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61.
Sixty‐four nulliparous female rabbits were distributed among eight groups (eight animals/group). Group one was the unsupplemented control group; the other seven groups were supplemented with zinc bacitracin (ZnB) at 100 mg, or bee pollen (BP) and/or propolis (Pro) at 150 and 300 mg in a capsulated form, three times a week, day after day, continuously all over the experimental period. The experiment was run for eight parties; at each parity, 28 kids of each doe group (a total of 224 rabbits) were divided into two subgroups weaned, respectively, at 24 and 30 days of age. Thus, for each parity, there were 16 groups (eight does treatments × two weaning age, 14 rabbits per group). The growing rabbits fed the standard diets without supplements. The growth performance, the carcass traits, the liver and the spleen histology of rabbits were checked up to 90 days of age to find possible carryover effects of the supplements. The supplements had no significant effect on most of the growth performance at 90 days of age, but BP150 and BP+Pro300 increased the growth rate in comparison with ZnB group. The liver weight in the control, BP300 and Pro300 groups was higher than the ZnB one. The spleen weight was higher in the groups ZnB, BP150, Pro300 and BP+Pro300, followed by the control, BP300 and BP+Pro150 and thus Pro150. The heart % in the BP150 and Pro300 groups was higher than ZnB and BP+Pro150 groups. A lymphoid hyperplasia of splenic white pulp was observed in the BP+Pro groups, while propolis alone showed a mild activation of lymphobiosis. The Pro and BP groups showed the same picture of the control group exhibiting a hydropic degeneration of mostly hepatic cells, while the ZnB group exhibited adverse effect on the bile ducts featuring portal periductal inflammatory cells infiltration with epithelial hyperplasia reflecting chronic cholangitis.  相似文献   
62.
Heavy metals have enormous variety of deleterious effects on many organs in the body. This study demonstrated the toxic influences of lead on the growth, biochemical, cellular and molecular aspects of developing rabbits. Seventy‐five rabbits (New Zealand NZW) were divided into five equal groups as follows; control (C) and four treatment groups (T1‐4) orally administered lead acetate solution as follow T1: 20, T2: 30, T3: 50 and T4: 70 mg/kg body weight. Lead resulted in a significant decrease in live body weight, daily body weight gain and feed intake in T3 and T4 compared to those in other groups. Blood haematology measurements such as red blood cells, haematocrit (HCT), mean corpuscular volume, platelet, white blood cells and lymphocytes were significantly influenced by the high level of lead. Oral administration of lead significantly reduced total proteins in the serum. It was observed that the high lead level led to significantly (p < 0.05) increased levels of aspartate aminotransferase, alanine aminotransferase enzymes, urea and creatinine. Four random amplified polymorphic DNA primers polymorphism were detected among the treatment groups. Total number of induced bands (loss or appearance) compared with control group were 4, 10, 10 and 14 bands using primers P1, P2, P3 and P4 respectively. Number of micronuclei showed a dose–response increase and the difference was highly significant especially between control compared with T3 and T4 groups. From our results, we can conclude that exposure of rabbits to lead acetate resulted in negative effects on the growth performance and altered the haematological and biochemical parameters, in addition to its adverse impact on cytological and molecular characterization of animals.  相似文献   
63.
Mutations in the β‐carotene oxygenase 2 (BCO2) gene can impair the function of the enzyme that breaks down carotenoids. As a result, gradual accumulation of unoxidized carotenoids in animal tissues gives them a yellow colour. The aim of the study was to determine the content of carotenoids, retinol and α‐tocopherol in the liver, fat and milk of rabbit does with three different genotypes determined by AAT‐deletion mutation at codon 248 of the BCO2 gene and to find out whether differences in the concentrations of the above compounds in the tissues and milk of the does affect reproduction parameters and the rearing rate of kittens. The experimental materials comprised 36 does, 12 of each genotype of the BCO2 gene, with their litters. Females with their litters were placed in individual cages, on deep litter. Between days 7 and 13 of lactation, samples of milk were collected from the does. The kittens stayed with their mothers until 35 days of age. After weaning, the does were sacrificed. Tissue samples of liver and perirenal fat were collected for chemical analyses. Additionally, based on samples taken from one female, RNA expression levels were determined from the mammary gland and liver, adipose tissue and skin. It was found that homozygous does with deletion at codon 248 of the BCO2 gene were characterized by considerably higher concentrations of xanthophylls and beta‐carotene in the liver, adipose tissue and milk than does with the remaining genotypes. However, the differences in the content of the above compounds in milk had no influence on litter weight or the number and rearing rate of kittens. Additionally, RNA expression of the BCO2 gene was found in the mammary tissue of lactating doe and its level was similar to those noted in the liver and adipose tissue.  相似文献   
64.
