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61.
A. O. Lala O. L. Ajayi N. Okwelum A. O. Oso T. V. Fakorede T. A. Adebayo J. E. Jagbojo 《Tropical animal health and production》2018,50(5):1005-1010
The aim of this study was to evaluate the effects of dietary supplementation of Morinda lucida leaf meal (MLLM) on the haematology, biochemical and organ changes of broiler chickens. One hundred and ninety-eight day-old Marshall broiler chicks were completely randomised into 6 treatments in a 3?×?2 factorial arrangement of three levels of M. lucida leaf meal supplementation (0, 0.1 and 0.2 g/kg) with or without medication. The treatment consisted of both negative (without MLLM and routine medication) and positive (containing no MLLM but with routine medication) control groups while each treatment was replicated thrice. MLLM-supplemented diets and routine medication decreased (p?<?0.05) the white blood cell count compared to the negative control. Dietary supplementation with MLLM in combination with normal routine medication increased (p?<?0.05) total serum protein when compared with treatment group without MLLM and routine medication. Dietary supplementation with MLLM and routine medication reduced (p?<?0.05) serum creatinine concentration of the broiler chickens. Birds fed with 0.2 g/kg MLLM supplement coupled with medication and those on negative control had higher (p?<?0.05) creatinine values. Serum enzyme activities reduced (p?<?0.05) following supplementation. MLLM supplementation recorded no significant effect (p?>?0.05) on the liver, kidney, heart and gizzard. M. lucida leaf meal can be compared to routine medication for improved health status of broiler chickens. Dietary inclusion with 0.1 g/kg MLML combined with routine medication could be used in producing healthy and safe chickens. 相似文献
62.
Zimbabwe’s smallholder dairying faces many challenges that affect the welfare of dairy cows; however, the status of this welfare has not yet been determined. A cross-sectional study was conducted in Midlands Province on 41 active smallholder dairy farms with 86 cows in winter and summer to determine the risk factors and indicators to impaired cow welfare. These objectives were achieved using farmer questionnaires and direct observations. Eleven percent of the observed cows were severely lame in summer while only 5% were severely lame in winter. Lameness was significantly associated with season, absence of shade, breed, and low dipping frequency; 58% of the cows had low body condition scores (BC?<?3) and this low BC was associated with low frequency of protein (p?=?0.002) and vitamin (p?=?0.012) supplementation recorded in more than 52% of the farms visited. In winter, only 11% of the observed cows were heavily soiled (score 3), while in summer 64% of the cows were heavily soiled and this was associated with slurry accumulation in more than 80% of the observed cattle pens as well as the study season (p?<?0.001). A quarter (26%) of the studied animals had visible teat lesions on the teat skin and this was associated with the type of lubricant used (p?=?0.011). Only 34% of the cows allowed an approaching stockman to touch them and this was associated with shouting (p?=?0.012) and whipping of cows (p?=?0.002). The study concluded that welfare of dairy cows was poor in most of the smallholder dairy farms studied. 相似文献
63.
Branched‐chain amino acid ratios in low‐protein diets regulate the free amino acid profile and the expression of hepatic fatty acid metabolism‐related genes in growing pigs 下载免费PDF全文
Y. H. Duan F. N. Li C. Y. Wen W. L. Wang Q. P. Guo Y. H. Li Y. L. Yin 《Journal of animal physiology and animal nutrition》2018,102(1):e43-e51
Liver metabolism is affected by nutrients. The aim of this study was to explore the effects of low‐protein diets (17% crude protein, CP) supplemented with branched‐chain amino acids (BCAAs), including leucine (Leu), isoleucine (Ile) and valine (Val), on hepatic amino acid profile and lipid metabolism in growing pigs. The ratio of Leu : Ile : Val in all groups was 1 : 0.51 : 0.63 (20% crude protein, CP), 1 : 1 : 1 (17% CP), 1 : 0.75 : 0.75 (17% CP), 1 : 0.51 : 0.63 (17% CP) and 1 : 0.25 : 0.25 (17% CP) respectively. Results revealed that compared to the positive control group (1 : 0.51 : 0.63, 20% CP), the low‐protein diets significantly augmented the concentrations of most essential amino acids and non‐essential amino acids (p < .05), with the greatest values observed in the 1 : 0.25 : 0.25 group. Moreover, relative to the control, the low‐protein diets with the Leu : Ile : Val ratio ranging from 1 : 0.75 : 0.75 to 1 : 0.25 : 0.25 markedly downregulated the mRNA abundance of acetyl‐CoA carboxylase (ACC), lipoprotein lipase (LPL) and fatty acid‐binding protein 4 (FABP‐4) (p < .05), and upregulated the mRNA expression of hormone‐sensitive lipase (HSL), peroxisome proliferator‐activated receptor‐g coactivator‐1α (PGC‐1α), uncoupling protein 3 (UCP3) and liver carnitine palmitoyltransferase 1 (L‐CPT‐1) (p < .05). Therefore, our data suggest that protein‐restricted diets supplemented with optimal BCAA ratio, that is, 1 : 0.75 : 0.75–1 : 0.25 : 0.25, induce a shift from fatty acid synthesis to fatty acid oxidation in the liver of growing pigs. These effects may be associated with increased mitochondrial biogenesis. 相似文献
64.
