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1.
2年的牦牛放牧试验表明:除不同植物本身的生理特性外,降水和地温是影响小嵩草高寒草甸两季草场不同植物类群地上生物量绝对生长率的关键因素。小嵩草高寒草甸两季草场地上总生物量的绝对生长率1999年在7月份最大;1998年,冷季草场各放牧处理的绝对生长率在8月份达到最大,暖季草场的对照组和轻牧组在7月份最大,中牧组和重牧组在8月份最大。不同植物类群地上生物量生长率的变化不尽相同。1998年,冷季草场禾草和莎草地上生物量的绝对生长率8月份达到最大,暖季草场禾草和莎草地上生物量的绝对生长率7月份达到最大,且9月份出现了营养的再次积累;1999年,冷季草场禾草地上生物量的绝对生长率在6月份和8月份出现了两个峰值,暖季草场禾草地生物量的绝对生长率在7月份达到最大。对杂草类而言,1998年冷季草场的绝对生长率6月份最大,暖季草场重牧组的绝对生长率8月份达到最大,其他各处理7月份达到最大;1999年重牧组杂草的绝对生长率在6月份达到最大,其他各处理杂草在8月份达到最大。  相似文献   

2.
The prevalence of Cryptosporidium infection was examined in 480 healthy cattle (0-39 months old) in the Tokachi district in Hokkaido during the period from June to September in 2000 and from June to July in 2001. C. parvum oocysts were detected in 6 of 50 cattle (0-2 months old) in 2001; while C. muris was detected in 2 of 56 cattle (6-8 months old) in 2001, in 1 of 15 cattle (9-11 months old) in 2001, in 1 of 88 cattle (15-17 months old) in 2000, in 4 of 89 cattle (18-21 months old) in 2000 and in 2 of 53 cattle (21-23 months old) in 2000.  相似文献   

3.
柴达木绒山羊是在青海省有关部门重视支持下,业务单位历经26年的努力,于2009年底通过了国家品种委员会的审定。为使生产性能、体型外貌趋于一致,在新品种培育和巩固提高过程中采用了不同程度的近交。为了准确掌握该品种的近交程度,笔者对主产区核心群自1987年以来的系谱进行整理统计分析,现将结果报告如下:  相似文献   

4.
Related to its potential vulnerability the respiratory tract has a very complex and effective defence apparatus. The interaction between these defence mechanisms and certain characteristics of aetiological agents results in a pattern in which initial infections by these agents tend to occur at specific sites in the tract. Infections in which the primary portal of entry is in the upper respiratory tract include Bordetella bronchiseptica and Haemophilus spp in pigs; Pasteurella spp in cattle, sheep, pigs; Mycoplasma spp in cattle, sheep, pigs and poultry; equine herpesvirus 1 in horses; infectious bovine rhinotracheitis in cattle; parainfluenza 3 in cattle and sheep; infectious laryngo-tracheitis and infectious bronchitis in poultry; feline viral rhinotracheitis and calicivirus in cats; Aujeszky's disease virus and swine influenza in pigs; and equine influenza in horses. Infections in which the primary portal of entry is in the lower respiratory tract include Aspergillus fumigatus in poultry and mammals, respiratory syncytial virus in cattle, distemper virus in dogs and adenovirus in cattle and dogs. A fuller understanding of the interactions between an agent and the host at the point of entry would make it much easier to develop effective vaccines and therapeutic agents.  相似文献   

5.
Diarrhea in pigs has the potential to have a serious economic impact on the swine industry. Previously, we suggested that the likely cause of the presence of non-infectious diarrhea in pigs characterized by lactate accumulation was dyspepsia. In this experiment, the prevalence of enteropathogens and hyper-lactate accumulation in feces of piglets in 4 distinct growth stages was examined. The feces were collected when veterinarian experts recognized abnormalities in sporadic outbreaks. Prevalence of enteropathogens in diarrheal feces was 100% in fattening pigs (FP), 75% in weaning pigs (WP), 50% in suckling pigs (SP), and 42% in growing pigs (GP). Prevalence of enteropathogens in loose feces was 53% in WP, 50% in SP, 40% in FP, and 28% in GP. Prevalence of hyper-lactate accumulation in diarrheal feces was 33% in GP, 33% in SP, 25% in WP, and 25% in FP. Prevalence of hyper-lactate accumulation in loose feces was 40% in GP, 0% in SP, 7% in WP, and 5% in FP. Accordingly, non-infectious dyspepsia is frequent in growing pigs. In this period, pigs are potentially exposed to needless antimicrobial therapeutic treatments in sporadic cases.  相似文献   

