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991.
Mohammad Ali Behroozlak Mohsen Daneshyar Parviz Farhoomand Abbas Nikoo 《Animal Science Journal》2021,92(1):e13645
A total of 250 one-day-old Ross 308 male chicks were used to investigate the effects of Fe-methionine (Fe-met) and iron sulfate (FeSO4.7H2O) on performance, mineral concentration, meat quality, and oxidative stability of breast. The feeding experiment was performed with five dietary groups including group I (basal diet [BD] + 80 mg/kg FeSO4), group II (BD + 60 mg/kg FeSO4 + 20 mg/kg Fe-met), group III (BD + 40 mg/kg FeSO4 + 40 mg/kg Fe-met), group IV (BD + 20 mg/kg FeSO4 + 60 mg/kg Fe-met), and group V (BD + 80 mg/kg Fe-met). The results showed that Fe and Cu content in the breast muscle increased by dietary supplementation of organic and inorganic iron from II to V groups. Dietary groups of II, IV, and V increased L* value and b* value of breast meat. Additionally, redness of breast meat enhanced linearly and quadratically by dietary supplementation of 80 mg/kg Fe as FeSO4. In addition, dietary supplementation Fe from II to V groups led to a significant increase in pHu at 24-h postmortem while it was negatively correlated with L* value of breast muscle. This study demonstrates that replacing FeSO4 with Fe-Met could improve breast meat yield of broilers. Although 80 mg of Fe-Met improved the iron content of meat, it showed detrimental effects on the lipid oxidation of breast meat. 相似文献
992.
Niyazi Küçük Uğur Uçan Sanan Raza Güneş Erdoğan Melih Aksoy 《Reproduction in domestic animals》2021,56(8):1059-1065
Laparoscopic artificial insemination technique (LAI) is described to overcome reduced fertility problems in sheep artificial insemination (AI) programmes with frozen semen. Later on, this technology was modified for endangered non-domestic cats to deposit low quality or reduced number of sperm cells hardly obtained by electro-ejaculation into the oviduct. This technique by passes the complex structure of cervix and efficiently transfers the sperm cells to the point of fertilization. In recent years, rabbits are becoming popular transgenic animal models producing various therapeutic and commercial products, as well as being experimental animals for disease models. The worldwide transportation of frozen semen and re-establishment of transgenic lines using AI technology has become a common practice. Therefore, this study was designed to describe a laparoscopic intrauterine insemination technique, which might assist in conceiving the animals with limited number of sperm cells. The female rabbits were laparoscopically (n = 22) or vaginally (n = 13) inseminated with frozen–thawed semen samples containing approximately 10 × 106 motile sperm. The laparoscopic insemination technique provided higher pregnancy rate (45.5%) than vaginal insemination technique (7.7%) (p < .05). In conclusion, the described laparoscopic AI might be a new alternative technique, thus enabling limited or low-quality frozen sperm samples to establish pregnancy in rabbits. 相似文献
993.
为探究鸡日粮中添加包被肉桂油对肉鸡生长性能、屠宰性能、肌肉品质和肌肉风味的影响,试验选用168只1日龄罗斯308雏鸡,随机分成2个处理组,对照组饲喂基础日粮,试验组在基础日粮中添加300 mg/kg的包被肉桂油。结果显示:与对照组相比,试验组肉鸡活体重没有显著的差异(P>0.05);21日龄胸肌的a^*值和b^*值(P<0.05)和42日龄胸肌和腿肌的24 h pH值(P<0.05)提高,21和42日龄胸肌和腿肌的滴水损失(P<0.05)降低;21日龄胸肌中过氧化氢的含量和42日龄胸肌丙二醛含量(P<0.01)降低;腿肌中的甜味氨基酸(丝氨酸和甘氨酸)(P<0.05)和芳香族氨基酸(酪氨酸和苯丙氨酸)的含量(P<0.01)提高。研究表明:日粮中添加300 mg/kg的包被肉桂油能够改善肉鸡肌肉品质的部分指标,提高胸肌抗氧化力和腿肌风味。 相似文献
994.