为建立一种羊种布鲁氏菌Rev.1疫苗株PCR-RFLP鉴定方法,利用羊种布鲁氏菌Rev.1具有链霉素抗性的特性,选取与链霉素抗性相关编码核糖体蛋白S12的rps L基因为模板设计引物,经PCR扩增后,将产物进行Nci I酶切,发现羊种布鲁氏菌疫苗株Rev.1出现约500 bp条带,而不具有链霉素抗性的羊种布鲁氏菌株16M则出现384 bp条带。结果表明,PCR-RFLP方法能够用于羊种布鲁氏菌Rev.1疫苗株的鉴定,这为今后区分羊种布鲁氏菌疫苗株Rev.1免疫与野株感染提供了基础。 相似文献
65.
66.
作物秸秆综合利用三原则——就地、大量、简易还田 总被引:7,自引:0,他引:7
中国年产作物秸秆7.0×108 t,是一笔宝贵的自然资源.但由于利用主体方向不明确,配套措施不力,致使大量秸秆被随地焚烧,严重污染环境,影响了农业的可持续发展.本文从分析秸秆焚烧现象的严重性入手,综述了秸秆利用的现状,提出了秸秆资源利用的三项原则,并推出了一项省工节本高效的秸秆利用新技术. 相似文献
67.
Jianjiang Li Ningning Han Hao Zhang Xiaoyu Xie Yaoyao Zhu E Zhang Jiahui Ma Chuangeng Shang Mengxiong Yin Weidong Xie Xia Li 《Marine drugs》2022,20(9)
Moromycin B (Mor B), saquayamycin B1 (Saq B1), saquayamycin B (Saq B), and landomycin N (Lan N), four angucyclines produced by the marine-derived actinomycete Streptomyces sp., are a class of polyketone compounds containing benzanthracene. Here, the structure–activity relationship of these four compounds was analyzed in human colorectal cancer (CRC) cells. Saq B1, which showed the strongest cytotoxicity with an IC50 of 0.18–0.84 µM for CRC cells in MTT assays, was employed to test underlying mechanisms of action in SW480 and SW620 cells (two invasive CRC cell lines). Our results showed that Saq B1 inhibited CRC cell proliferation in a dose- and time-dependent manner. Notably, lower cytotoxicity was measured in normal human hepatocyte cells (QSG-7701). Furthermore, we observed proapoptosis, antimigration, and anti-invasion activities of Saq B1 in CRC cells. At the same time, the protein and mRNA expression of important markers related to the epithelial–mesenchymal transition (EMT) and apoptosis changed, including N-cadherin, E-cadherin, and Bcl-2, in Saq B1-treated CRC cells. Surprisingly, the PI3K/AKT signaling pathway was shown to be involved in Saq B1-induced apoptosis, and in inhibiting invasion and migration. Computer docking models also suggested that Saq B1 might bind to PI3Kα. Collectively, these results indicate that Saq B1 effectively inhibited growth and decreased the motor ability of CRC cells by regulating the PI3K/AKT signaling pathway, which provides more possibilities for the development of drugs in the treatment of CRC. 相似文献
68.
多元文化背景下大学生人生价值取向调查与分析 总被引:1,自引:0,他引:1
通过自编问卷以特定选择方式对318名大学生进行人生价值取向调查,结果表明,当前大学生价值取向受多元文化影响明显,具有较强的利己倾向,重现实层面、轻理想层面和责任意识相对较弱等特点.对此需要正确应对多元文化的侵袭,加强传统文化的宣扬与传播,构建和谐大学文化,并加强学生自我教育来保障学生人生价值选择的理性倾向. 相似文献
69.
薰衣草油与肉桂油对朱砂叶螨的生物活性和行为分析 总被引:1,自引:0,他引:1
为明确在室内条件下薰衣草油、肉桂油对朱砂叶螨Tetranychus cinnabarinus(Boisduval)的生物活性,采用喷雾、熏蒸法测定了薰衣草油和肉桂油对朱砂叶螨的触杀活性、产卵抑制活性和熏蒸活性,并分析了2种精油的亚致死剂量对雌成螨运动行为的影响。结果表明:与肉桂油相比,薰衣草油对朱砂叶螨的触杀活性较强,经浓度为1%的薰衣草油喷雾处理后,雌成螨、若螨24 h后的死亡率分别为64.07%和52.22%,LC_(50)分别为0.41%和0.89%;浓度为2%的薰衣草油对雌成螨产卵的抑制作用最强;与肉桂油相比,薰衣草油的熏蒸活性也较强,熏蒸雌成螨6、12和24 h后的死亡率分别为70.37%、85.19%和95.19%,LD_(50)分别为0.94、0.59和0.39μL;随精油剂量增加雌成螨运动轨迹紊乱,触壁反射活动减少,移动范围明显减小,而移动频率先升高后降低。研究表明,与肉桂油相比,在朱砂叶螨的生物防治中薰衣草油具有更高的应用价值。 相似文献
70.
本文通过室内贴牌水培法及整株法,快速鉴定并验证了2013年采自湖南省不同地区稻田的50个稗草生物型对二氯喹啉酸的抗药性,试验结果表明:贴牌水培法所用的二氯喹啉酸甄别剂量为80mg/L;稗草死亡率越低,其抗性倍数(resistance factor,RF)越高,其中死亡率为0时,整株法测定的RF值高达896.07~1 209.38;贴牌水培法测定的稗草样本对二氯喹啉酸的ED50远低于整株法,但两种方法得到的不同稗草生物型对二氯喹啉酸的抗性水平趋势高度吻合。笔者认为以贴牌水培法测定的死亡率小于40%的稗草样本对二氯喹啉酸的抗性风险较高,值得深入研究。 相似文献