6.
Different experimental systems are used to study developmental processes in mammals. In this study, three experimental models were analysed and correlated: (1) cultivation of rat embryos in vitro; (2) cultivation in vitro and then transplantation in vivo; (3) direct transplantation in vivo. When embryos were cultivated in vitro and then transplanted in vivo, after the initial in vitro restriction, developmental potential was recovered. The in vitro restriction depended on medium used and duration of culture. Pre-cultivation in serum-free medium for 7 days restricted developmental potential for nervous tissue, and for 14 days restricted developmental potential for skeletal muscles, adipose tissue and glandular epithelia. Transferrin addition improved in vitro differentiation of neuroblasts, cartilage and columnar epithelium. In the combined in vitro and in vivo method, transferrin preserved developmental potential in comparable extent to the addition of the serum. Even in serum-free conditions in vitro, the subsequent in vivo wide expression of developmental potential was possible. Therefore, the combination of in vitro and in vivo methods turned to be advantageous than the isolated approaches (in vitro or in vivo only), and enabled testing in more detail the influence of a single substance on developmental course and potential.  相似文献   

7.
The concentration of ascorbic acid in the cerebrum and in the brain stem of bovine fetuses decreased with increasing body weight; in the cerebellum there was no change. The decrease of the concentration in the lungs, in the heart, in the kidneys, in the M. longissimus and in the M. semimembranosus in the course of the fetal growth was different. In the liver and in the adrenals the concentration in the 3 groups of fetuses with a body weight of 4.18 +/- 2.01, of 9.72 +/- 0.97 and of 17.12 +/- 2.61 kg was similar. The highest concentrations were found in the adrenals, in the testes and in the cerebrum. The functional significance of the changes in the concentration in the tissues of the bovine fetuses is discussed and compared with the results in human fetuses and in adult cattle.  相似文献   

8.
After intravenous administration of theophylline, microdialysis has been used for studying the non protein bound theophylline concentration in blood and in lung tissue in the rat as well as in two horses. The distribution pattern of 14C-theophylline in the rat was also investigated. When the distribution of theophylline was completed the time course of free drug in the interstitial fluid in lung tissue was in good agreement with the total concentration-time profile in plasma in both species. In the rat the free concentration of theophylline in the lung was slightly lower than the free concentration in the blood from 40 to 300 min. The in vivo protein binding in blood was 48.8 +/- 6.2% in the rats (n = 9) and 8-25% in the horses (n = 2). The whole body autoradiography study in rat showed that the concentration of radioactivity in the lung followed the blood concentration very closely up to 24 h after injection. The effect of theophylline in the lung can be assumed to be related to the plasma concentration of theophylline, since the concentration-time profile in plasma reflects the time course in the lung.  相似文献   

9.
奶牛发情周期中毛 唾液和乳汁孕酮水平的变化   总被引:1,自引:0,他引:1  
本实验采用放射免疫分析法(RIA)测定了11头奶牛一个发情周期里毛、唾液、乳汁中孕酮(P_4)含量。经产牛(n=8)的毛和唾液中P_4水平变化与乳汁中P_4水平变化一致。青年牛(n=3)的毛和睡液中的P_4水平变化一致,并分别与经产牛毛和唾液中P_4水平变化一致。7头配种后的经产牛和5头配种后的青年牛分别取20和23天的样品进行妊娠诊断,与配种后60天的直检结果相对照,依据经产牛毛、乳P_4水平进行妊娠诊断的阳性准确率分别是85.7%(6/7)和100%(7/7),依据青年牛毛P_4水平进行妊娠诊断的阳性准确率为100%(5/5)。  相似文献   

