Effects of Wnt10b on dermal papilla cells via the canonical Wnt/β‐catenin signalling pathway in the Angora rabbit

Wnt10b is a member of Wnt family that plays a variety of roles in biological functions, including those in the development of hair follicles. To investigate the effect of Wnt10b on hair growth in the Angora rabbit and to determine the underlying molecular mechanism, we cultured dermal papilla (DP) cells with exogenous Wnt10b in vitro. We observed the expressions of downstream critical gene β‐catenin and lymphoid enhancer‐binding factor 1 (LEF1) in Wnt/β‐catenin pathway. The levels of β‐catenin mRNA and protein were higher in the Wnt10b group of DP cells than in the Control group, and the mRNA level of LEF1 in the Wnt10b group was higher than in the Control group. Moreover, translocation of β‐catenin from cytoplasm to nucleus was activated in the Wnt10b group. Furthermore, the mRNA levels of the hair follicle‐regulatory genes, insulin‐like growth factor‐1 (IGF‐1) and alkaline phosphatase (ALP), and the protein activity of ALP was also upregulated in the Wnt10b group compared to their corresponding levels in the Control group. These data suggest that Wnt10b could activate the canonical Wnt/β‐catenin signalling pathway to induce DP cells in the Angora rabbit. In addition, the proliferation of DP cells was significantly promoted when cultured with Wnt10b for 48 and 72 hr, suggesting that Wnt10b plays a pivotal role in the proliferation and maintenance of DP cells in vitro. In conclusion, this study demonstrates that Wnt10b may promote hair follicle growth in Angora rabbit through the canonical Wnt/β‐catenin signalling pathway that promotes the proliferation of DP cells.     

Pharmacokinetics of sanguinarine,chelerythrine, and their metabolites in broiler chickens following oral and intravenous administration

Sanguinarine (SA) and chelerythrine (CHE) are the main active components of the phytogenic livestock feed additive, Sangrovit®. However, little information is available on the pharmacokinetics of Sangrovit® in poultry. The goal of this work was to study the pharmacokinetics of SA, CHE, and their metabolites, dihydrosanguinarine (DHSA) and dihydrochelerythrine (DHCHE), in 10 healthy female broiler chickens following oral (p.o.) administration of Sangrovit® and intravenous (i.v.) administration of a mixture of SA and CHE. The plasma samples were processed using two different simple protein precipitation methods because the parent drugs and metabolites are stable under different pH conditions. The absorption and metabolism of SA following p.o. administration were fast, with half‐life (t_1/2) values of 1.05 ± 0.18 hr and 0.83 ± 0.10 hr for SA and DHSA, respectively. The maximum concentration (C_max) of DHSA (2.49 ± 1.4 μg/L) was higher that of SA (1.89 ± 0.8 μg/L). The area under the concentration vs. time curve (AUC) values for SA and DHSA were 9.92 ± 5.4 and 6.08 ± 3.49 ng/ml hr, respectively. Following i.v. administration, the clearance (CL) of SA was 6.79 ± 0.63 (L·h^?1·kg^?1) with a t_1/2 of 0.34 ± 0.13 hr. The AUC values for DHSA and DHCHE were 7.48 ± 1.05 and 0.52 ± 0.09 (ng/ml hr), respectively. These data suggested that Sangrovit® had low absorption and bioavailability in broiler chickens. The work reported here provides useful information on the pharmacokinetic behavior of Sangrovit® after p.o. and i.v. administration in broiler chickens, which is important for the evaluation of its use in poultry.     

蓝海战略与饲料营销(1)

<正>第一章饲料蓝海1正大饲料20世纪70年代前,中国几乎没有工业饲料及饲料工业的概念。畜禽养殖还处于一家几头猪、几只鸡的农户散养的初始阶段,没有养殖成本、利润意识,养猪为过年,养鸡为换盐,只为     

重庆市水产品质量安全现状及对策

我国是世界上最大的渔业生产国,其养殖产量占全世界养殖产量的2/3。我国也是水产品出口大国,2006年水产品出口量为301.5万吨,出口额93.6亿美元,占农产品出口总额的     

南瓜冰淇淋的制作技术

利用新鲜南瓜为原料,经处理后加入到冰淇淋配料中。结果表明,当南瓜、奶粉、人造奶油、鸡蛋、白砂糖、乳化稳定剂、香兰素添加量分别为10%、10%、4%、5%、13%、0.8%、0.1%时,所得到的冰淇淋风味独特,营养价值高,膨胀率和感官指标较好。     

