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91.
本研究以4~8周龄的辽宁绒山羊母羔为研究对象,研究不同激素处理对羔羊卵泡发育数量和发育质量的影响,同时还比较了不同配方的培养液对羔羊卵母细胞体外成熟率的影响.结果表明:最佳的母羔超数排卵方案是依次注射PMSG 400 IU 1次,FSH(加拿大)40 mg 3次,间隔时间12 h;在成熟培养液中添加15%的发情羊血清(ESS)卵母细胞的体外成熟率最高.  相似文献   
92.
Between January, 2013 and December, 2014, there was a lumpy skin disease (LSD) outbreak that affected cattle in different localities of Zimbabwe. The outbreak resulted in severe economic losses to the livestock industry. A retrospective study was conducted by examining stored veterinary records of the LSD outbreak at the Central Veterinary Laboratory (CVL) in Harare, Zimbabwe. Over the 2-year period, a total of 10,038 cases and 880 deaths (8.77 %) were recorded. LSD was reported from all regions of the country, with the highest incidence occurring in Mashonaland West (30.95 %) and Midlands province (14.59 %). The frequency of reported outbreaks was highest in March and April, with the lowest reported cases occurring in November. A total of 25 representative specimens (skin biopsies) were collected from nodular skin lesions of infected cattle, and after viral DNA isolation, the P32 gene was successfully amplified, by using PCR, in 88 % (22/25) of all assayed specimens. Out of the 22 samples that showed amplification, 16 (73 %) were selected for DNA sequencing, and from these, 13 sequences were submitted to GenBank and assigned accession numbers: KX033494, KX033495, KX033496, KX033497, KXO33498, KX033499, KX033500, KX033501, KX033502, KX033503, KX033504, KX033505 and KX033506. Phylogenetic analyses of the 13 sequences was done by using MEGA 7 and showed that the viruses formed two major clusters implying that at least two strains of LSDV are in circulation in Zimbabwe. This study provides the first report on the incidence and molecular characterisation of LSDV in Zimbabwe.  相似文献   
93.
Forty-five Pelibuey sheep were experimentally infested with nematodes to evaluate the effect of three free condensed tannin (FCT) levels of Lysiloma acapulcensis on fecal egg counts (FECs), packed cell volumes (PCV), ocular mucosa colors (OMC), average daily gain (ADG), and adult nematode count. Five treatments were used: 12.5, 25.0, and 37.5 mg of FCT kg?1 of body weight (BW); sterile water (control); and ivermectine (0.22 mg kg?1 of BW) as chemical group. The data were processed through repeated measurement analysis. Even though the three FCT doses decreased (P?<?0.05) the FEC, the highest reduction was obtained with 37.5 mg kg?1 of BW. No differences were observed in PCV and OMC. Higher ADG (P?<?0.05) was observed with 37.5 mg kg?1 of BW of FCT. The count of adult nematodes (females and males) in the higher dose of FCT was similar to chemical treatment. Dose of 37.5 mg kg?1 of BW decreased the parasite infection and improved the lamb performance. Therefore, this dose could be used as a nutraceutic product in sheep production.  相似文献   
94.
This study was conducted to evaluate the feeding value of whole date palm (WDP) with and without enzyme supplementation on aged laying hen’s performance. Apparent metabolizable energy value of WDP was determined by the total collection method using ten adult leghorn cockerels. WDP was substituted with a corn-soybean meal basal diet at 40% level, and then the metabolizable energy of this experimental diet and basal diet was determined. After that, a total number of 256 Bovanz 95-week-old hens were randomly allocated into eight groups consisting of four replicates of eight birds each, based on a 4 × 2 factorial arrangement of the treatments. Eight iso-caloric and iso-nitrogenous experimental diets including one corn-soybean meal-based control diet and two, three, and four corn-soybean meal-based diets included 70, 140, and 210 g/kg ground WDP, respectively. Each of the diets supplemented with two levels of an enzyme (0.0 and 0.07 g/kg Natozim Plus). There was no significant difference in feed intake, feed conversion ratio, egg production, egg mass, eggshell thickness, and Haugh unit among the treatments (P > 0.05). However, yolk color score significantly decreased as dietary WDP level increased. The serum biochemical metabolites were not significantly affected by WDP and enzyme supplementation (P > 0.05). There were no significant differences in the relative weight of different organs except for abdominal fat. Our findings show that using WDP up to 21% of the diet was more economic and had no adverse effect on productive performance and serum metabolites of laying hens. However, WDP had an adverse effect on yolk color which can be ameliorated by carotenoid supplementation.  相似文献   
95.