10.
Antimicrobial growth promoters (AGPs) were phased out in Denmark, Norway and Sweden in 1998-1999, 1995 and 1986, respectively. The annual usage of therapeutic antimicrobials in animals in Denmark almost doubled during the period when AGPs were phased out (1988-1999) and in the subsequent 2 years. The increase was mainly due to an increased consumption of therapeutic antimicrobials in weaning pigs. The annual increase in usage of therapeutic antimicrobials and the annual increase in numbers of slaughter-swine produced in Denmark correlates well, except for 1999 when AGP use was discontinued in weaning pigs, and the following year. In Norway, the usage of therapeutic antimicrobials in animals decreased by 39% from 1995 to 2000. During 2001-2003 the annual usage remained at the 2000-level. The annual numbers of slaughter-swine produced in Norway increased gradually by 10% after the AGP discontinuation (from 1995 to 2003). In Sweden, the usage of therapeutic antimicrobials in animals increased by 21% the first 2 years subsequent to the AGP ban (1986-1988), remained then constant until 1994; from 1994 to 2003 this usage declined by 47%. The initial increase was caused by increased use in broilers and in weaning piglets. The amounts used in animals in Sweden in 2003 were half of the amounts used in 1994. The annual numbers of slaughter-swine produced in Sweden declined gradually by 16% in the study period, although fluctuating. In Denmark, Norway and Sweden the number of dairy cattle and beef cattle declined only slightly in the various study periods while numbers of broilers produced increased notably, especially in Norway and Sweden. Following the termination of AGPs the total usage of antimicrobials (AGPs and therapeutic antimicrobials) in animals in Denmark declined 36% (from 1996 to 2003): in Norway this figure was 45% (from 1995 to 2003). In Sweden, the total usage of antimicrobials in animals in 2003 amounted to only one third of the amounts used in 1984 (decreased from 51 to 16 tonnes). Termination of AGPs was only a temporary risk factor for increased usage of therapeutic antimicrobials in food-animals in Sweden and Denmark; however, an exception might be usage in weaning piglets in Denmark. Furthermore, the discontinuation of AGP use has decreased the overall annual usage of antimicrobials in animals in Denmark, Norway and Sweden considerably.  相似文献   

11.
A study was undertaken to investigate the effect of immunosuppression by cyclophosphamide or methylprednisolone on the clinicopathological alterations in respiratory absidiosis in rabbits. Infected rabbits showed respiratory distress that was more severe in immunosuppressed groups. Leukocytosis due to neutrophilia was observed in the non-immunosuppressed group in the initial stages, whereas leukopenia was observed in both the immunosuppressed groups initially, owing to polymorphopenia in the cyclophosphamide-treated group and to lymphopenia in the methylprednisolone-treated group, followed by leukocytosis in both groups. Total serum proteins increased significantly in the non-immunosuppressed group but were significantly decreased in the immunosuppressed groups. Serum creatinine increased significantly in all the infected groups from 20 days post inoculation (DPI) onwards. Blood urea nitrogen increased significantly in the initial stages only in the methylprednisolone-treated group. AST and ALT also showed significant increases in the infected animals. Total serum immunoglobulins and circulating immune complexes increased gradually in all three infected groups, except for an initial significant drop in the immunosuppressed rabbits. Re-isolation of fungus was only achieved from the lungs of infected rabbits up to 15 DPI in the non-immunosuppressed group and 30 DPI in the immunosuppressed groups. Pathological lesions in all the infected groups were found mainly in the lungs and consisted of pyogranulomas. The lesions were most severe in the cyclophosphamide-treated group and least severe in the non-immunosuppressed group.  相似文献   

12.
Roger Marshall was born in Christchurch on 27 May 1933 and died at his home in Palmerston North on 24 October 2001. He graduated BVSc from the University of Sydney in 1958 and began his professional career in clinical veterinary practice in Morrinsville. Wishing to specialise in veterinary microbiology, he later enrolled in the postgraduate course for the Diploma in Microbiology at the University of Otago under Professor JAR Miles. On gaining the Diploma in 1963, Roger was appointed a foundation lecturer in veterinary microbiology in the newly formed Faculty of Veterinary Science at Massey University.  相似文献   

13.
Immunohistochemical study of osteopontin in boar testis   总被引:3,自引:0,他引:3  
The expression of osteopontin (OPN) in boar testis was studied. Western blot analysis detected 66- and 32-kDa OPN immunopositive bands in the testes of adult boars. In postnatal piglets, the 66-kDa OPN band was detected in the testes, but not the 32-kDa band. In the newborn testis, OPN immunostaining was seen in gonocytes and in some supporting cells in the seminiferous tubules, as well as in interstitial Leydig cells. In the adult boar testis, OPN immunoreactivity was detected in seminiferous tubules with varying intensities. Intense OPN immunostaining was seen in the residual bodies and acrosomes in the spermatids while, occasionally, OPN immunostaining was seen in spermatogonia and various stage of spermatocytes but in few Sertoli cells in the seminiferous tubules. In addition, Leydig cells in adult boars were weakly immunostained with OPN. These findings suggest that OPN is detected in the majority of germ cells and is involved in spermatogenesis in boar testis.  相似文献   