本试验旨在研究蛋氨酸羟基类似物异丙酯(HMBi)对福建黄兔屠宰性能、肠道组织形态和肠道酶活的影响。选取体重相近、健康的断奶福建黄兔100只(公、母各半),随机分为4组,每组5个重复,每个重复5只。对照组饲喂基础日粮,Ⅰ、Ⅱ、Ⅲ组在基础日粮中分别添加0.20%、0.40%、0.60% HMBi。预试期10 d,正试期52 d。结果表明,①与对照组相比,Ⅱ组屠体重和屠宰率分别显著和极显著提高(P<0.05;P<0.01),Ⅱ、Ⅲ组胴体重显著提高(P<0.05)。②与对照组相比,Ⅱ组十二指肠和空肠绒毛高度极显著提高(P<0.01),Ⅲ组空肠和回肠绒毛高度极显著提高(P<0.01);Ⅰ、Ⅱ、Ⅲ组十二指肠和空肠隐窝深度显著或极显著降低(P<0.05;P<0.01),Ⅱ、Ⅲ组回肠隐窝深度显著提高(P<0.05);Ⅰ、Ⅱ、Ⅲ组十二指肠和回肠绒毛高度/隐窝深度比值显著或极显著提高(P<0.05;P<0.01),Ⅲ组空肠绒毛高度/隐窝深度比值极显著提高(P<0.01)。③与对照组相比,Ⅱ、Ⅲ组淀粉酶活性显著提高(P<0.05)。综上所述,HMBi可提高福建黄兔的屠宰率,改善小肠黏膜形态,增加肠道酶活性;在本试验条件下,福建黄兔日粮中HMBi的适宜添加水平为0.40%。  相似文献   
65.
Rabbit sera (n = 1600) from 40 commercial farms were submitted to a serological screening for Encephalitozoon cuniculi by an enzyme-linked immunosorbent assay (ELISA) and a carbon immunoassay (CIA test). Antibodies anti-Encephalitozoon cuniculi were found in 505/1600 (31.6%) sera analysed, and all the farms (100%) resulted positive. Rabbits older than 4 months showed a significantly higher seropositivity for E. cuniculi (chi-squared test: p < 0.0001) than rabbits under 4 months, E. cuniculi sero-prevalence showed an increasing trend in rabbits within the farm along with the increase in the “number of rabbits on the farm”; however, this trend was not significant (Spearman’s correlation: p = 0.073).The findings of the present study confirm that rabbit is the main reservoir of E. cuniculi; they are of epidemiological relevance and immediate public health importance because of the recognized infectivity in humans by the microsporidium.  相似文献   
66.
观察母兔妊娠20、26、29天和15、30、60、90日龄八点黑獭兔的子宫组织,以探讨八点黑獭兔子宫的形态学发育特点。结果表明:獭兔的子宫随着年龄的增长.其内膜的粘膜上皮由假复层柱状纤毛上皮逐渐分化成紧密规则的单层柱状上皮;固有层在15~30日龄之间出现.内含大量间质细胞;妊娠期固有层发生水肿和充血;子宫肌层在幼龄时分层不明显,各层肌纤维互相交织,随平滑肌细胞分裂增生,3月龄时肌层出现明显的内环、外纵两层,中间形成一层环状排列的血管:獭兔出生后其子宫内膜腺由子宫内膜上皮细胞内陷形成,随后腺上皮细胞经有丝分裂增生,15日龄幼兔已形成单管子宫腺。该研究结果可为兔的解剖学、生殖生理学增添新的内容,也为进一步研究兔生殖系统疾病的治疗与预防提供参考资料。  相似文献   
67.
选择年龄、体重基本一致,生长发育正常的健康獭兔种母兔24只,随机分成对照组以及A、B、c3个试验组,每组6只,对照组饲喂养殖场现有日粮(蛋白水平为15%),试验组分别饲喂蛋白质水平为16%、18%、20%的日粮,研究不同蛋白质水平对獭兔繁殖性能的影响。结果表明。不同营养水平对窝产仔数、初生窝重没有明显影响,各组差异不显著(P〉0.05),但对泌乳力、断奶窝重、断奶个体重等有明显影响。B组的泌乳力、断奶窝重与对照组相比差异显著(P〈0.05),分别比对照组提高47.6%和1573.42g;断奶个体重,A组和B组均显著高于对照组(P〈0.05),比对照组分别高30.9%和47.4%,B组显著高于A组(P〈0.05),比A组高12.6%,C组与对照组差异不显著(P〉0.05);各组断奶成活数、成活率差异不显著(P〉0.05)。  相似文献   
68.
对通辽市某獭兔种免场采集到的病死兔组织进行细菌分离,通过形态鉴定、生化鉴定、药敏试验、动物致病性试验等一系列诊断,证实链球菌感染是引起兔死亡的主要原因。根据药敏试验结果,对免群进行针对性治疗.使病情得到有效控制。  相似文献   
69.
分别对30~40日龄、60~90日龄、120~150日龄、180日龄以上4个阶段八点黑獭兔消化管的长度进行测定并对其有关结构进行观察描述。结果显示:40~90日龄期间消化管处在不断的生长发育中,并研究发现结肠狭窄部(长度4-5cm),回盲口与盲结口分开,直肠长度5-6cm,胃容积的大小与供料多少有密切关系。研究结果为我国家兔解剖学补充了新的内容。  相似文献   
70.
采国敬  何玉琴  许然 《安徽农业科学》2009,37(26):12549-12550
[目的]分析氟中毒对獭兔机体生理功能的影响,为獭兔氟中毒提供血液生理诊断依据。[方法]以9只体重2.O-2.5kg的健康成年獭兔为试验对象,采用氟化钠溶液灌胃建立獭兔氟中毒模型,对试验兔采血测定血液生理指标,比较獭兔氟中毒前后血液相关生理指标、体重、精神状态等变化,分析氟对獭兔机体血液生理功能的影响。[结果]獭兔氟中毒后,獭兔红、白细胞、血小板、中性白细胞、淋巴细胞、单核细胞数与对照组相比明显降低(P〈0.01);嗜酸性、嗜碱性白细胞数明显增多(P〈0.01);血红蛋白含量、红细胞比容明显降低。血细胞沉降率明显升高(P〈0.05);大部分红细胞膜形态出现不规则的星芒状突起。[结论]氟中毒对獭兔血液生理功能有明显的影响。  相似文献   
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