Current status of resistance to benzimidazole (BZ) group of anthelmintic drugs against caprine nematodes in Central India at Amanala goat farm, Jabalpur, Madhya Pradesh (M. P.), was systematically investigated using faecal egg count reduction (FECR) test and egg hatch test (EHT). Besides, allele-specific PCR (AS-PCR) was deployed to ascertain the susceptible genotype (alleles) especially of the Haemonchus contortus. Randomly selected 30 goats, irrespective of age and sex, were divided into three groups of 10 each, to serve as treated and untreated controls. It was ensured that the animals were not administered with an anthelmintic drug for the past 3 months prior to undertaking the study, and faecal egg counts were estimated. FECR test evidenced fenbendazole resistance by partial elimination (24.90%) copro-egg counts in the treated group of animals vis-à-vis controls with a lower confidence interval of ?26%. Further, EHT revealed ED-50 value of 0.335 μg of thiabendazole/ml, confirming benzimidazole resistance in the animals of that farm. AS-PCR showed that 62% of H. contortus larvae were homozygous resistant (rr), 24% heterozygous (rS) and 14% homozygous susceptible (SS). The genotypic frequencies of three genotypes (rr, rS and SS) were significantly (P < 0.01) different. The prevalence of benzimidazole resistance allele (r) was also significantly (P < 0.01) higher (74%) as compared to susceptible allele (S) (26%). The resistance to benzimidazole has been discussed while emphasizing improved managemental practices designed to reduce exposure of the goat population to parasites, minimize frequency of anthelmintic use at optimum dose and rotational use of different chemical groups of medicines with different mode of action, so as to overcome and combat the upcoming problem in the field.  相似文献   
96.
A study was conducted to characterize the cattle production systems in Nyagatare District, Eastern Province of Rwanda using pre-tested questionnaires, interviews with key informants as well as focus group discussions in a period of 2 months. The respondents were selected by multi-stage sampling at sector and cell levels. Based on the procedure of Krejcie and Morgan (Educational and Psychological Measurement 30:607–610, 1970) to determine the overall sample size, the result indicated that the majority (98.3%) of farms were privately owned by large families of five to seven members, and most farmers (53.9%) had only primary education. Most respondents (52.6%) were in the age bracket of 41–50 years and were mainly (48.3%) located within 3 km from trading centers. The farm size averaged 6.5 ± 0.8 ha and most farms (64.7%) were fenced except in Rukomo Sector (50%) where zero grazing prevailed. Natural pastures (savanna grass land) were the main feed resource; tethering (9%) and communal grazing had diminished. Napier grass was the main planted forage (93.2%), followed by Chloris guyana (3.1%) and Brachiara (1.2%). Leguminous forages were rarely (2.5%) reported. Vita-mineral and salt block supplements, hay, and crop residues were the predominant supplementary feed stuffs used except in Karangazi and Rwemiyaga Sectors where only vita-mineral block predominated. However, maize and rice brans were reported to be the main feed stuffs used in supplementary feeding of lactating cows. Most farmers (89.7%) reported shortage of water as most of the farmers trekked their cattle to the nearest valley dams (59.2%), rivers (21.1%), and a few 6% had water on farms. Indigenous cattle were predominant (67.03%) followed by cross-breeds (28.37%) and exotics (4.6%) while all farmers kept small ruminants. Natural breeding predominated (74.9%) and most farms (60.6%) had animal houses most of which were temporary (52.8%). The reported mean age at first calving (AFC) was highest (40.2 ± .33) for Ankole and the lowest (29.1 ± .50) months for exotic cattle. Calving interval was shorter in local breeds than 65.7 ± 3.0 in exotic. The mean dairy milk yield was lowest for Ankole cattle 2.4 ± .08 as compared to the exotics (10.42 ± .36) and their crosses (7.2 ± .34). The main challenges were diseases, shortage of water, feeds, and inadequate extension services. Same observation was reported by Okello (African Journal of Range and Forage Science 22(3), 2005) in Uganda.  相似文献   
97.
