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61.
本试验旨在研究饲粮中添加高水平的钙和维生素D3对AA肉仔鸡肉品质和血液生化指标的影响。试验采用2×2完全随机因子设计,选用240只21日龄AA肉仔鸡,随机分成4个处理,每个处理6个重复,每个重复10只。试验期为28 d。玉米-豆粕型基础日粮中含钙0.90%、维生素D3 750 IU/kg,日粮中共设两个钙水平(0.9%,1.15%)和两个维生素D3水平(750、5000 IU/kg)。结果表明:(1)在AA肉仔鸡饲粮中单独添加1.15%的钙对肌肉嫩度影响显著(P<0.05),5000 IU/kg维生素D3对肌肉嫩度影响不显著(P>0.05),同时添加钙和维生素D3的互作效应对肌肉嫩度影响显著(P<0.05);(2)1.15%的钙显著降低胆固醇、甘油三酯、低密度脂蛋白的含量(P<0.05),显著升高了高密度脂蛋白的含量(P<0.05);(3)单独添加5000 IU/kg维生素D3显著降低了低密度脂蛋白的含量(P<0.05)。以上研究结果表明,玉米-豆粕型基础日粮中长期添加1.15%钙和5000IU/kg维生素D3能够减小肌肉剪切力,降低血液中总胆固醇和甘油三酯的含量,从而提高肉品质。 相似文献
62.
饲粮中添加不同生物制剂对杜寒杂交肉羊生产性能和屠宰性能的影响 总被引:1,自引:0,他引:1
本试验旨在比较饲粮添加不同生物制剂对杜寒杂交肉羊生产性能、屠宰性能、组织器官发育及肉品质的影响。采用单因素试验设计,选取平均体重约为32 kg的杜寒杂交F1代肉羊160只,随机分为5组,每组4个重复,每个重复8只。对照组采用基础饲粮,试验组分别添加21 mg/kg莫能菌素、4×109CFU/kg地衣芽孢杆菌、3.2×109CFU/kg酿酒酵母菌、1.1 g/kg复合生物制剂(地衣芽孢杆菌≥6×109CFU/g、酿酒酵母菌≥4×109CFU/g、碱性蛋白酶≥1 000 U/g)。预试期10 d,正试期56 d,每2 d记录1次采食量,每20 d进行1次称重,当复合生物制剂组羊只的平均体重达到约50 kg时,每组选取10只羊进行屠宰,测定其屠宰性能、组织器官重量和肉品质指标。结果表明:1)复合生物制剂组平均日增重、屠宰率显著高于对照组(P0.05);地衣芽孢杆菌组和复合生物制剂组料重比显著低于对照组(P0.05)。2)地衣芽孢杆菌组、酿酒酵母菌组、复合生物制剂组复胃重量均显著高于对照组(P0.05),复合生物制剂组复胃重量占宰前活重比例显著高于对照组和莫能菌素组(P0.05);地衣芽孢杆菌组、酿酒酵母菌组、复合生物制剂组小肠重量及其占宰前活重比例均显著高于对照组、莫能菌素组(P0.05)。3)酿酒酵母菌组肾脏重量占宰前活重比例显著高于对照组(P0.05),其他内脏器官重量占宰前活重比例在各组间无显著差异(P0.05)。4)各组肉品质指标差异不显著(P0.05)。综合得出,从作为饲料添加剂对肉羊生产性能作用效果来看,地衣芽孢杆菌、酿酒酵母菌、复合生物制剂可以替代莫能菌素,地衣芽孢杆菌好于酿酒酵母菌,复合生物制剂最佳。 相似文献
63.
目的:探讨口服"开口健"对小鼠淋巴细胞功能以及营养生长因子的影响。方法:36只ICR小鼠随机分为4组,即生理盐水组",开口健"低、中、高剂量组。给小鼠连续灌胃10 d后,用MTT法检测淋巴细胞刺激指数,RT-PCR方法检测ConA刺激后淋巴细胞产生的IL-4、IL-10、IL-12和INF-γmRNA水平,ELISA方法检测小鼠血清胰岛素样生长因子(IGF-1)和生长激素释放肽(Ghrelin)水平。结果:口服"开口健"小鼠脾脏淋巴细胞SI显著高于对照组(P〈0.01),并随"开口健"剂量的增加而升高;口服"开口健"小鼠脾脏淋巴细胞产生IL-4、IL-10、IL-12和IFN-γmRNA水平显著高于对照组(P〈0.05)。口服"开口健"显著提高了小鼠血清的IGF-1和Ghrelin水平(P〈0.05),且与"开口健"剂量呈正相关性。结论:口服"开口健"可增强小鼠淋巴细胞功能并提高血清营养生长因子水平。 相似文献
64.