14.
The study was conducted to detect the indoor environmental quality parameters of broiler house with three-overlap cages and analyze the differences in winter and autumn. In the process of feeding, the same farming house in the same farm was chosen to carry out the test. The indoor ambient temperature, humidity and the air quality were determined in chicken house in different seasons. The measure points were distributed in 4 different positions in the house. The experiment period was from 3 to 6 weeks of broilers.The results showed that there was no significant difference in the ambient temperature between autumn and winter during experimental period (P >0.05). The ambient temperature in the house in winter was slightly higher than in autumn. The humidity in autumn was significantly higher than that in winter (P <0.05).The temperature and humidity in two seasons could meet the requirements of broiler growth. There was no significant difference in ammonia concentration between autumn and winter, while ammonia level in winter was slightly higher than that in autumn. The carbon dioxide in the house was significantly higher in winter than that in autumn (P <0.05). The total number of airborne bacteria in winter was significantly higher than that in autumn (P <0.05). The indoor temperature kept constant in autumn and winter seasons in closed poultry house. In winter, the humidity was reduced, the carbon dioxide concentration was increased, and the total number of bacteria in the air was increased.So, the ventilation should increase at the same time of heating in winter.  相似文献   

15.
The structure and fill of the omasum was investigated in summer and in winter in adult female reindeer living on the polar desert and tundra of the high Arctic archipelago of Svalbard and in sub-Arctic mountain habitats in northern Norway. The mean total mass of the omasum in non-lactating adult female Svalbard reindeer was 467 g (0.65 g per 100 g live body mass (BM)) in September and 477 g (1.03 g per 100 g BM) in April. By contrast, the mean mass of the omasum in non-lactating adult reindeer in northern Norway was 534 g (0.83 g per 100 g BM) in September but only 205 g (0.35 g per 100 g BM p < 0.05) in late March, owing to a decrease in both tissue mass and the wet mass of the contents of the organ. The mean absorptive surface of the omasum in Svalbard reindeer was 2300 cm2 in September and 2023 cm2 in April. In Norwegian reindeer, by contrast, the absorptive surface area decreased from 2201 cm2 in September to 1181 cm2 (p < 0.05) in late March. The marked seasonal decline of omasal tissue and contents in Norwegian reindeer probably results from intake of highly digestible forage plants, including lichens, in winter. Svalbard reindeer, a non-migratory sub-species, survive eating poor quality fibrous vascular plants in winter. The absence of any marked seasonal change in the mass, total absorptive surface area or filling of the omasum in Svalbard reindeer in winter despite a substantial decline in body mass presumably reflects their need to maintain maximum absorption of nutrients, including volatile fatty acids, when feeding on such poorly fermentable forage.  相似文献   

16.
Campylobacter spp. have been identified as etiologic agents in outbreaks and sporadic cases of gastroenteritis in developed countries. In developing countries, most reported Campylobacter infections are in children. Previously reported prevalences of Campylobacter spp. in children in Southeast Asia range from 2.9% to 15%. The frequency and pattern of occurrence of Campylobacter spp. differ between developed and developing countries, especially in the number of cases reported in adults and the presence of any seasonal patterns in occurrence. Although the severity of Campylobacter infection in adults was different between developed and developing countries, the clinical symptoms of infection in adults resulting from infection in developing countries was similar to those in developed countries. Many different animal species maintain Campylobacter spp. with no clinical signs. There do not appear to be significantly different colonization rates of Campylobacter in food animals between developed and developing countries. The role of C. jejuni as a primary pathogen in farm animals is uncertain. C. jejuni can be found in feces of diarrheic and healthy calves and piglets. Campylobacter with resistance to antimicrobial agents have been reported in both developed and developing countries, and the situation seems to deteriorate more rapidly in developing countries, where there is widespread and uncontrolled use of antibiotics resistance was observed at high levels in food animals in both developed and developing countries. Studies suggested an association between antimicrobial use in food animals and the development of resistance in human isolates in developed countries.  相似文献   