Mesenchymal stem cells are undifferentiated cells that have the ability to divide continuously and tissue regeneration potential during the transplantation. Aging and loss of cell survival, is one of the main problems in cell therapy. Since the production of free radicals in the aging process is effective, the use of antioxidant compounds can help in scavenging free radicals and prevent the aging of cells. The aim of this study is evaluate the effects of L-carnitine (LC) on proliferation and aging of rat adipose tissue-derived mesenchymal stem cells (rADSC). rADSCs were isolated from inguinal region of 5 male Rattus rats. Oil red-O, alizarin red-S and toluidine blue staining were performed to evaluate the adipogenic, osteogenic and chondrogenic differentiation of rADSCs, respectively. Flow cytometric analysis was done for investigating the cell surface markers. The methyl thiazol tetrazolium (MTT) method was used to determine the cell proliferation of rADSCs following exposure to different concentrations of LC. rADSCs aging was evaluated by beta-galactosidase staining. The results showed significant proliferation of rADSCs 48 h after treatment with concentrations of 0.2 mM LC. In addition, in the presence of 0.2 mM LC, rADSCs appeared to be growing faster than control group and 0.2 mM LC supplementation could significantly decrease the population doubling time and aging of rADSCs. It seems that LC would be a good antioxidant to improve lifespan of rADSCs due to the decrease in aging.  相似文献   
98.
小尾寒羊泌乳期母羊能量需要量及代谢规律研究   总被引:4,自引:0,他引:4  
选择有代表性的小尾寒羊泌乳母羊6只,分成哺育单羔和双羔两组,每组3只,分泌乳前期(1~30天),泌乳中期(31~60天)和泌乳后期(61~90天)3个阶段进行饲养试验、消化代谢试验、呼吸测热试验及屠宰试验等研究。两组试羊均按NRC(1978)推荐的绵羊泌乳期哺育双羔母羊能量需要量供给代谢能和其它养分。结果表明,在本研究条件下,小尾寒羊泌乳母羊(包括哺育单、双羔者)在整个泌乳期内的平均日干物质(DM)、有机物质(OM)、代谢能(ME)和泌乳量分别为1689g,1571g,19.893MJ和653g。DM、OM和总能(GE)表观消化率分别为70.71%,72.58%和70.34%,代谢率(MEI/DEI)为84.89%。甲烷能占GEI的9.18%。每日畜体产热量(HP)为625.5KJ/kgW0.75。研究还表明:小尾寒羊泌乳母羊的每日维持代谢能和净能需要量分别为582.6和460KJ/kgW0.75,每户1kg原乳需要10802KJ的代谢能。维持效率为0.790泌乳效率为0.479,HI占GEI的18.10%。分析结果证明,试羊的泌乳量、采食量、畜体产热量和能量转化效率在单、双羔之间均无显著差异(P>0.05)。小尾寒羊泌乳母羊的代谢能总需要量(MER)可用下式估计:羊羔:MER=576.9W0.75+10810M;双羔:MER=588.2W0.75+10794M;平均:MER=582.6W0.75+1  相似文献   
99.
牛流行热的诊治   总被引:2,自引:0,他引:2  
自牛流行热在1976、1983、1987、1991年4次流行,据不完全统计我市发病牛达25万余头,死亡近千头,造成了巨大的经济损失。为有力地控制本病的流行,提高治愈率,我们采用中西结合治疗病牛37011头,收到了较好的效果。1 症状 该病有以下4个症候型。1.1 高热继发支气管肺炎型 主要表现为无食欲、发病急、体温高达42℃。病初表现为呼吸困难、气喘,呼吸80次/min左右。重者咳嗽,鼻内纤维蛋白渗出物增多,站立时头颈伸直,卧地困难,卧地时呼吸极度迫促,听诊呼吸音粗励。有干性或湿性罗音,心跳可达…  相似文献   
100.
选用6只小尾寒羊泌乳母羊,通过饲养试验、消化代谢试验、比较屠宰试验等手段,研究其蛋白质需要量。结果表明,小尾寒羊泌乳母羊代谢粪氮(MFN)和内源尿氮(EUN)的排出量分别为0.1312和0.13459/kg·W0.75·d。小尾寒羊泌乳期维持可消化粗蛋白需要量为1.51W0.75g/d,每产1kg奶需可消化粗蛋白829。小尾寒羊泌乳母羊的可消化粗蛋色总需要量(RDCP,g/d),可按下式求得:RDCP=1.51W0.75+82MP式中:W0.75——代谢体重,kg;MP——为产奶量,kg。  相似文献   
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