Lingyan Zhang Xing Tao Zhang Pingting Jin Hongbo Zhao Xue Liu Qingkai Sheng 《Animal Science Journal》2021,92(1):e13593
To evaluate the effects of Spirulina platensis and probiotics on growth, immunity indexes, fecal flora, and fecal odor in mice, 40 mice were randomly allotted to four groups, and each was administrated with nothing, S. platensis, probiotics, or both for 28 days, respectively. Then, many indexes were measured. The results showed that S. platensis was more effective (P < 0.001) than probiotics in improving mice's feed conversion ration (FCR). In immunity, probiotics administration increased (P < 0.042) serum IgE, IgM, IFN-γ, colonic AHR, TLR4, and NF-κB protein expression and decreased (P < 0.039) serum IL-1α, IL-21, IL-22, and colonic ARNT gene expression. However, the S. platensis showed weaker effect, which increased (P < 0.025) the serum IgE, IgM, TNF-α, and the colonic AHR and NF-κB protein expression, and decreased (P < 0.01) serum IL-21. Probiotics consumption decreased the fecal odor by decreasing (P < 0.02) fecal Escherichia coli, indole-3-acetic acid (IAA), and skatole contents, and the S. platensis decreased (P = 0.04) the IAA. These results indicated that oral administration of probiotics, S. platensis, or both of them in mice probably benefited body's immunity and reduced fecal odor. However, their mechanisms were still unclear and need further study. 相似文献
65.
Angela Gimmel Sabine Öfner Annette Liesegang 《Journal of animal physiology and animal nutrition》2021,105(Z2):24-28
In the veterinary profession, the body condition score (BCS) plays an important role in the assessment of patients. It is a subjective, tactile method of evaluating body fat and muscle mass and is used in numerous species. Recognizing obesity (or the contrary, emaciation) is important for veterinarians treating reptiles and could be facilitated by a BCS. An existing form of body condition assessment already used is the body condition index (BCI), where the residuals from a regression of body mass on body length are calculated. Therefore, the goal of this study was to provide practitioners with a BCS system for corn snakes (Pantherophis guttatus) and to test it against the BCI. A total of 22 corn snakes (Pantherophis guttatus), stationed at the “Auffangstation für Reptilien” in Munich (reptile rescue centre, RRC), were subject of this study. Each had the following measurements taken: body weight (BW), snout–tail tip length (STL), snout–vent length (SVL) and circumference in the middle (C). Manual palpation of spine, area between vertebral spinous and transverse process, ribs and neck of each snake was performed by three veterinarians and assigned to specific scores by each examiner. A BCS (mean of examiners’ scores) was given to each snake according to manual palpation. The BCS system was chosen to be out of 5 in 0.5-point steps with 2.5 considered as ideal BCS. In the studied snakes, the BCS ranged from 1.5 to 3.5, with a median of 2.5. The median BW was 309 g (75–967 g), the median STL was 123 cm (79–153 cm), the median SVL was 104 cm (73–133 cm) and the median C was 7.5 cm (4.3–11 cm). BCS and BCI were positively correlated. A BCS includes a manual palpation of the animal and thus gives the examiner additional information to the objectively measured/calculated index. 相似文献
66.
67.
本研究旨在探讨猪源唾液乳杆菌对生长猪氮表观消化率和血清指标的影响。选用平均体重为(35.22±0.86)kg长×大二元杂交猪81头,随机分成3组,每组3个重复,每个重复9头。对照组饲喂基础日粮,试验组分别在基础日粮中添加0.20%、0.40%猪源唾液乳杆菌冻干制剂,试验期为30 d。结果表明:添加0.20%、0.40%的猪源唾液乳杆菌冻干制剂可显著提高生长猪氮表观消化率(P<0.05);与对照组相比,2个试验组猪血清白球比显著降低(P<0.05),尿素氮、乳酸脱氢酶、肌酸激酶含量分别比对照组降低了14.77%和13.42%(P<0.05)、16.92%和20.0%(P<0.05)、28.96%和23.00%(P<0.01),但2个试验组间差异不显著(P>0.05)。结果提示,日粮中添加猪源唾液乳杆菌能够提高生长猪氮表观消化率,改善血清指标,减少应激,且以添加剂量为0.20%时效果最好。 相似文献
68.