17.
Diseases of the respiratory tract commonly occur in captive chelonians, and several diseases also have occurred in wild chelonians. Infectious causes include viruses, bacteria, fungi, and parasites. Herpesviruses have surfaced as important pathogens of the oral cavity and respiratory tract in Hermann's tortoise (Testudo hermanii), spur-thighed tortoise (Testudo graeca), and other tortoises in Europe and the United States. Herpesvirus-associated respiratory diseases also have been reported in the green turtle, Chelonia mydas, in mariculture in the Cayman Islands. Of diseases caused by bacteria, an upper respiratory tract disease caused by Mycoplasma sp has been reported in free-hanging and captive gopher tortoises in the southeastern United States and in desert tortoises in the Mojave Desert of the southwestern United States. Mycotic pulmonary disease is commonly reported in captive chelonians, especially in those maintained at suboptimal temperatures. An intranuclear coccidia has been seen in several species of captive tortoises in the United States, and, in one case, a severe proliferative pneumonia was associated with organisms in the lung. The most common noninfectious cause of respiratory disease in chelonians results from trauma to the carapace. Although pulmonary fibromas commonly occur in green turtles with fibropapillomatosis, for the most part, tumors of the respiratory tract are uncommon in chelonians.  相似文献   

18.
In 15 selected stocks in the Strakonice district, 507 slaughter pigs, 708 small terrestric mammals and 110 free-living birds were examined in a two-year period (1986-1987) to study the occurrence of carriers of yersiniae and their elimination. Rectal smears from 243 persons working in livestock production were examined in the same way. Standard bacteriological methods, recent examination procedures (Aulisio et al., 1980; Aldová, 1981) and a diagnostic antiserum (03 IMUNA Sarisské Michalany) were used for the examination. The following results were obtained: In pigs: 1. yersiniae were detected in 65 cases (12.8%); of this, in 31 cases they occurred in the tonsils, in 35 cases in ileum, and twice in the ileocaecal lymph nodes. 2. Epidemiologically significant Y. enterocolitica 4;03 was detected in 28 cases (5.5%); of this, 22 times in the tonsils, 7 times in ileum, and once in the ileocaecal lymph nodes. 3. The seasonal nature of the occurrence of yersiniae was confirmed in 1986, with maxima in winter-spring, but in 1987 their occurrence declined substantially to less than a quarter. In the small mammals, yersiniae were detected 28 times (4%); of this, 7 times in common field mouse, 11 times in common vole, 5 times in house mouse, twice in shrew, once in Apodemus flavicollis, and once in Apodemus sp. 2. Y. enterocolitica 4;03 was detected twice (0.26%), both cases in the house mouse. Other results: 1. In all the 110 free-living birds the examination for yersiniae had a negative result; 2. in the rectal smears of 243 persons employed in livestock production, yersiniae were identified twice (0.8%)--in one case Y. enterocolitica 1, in the other Y. enterocolitica biovars 1 and 2.  相似文献   

19.
对青海省三角城种羊场夏(六月中旬)、秋(九月中旬)、冬(十二月中旬)三季的水、土壤、牧草、绵羊被毛、血液、组织器官中铁含量进行了调查与测定分析。结果表明,三季土壤铁均处于丰盈状态;牧草中铁夏季>秋季>冬季,且含量较高;绵羊被毛中三季铁含量也处于正常范围之内,三季血液、肝脏中的铁充足。从整个土壤-牧草-畜体生态体系来看,青海三角城种羊场绵羊处于铁充足的营养状况。  相似文献   

20.
Pituitary and serum from 86 male or female horses of various reproductive states were collected in the normal breeding season (summer) and in the nonbreeding season (winter) at a commercial slaughterhouse. Concentrations of prolactin (PRL), luteinizing hormone (LH) and follicle stimulating hormone (FSH) were measured by radioimmunoassay. Concentrations of pregnant mare serum gonadotropin and reproductive steroids in serum and gross appearance of the reproductive tract and gonads were used to catagorize reproductive state. Concentrations of PRL were higher (P less than .01) in summer than in winter in pituitary and serum of mares, stallions and geldings. In summer, mares had higher (P less than .01) concentrations of PRL in serum than stallions. In mares, concentrations of LH in pituitary were higher (P less than .05) in summer than in winter. Concentrations of LH in serum were higher (P less than .01) in summer than in winter in mares and geldings, higher (P less than .01) in mares than in stallions in summer, higher (P less than .01) in geldings than in stallions in summer and higher (P less than .01) in mares with low serum progesterone (P) concentrations than in mares with high P concentrations in summer. Concentrations of FSH in pituitary and serum did not differ between summer and winter for any type of horse.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

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