湛江地区小尾寒羊生产性能分析与评价

通过对引入湛江地区小尾寒羊生长性能、繁殖性能的测定、统计以及与原产地进行对比、分析与评价,研究了小尾寒羊在湛江地区的适应性。试验分别测定小尾寒羊初生、2～3月龄、6～7月龄、周岁和成年的平均体重;2～3月龄、6～7月龄、周岁的平均日增重及小尾寒羊的产仔记录,并与原产地进行比较。结果表明,引入湛江地区的小尾寒羊在生产性能的各项指标上都体现出对当地环境具有一定的适应能力,但是同原产地相比,还存在着一定的差距。因此,在经过遗传选育、风土驯化的同时,还应加强饲养管理水平,以提高小尾寒羊在湛江地区的适应性及生产性能。     

陕西省鸡肾型传染性支气管炎病毒的分离鉴定

从临床表现呼吸道传染病的20个发病鸡群中先后分离出18株病毒,通过鸡胚感染、血清学试验、分子生物学试验、动物回归试验证明其中13株是冠状病毒科的鸡传染性支气管炎病毒,3株为新城疫病毒,2株为H9禽流感病毒。该13株中的BJ2、FF2、YL2、B01、G5、YX、WH、WG分离毒具有很强的嗜肾性和致病力,这8个陕西流行株的血清型与W118毒株相同,而与IBVGray株、W93株有一定的差异。结果表明,陕西地区主要流行鸡肾型传染性支气管炎,且流行株具有强致病力。     

The efficacy of some drugs with known antiprotozoal activity against Histomonas meleagridis in chickens

Nine drugs with known or suspected antiprotozoal activity were tested in vitro, and in vivo for activity against Histomonas meleagridis. The nitroimidazoles dimetridazole, metronidazole, ornidazole, and tinidazole suppressed growth of H. meleagridis in vitro at 10 microg/ml or higher. Paromomycin sulfate, and carbadox were weakly effective at high levels. Quinolinol, mebendazole, diloxanide furoate, and albendazole had no demonstrable efficacy in vitro. Drugs showing some activity in vitro were tested in young chickens inoculated intracloacally with 2 x 10(5) H. meleagridis/bird. Dimetridazole, metronidazole, ornidazole, and tinidazole were highly effective at 200 ppm in feed. Paromomycin sulfate, and carbadox were ineffective in vivo, with no improvement in liver or cecal lesion scores compared to that of infected controls. Thus, the only new entities with efficacy against blackhead disease in vivo were nitroimidazoles, related to the positive control dimetridazole.     

7种能量饲料淀粉降解率的研究

以6头装有永久性瘤胃瘘管的浏阳去势黑山羊为实验动物,利用瘤胃尼龙袋技术研究大麦、大米、高粱、荞麦、小麦、小米、玉米等7种常用谷物饲料淀粉在羊瘤胃内的降解率规律。结果表明各种饲料淀粉有效降解率(%)顺序为:大麦>小麦>玉米>大米>荞麦>高粱>小米。其中以大麦的淀粉有效降解率最高达97.05%,小米的最小为36.43%,其它依次为96.28%、55.37%、45.23%、44.10%、42.58%。     

低压射流不同喷嘴参数及压力下破碎过程实验

研究了不同低压下喷头喷嘴直径和喷嘴锥角对射流破碎的影响。采用高速摄像仪对低压圆柱射流的射流核心长度和射流破碎长度进行实验,测量了不同喷嘴结构的流量、射程和末端水滴直径。结果表明:同一压力下,当喷嘴锥角不变时,随着喷嘴直径的增大,喷头流量、射程和喷头末端水滴直径都变大,射流核心长度和破碎长度均增大;当喷嘴直径不变时,随着喷嘴锥角的增大,喷头流量逐渐减小,而喷头射程呈先增大后减小趋势,喷头末端水滴直径也变大,射流核心长度逐渐减小,射流破碎长度先减小后增大。综合考虑射程和雾化效果,直径为5 mm、锥角为45°的喷嘴为最优选择。同时通过对不同Re数和We数的实验和分析,给出了适合低压喷嘴的两种射流特征长度的拟合关联式。