为研究复方中草药添加剂对稻鸭共作模式下成都麻鸭生长性能、血清生化指标、抗氧化指标及免疫指标的影响,试验选取体重相近、体况健康的15日龄成都麻鸭240只,随机分为4组,每组5个重复,每个重复12只。4组为对照组饲喂基础饲粮;试验1、2、3组在基础饲粮中按照质量比分别添加0.5%(低剂量组)、1%(中剂量组)、2%(高剂量组)的复方中草药,试验期90 d。结果显示:(1)试验1、2、3组的平均日增重分别较对照组提高2.19%、4.34%、4.98%(P<0.05);试验2、3组的料重比分别较对照组降低3.37%、3.63%(P<0.05);(2)试验2组和3组的总蛋白(TP)分别较对照组提高4.20%、6.08%(P<0.05);试验2组和3组的尿素氮(BUN)分别较对照组降低12.72%、16.36%(P<0.05);试验2组和3组的谷草转氨酶(ALT)分别较对照组降低15.84%、19.22%(P<0.05);试验3组的谷丙转氨酶(AST)较对照组降低19.34%(P<0.05);(3)试验2组和3组超氧化物歧化酶(SOD)分别较对照组提高15.80%、20.00%(P<0.05);试验3组的总抗氧化能力(T-AOC)较对照组提高22.37%(P<0.05);(4)三个试验组的IgA、IgM、IgG、IFN-γ、IL-2显著高于对照组(P<0.05),试验2组的肿瘤坏死因子-α(TNF-α)较对照组提高10.06%(P<0.05),试验2组和3的组溶菌酶(LZM)分别较对照组提高6.79%、5.66%(P<0.05)。综上,中草药添加剂能有效提高稻鸭共作模式下成都麻鸭的生长性能、血清生化指标、抗氧化指标及免疫指标,本试验条件下,最佳饲喂剂量为1%。 相似文献
69.
西北旱区喷灌条件下紫花苜蓿生长特征与品质指标的关系 总被引:1,自引:0,他引:1
西北旱区由于独特的气候条件,生产的苜蓿干草品质好,产量高。如何根据苜蓿的田间指标估测干草品质参数,对于苜蓿草产品生产销售具有重要意义。研究在喷灌条件下不同灌溉量对紫花苜蓿的生长品质的影响,并利用生长指标对紫花苜蓿的品质进行预测。试验于2014至2015年于中国农业大学石羊河流域生态节水试验站进行为期2年的田间试验。试验共设3个灌溉处理:A1灌溉量为100%紫花苜蓿蒸腾蒸散量(ETc),A2,A3的灌溉量分别为A1处理的66%,33%,以及一个不灌溉处理A4。结果表明,苜蓿生长指标如株高(H)和茎叶比(SLR)随生育期的推进呈上升趋势,而鲜干比(FDR)呈下降趋势;所有生长指标随着灌溉量的减少均呈下降趋势。在品质方面,随着生育期的推进,所有处理的粗蛋白(CP)呈下降趋势,而中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)则呈现上升趋势;随着灌溉量的降低,NDF与ADF呈下降趋势,而CP则呈上升趋势。各生长指标与品质指标的拟合结果表明,H和SLR均与各品质指标显著线性相关(P<0.001),且H与品质拟合结果相关系数最高(R2>0.900),而FDR则与各品质指标不显著。这些结果表明,在田间管理较好,长势良好,杂草与病虫害发生较少的情况下,可以用株高对苜蓿干草品质做出预测。 相似文献
70.
The objective of the study has been to verify the hypothesis that the coat colour is regarded in the selection of Polish Thoroughbred horse population. Formally, the colour is not a selection criterion in this breed selected mainly for speed. The material consisted of twelve groups of foals registered in successive volumes of the Stud Book (11,688 foals, in total) and their parents selected to the breeding stud. The frequency of alleles in ASIP, MC1R and GREY loci controlling the coat colours was estimated from the recessive phenotype frequency square in the groups of foals. The inflow of foreign genes was limited and the population great, hence the migration effect was very low. The drift and Wahlund effect hardly influenced the genetic structure in the groups which enabled to analyze the population not divided. The total offspring frequency of recessive a, e and g alleles amounted to 0.1552, 0.4877 and 0.9773, respectively. Accuracy of the assessment of the a and e frequency was confirmed on the basis of test matings. The a, e and g alleles were more frequent in dams than in sires and the a alleles occurred more often in fillies than in colts. The frequency of a and e alleles was higher in the offspring than in the parents. The genotype distribution in the offspring differed from the expected one, assessed from the gamete frequency in sires and in dams. Fewer bay foals were born than anticipated. All the results show that the coat colour is not entirely disregarded in the breeding of Thoroughbred horses. The dominant A and E alleles producing the colour are preferred in the selection, particularly in the sires. This leads to some alterations in the phenotypic structure of the population. On the other hand, the horses are mated randomly, irrespective of the coat colour. 相似文献