA production and gut microbial ecology of pigs. These insights will help nutritionists to develop dietary strategies that can modulate specific SCFA production and promote beneficial microbiota in the GIT of swine. 相似文献
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Biosecurity compliance is an issue in all types of animal production. Poor compliance is frequently related to lack of knowledge or comprehension. Human dimensions, such as personality and attitudes were also suggested as being related to compliance. As part of a larger study, personality traits, experience, education and training of employees, visitors and growers were evaluated to assess their relationship with their compliance with biosecurity measures when entering and exiting poultry barns. Biosecurity compliance was evaluated using hidden cameras. One hundred fourteen individuals involved in a total of 2379 visits on 23 poultry farms responded to a personality test. Results demonstrated that several determinants of compliance exist, and some are related to personality, experience and education. Three personality traits were significantly associated with compliance: responsibility, complexity and action-oriented. Such information has important implications for the selection of job applicants or task attribution and to enhance effectiveness of training programs. 相似文献
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Abstract The aim of this study was to evaluate the effect of Mentha piperita L. (MP) dried leaves on the in vitro rumen methanogenesis and fermentation. It was found that after 24 hours of incubations, addition of 16.34 and 23.35 mg of MP to the 233.3 mg of substrate significantly decreased methane emission by 41.52 and 15.51%, respectively. Simultaneously, the MP supplementation exerted no effect on the dry matter digestibility and volatile fatty acid profile. Addition of MP to the ruminants' diet inhibits the methane production without altering the basic parameters of rumen fermentation. 相似文献
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1. The present study was conducted to determine the possibility of using low‐protein broiler diets supplemented with synthetic amino acids. The effects on performance, carcase composition and nitrogen retention were evaluated.)
2. A starter diet was given, ad libitum, from 7 to 21 and a finisher diet from 21 to 42 d of age. Body weight, weight gain, food intake and food conversion (FC) were determined at 3 and 6 weeks of age. Abdominal fat deposition (AFD), carcase yield, carcase fat and protein and nitrogen retention were determined at 6 weeks of age. During the starter period chicks were given a 231 g/kg crude protein (CP) diet and a low protein diet supplemented with synthetic amino acid, a: to National Research Council recommendations, b: to the concentration of the control diet, and c: in agreement with the pattern of body composition. Glutamic acid and glycine were added to some diets as sources of non‐essential amino acids (NEAA). All diets contained 12.62 MJ metabolisable energy (AMEn)/kg. The diets administered between 3 and 6 weeks were comparable to the starter diets, except that they contained more AMEn (12.85 MJ/kg) and less protein.
3. Performance equal to that of high protein controls was obtained with birds fed a low protein diet supplemented with synthetic essential and NEAA to the amounts in the control diet or based on the amino acid profile of body protein. This was not achieved with low protein diets supplemented with synthetic amino acids to the amounts recommended by NRC.
4. Without altering performances, the efficiency of protein utilisation of birds fed on low protein diets was superior to that of birds fed on the commercial control diet and their nitrogen excretion was reduced by 26%. The percentage carcase yield and protein was unaffected by the dietary regimen but carcase fat content and AFD increased as the protein content of the diet decreased.
5. These results show that it is possible to obtain the same performances with low protein diets supplemented with synthetic amino acids, using an ideal amino acid balance. However, low protein diets result in a higher carcase fat content. 相似文献