为了研究不同精粗比全混合日粮对山羊肉品质、血清指标和器官发育的影响,将体重相近、健康的4月龄努比亚黑山羊36只随机分为3组,每组12只羊。试验组山羊分别饲喂低精粗比(40∶60,L)、中精粗比(50∶50,M)和高精粗比(60∶40,H)全混合日粮,试验为期70 d。结果表明:1)不同精粗比日粮对整个试验期山羊的体尺指标无显著影响(P>0.05)。2)正试期第14天,H组山羊血清谷草转氨酶(aspartate aminotransferase,AST)、谷丙转氨酶(alanine aminotransferase,ALT)和肌酸激酶(creatine kinase,CK)活性显著低于L组(P<0.05);正试期第56天,H组山羊血清AST/ALT值显著高于L组(P<0.05),但碱性磷酸酶(alkaline phosphatase,ALP)活性则相反。3)H组山羊肌肉失水率显著低于其他两组(P<0.05),但肌肉pH则相反;M组肌肉红度显著低于其他两组(P<0.05),各组间其他项目无显著性差异(P>0.05)。4)L组山羊的瘤胃重量、肝脏重量和肝脏指数显著高于H组(P<0.05),而肺指数则相反;M组山羊网胃重量、网胃指数、瓣胃重量、瓣胃指数和皱胃指数著高于L组(P<0.05),而脾脏重量和脾脏指数则相反。5)L组山羊十二指肠绒毛高度、VH/CD和空肠VH/CD显著高于H组(P<0.05),而空肠的隐窝深度则相反;M组山羊回肠绒毛高度和VH/CD显著高于H组(P<0.05)。综上所述,低精粗比日粮能够促进努比亚山羊胃肠道发育,高精粗比日粮能够提高山羊肉品质。从本试验结果来看,采用低精粗比(40∶60)日粮对努比亚山羊进行育肥较好。 相似文献
995.
对青海省柴达木地区青海高原毛肉兼用半细毛羊9个主要经济性状进行了遗传力估测。结果表明,初生重、断奶重、周岁剪毛量、羊毛细度、毛长、剪毛前体重、剪毛量都是高遗传力性状,也是青海高原毛肉兼用半细毛羊育种过程中的主要选择依据;断奶重、周岁剪毛量、剪毛前体重与剪毛量之间呈强正遗传相关,断奶重可作为对剪毛量进行早期选择的参数;断奶重与羊毛细度之间呈负遗传相关。 相似文献
996.
Transnasal administration of a combination of dexmedetomidine,midazolam and butorphanol produces deep sedation in New Zealand White rabbits 下载免费PDF全文
997.
This trial was conducted to study the effect of Monascus compound additives on growth performance and meat quality of broilers.The total of 400 one-day-old Avian broilers were randomly allotted into 4 groups with 5 replicates per group and 20 birds per replicate.The broilers in group Ⅰ(control group),were fed a basal diet,and those in experimental groups Ⅱ,Ⅲ and Ⅳ were fed the basal diet supplemented with 0.5%,1% and 1.5% Monascus compound additives,respectively.The experiment lasted for 42 d.At the ending of the experiment,all the birds were weighted and two of each replicate were slaughtered,the samples from breast and leg muscles were taken for meat quality measurement.The results showed as follows:Compared with control group,the ADG increased significantly(P<0.05),and F/D decreased significantly(P<0.05)in group Ⅲ and Ⅳ,but the differences were not significant between group Ⅲ and Ⅳ(P>0.05);Compared with the control group,the muscle redness(a*)and yellowness(b*)in all the experimental groups increased significantly(P<0.05),and the drip loss rate decreased significantly(P<0.05),but the muscle lightness(L*),cooking loss rate and shear force had no significant change(P>0.05),and pH24 h of muscles in groups Ⅲ and Ⅳ reduced significantly(P<0.05).In conclusion,adding Monascus compound additives in diets could improve growth performance and meat quality in broiles, and the appropriate level should be 1%. 相似文献
998.
Anne‐Marika Siponen Paula M. Kinnunen Joanna Koort Hannimari Kallio‐Kokko Olli Vapalahti Anna‐Maija Virtala Pikka Jokelainen 《Zoonoses and public health》2019,66(2):207-215
Practising veterinary medicine has an inherent risk of exposure to zoonotic agents, including the protozoan parasite Toxoplasma gondii. We screened sera of veterinarians authorized to work in Finland for the presence of specific immunoglobulin G antibodies against T. gondii with an enzyme‐linked fluorescent assay, and evaluated potential risk factors for T. gondii seropositivity from extensive questionnaire data with almost 1,300 quantitative variables. We used a causal diagram approach to address the complexity of the life cycle of the parasite and its numerous possible transmission routes, and built a multivariable binomial logistic regression model to identify risk factors that are particularly relevant for veterinarians. The samples and questionnaire data were collected in 2009. Altogether, 294 veterinarians, almost 15% of the Finnish veterinary profession, were included in the study. The median age was 39 years, and the majority, 86%, were women. Altogether, 43 (14.6%; 95% confidence interval: 10.9–19.0) of the 294 veterinarians tested seropositive for T. gondii. According to the final model, veterinarians who were at least 40 years old had 2.4 times higher odds to be seropositive than younger veterinarians; veterinarians who lived in the countryside had 4.0 times higher odds to be seropositive than veterinarians who lived in towns; female veterinarians who tasted beef during cooking had 2.6 times higher odds to be seropositive than male veterinarians who did not taste beef during cooking; and veterinarians who did not do small animal practice had 2.3 times higher odds to be seropositive than those who did. The results illustrate the numerous transmission routes of T. gondii. 相似文献
999.
1000.