Three SNPs within exons of INHA and ACVR2B genes are significantly associated with litter size in Dazu black goats

The aim of this study was to analyse the association between single-nucleotide polymorphisms within INHA and ACVR2B and litter size in Dazu black goats. In total, twenty-two SNPs were genotyped in 190 individuals by SNaPshot and resequencing. The results showed that three SNPs (SNP_1, SNP_12 and SNP_13 in this study) were detected to have significant additive genetic effect on the recorded goat litter size (p < .05). The SNP_1 (NC_030809.1), a non-synonymous substitution of G for T at chr2-g. 28314990 in the exon 2 of INHA gene (NM_001285606.1), resulted in homozygote 2 (HOM2) contributed 0.25 and heterozygote (HET) contributed 0.12 larger litter than homozygote 1 (HOM1). Meanwhile, SNP_12 (Chr22-g. 11721225 A > T) and SNP_13 (Chr22-g. 11721227 A > C) (NC_030829.1) simultaneously mutated at the first and third position of a triplet AAA (lysine, K) in the exon 4 of ACVR2B gene (XM_018066623.1) had estimated genetic effects of HOM1 (0.00) and HOM2 (0.03) larger than HET (−0.12). In conclusion, one SNPs (chr2-g. 28314990 T > G) within the exon 2 of INHA and two SNPs (Chr22-g. 11721225 A > T and Chr22-g. 11721227 A > C) i n the exon 4 of ACVR2B gene were highly recommended as candidate markers of litter size in Dazu black goats. A large-scale association study to assess the impact of these variants on litter size is still necessary.     

Kernel vitreousness and protein content: Relationship,interaction and synergistic effects on durum wheat quality

Four sets of durum samples were used in this study to further understand the interrelationships among hard vitreous kernels (HVK), protein content, and pigment concentration, with a focus on the interaction and synergistic effects of protein content and vitreousness on durum quality. HVK level increases with higher protein content in the range of 9.5–12.5%, but this relationship is less evident in durum samples with high protein content (12.5–14.5%). Both protein content and kernel vitreousness can significantly affect durum milling quality. White starchy kernels (WSK) in low protein durum have a very detrimental impact on milling and pasta processing quality, but high protein content can mitigate the adverse impact of WSK on durum quality. Although protein content plays a dominant role, higher HVK might contribute positively to pasta firmness. There was no significant difference in yellow pigment content between HVK and WSK. However, pigment loss from semolina to dough was higher for WSK than HVK. Despite the difference in protein content, HVK and WSK have little difference in gluten strength. The monomeric protein was preferentially accumulated in HVK. The glutenin proteins of HVK and WSK were similar in the ratios of 1Bx/1By and HMW/LMW-GS.     

应用多重PCR检测人工感染鸡呼吸道疾病的研究

本文报道了IBV，NDV，ILTV，MG人工感染4周龄SPF鸡和非免疫鸡后，用多重PCR检测试验鸡的咽喉棉拭子和器官组织样品，并与传统的病原分离鉴定，血清学方法进行比较，多重PCR无论是对单一感染病原，还是对两种以上混合感染病原，其敏感性和检测速度都优于传统的鉴别诊断方法，具有较高的实用价值，可以直接应用于临床检测，服务于生产。     

分散松香施胶剂性能影响因素的探讨

对逆转法制备分散松香施胶剂过程中的主要因素如乳化剂的种类及用量、马来松香加合物含量、搅拌转速、加料速度和乳化温度等系统地进行了探讨，提出了合理的工艺条件，并对实际生产中可能出现的问题及解决办法进行了阐述。     

波尔山羊杂交后代体尺、体重与肉用性能的相关性研究

本文利用 SPSS数据处理软件 (10 .0版 )统计分析了 2 3只 (约 8～ 9月龄 )波尔山羊与唐山奶山羊杂交后代公羊的体尺、体重和肉用性能。结果表明 :(1)波尔山羊与唐山奶山羊杂交 F1 代体尺、体重与肉用性能指标的变异程度大于 F2 代 ,其中宰前重、胴体重、净肉重和胸宽四项指标变异程度在 F1 和 F2 代中都很大 ;(2 )杂交 F1 代、F2 代各项指标 t检验结果 ,除胸宽外其余指标差异显著或极显著 ;(3 )波尔山羊杂交后代中胸宽与各项指标间相关不显著 ,宰前重、胴体重、净肉重与体尺指标相关显著或不显著。     

猪血浆转铁蛋白与部分经济性状关系的研究——Ⅰ. 多态性与产仔数和日增重的关系

用经改进的聚丙烯酰胺凝胶电泳铁染法,测定了二花脸猪血浆转铁蛋白多态类型,分析了其基因型频率和基因频率,并探讨了猪血浆转铁蛋白多态性与产仔性能和增重速度的相关性。     

Reproductive roles predict sexual dimorphism in internal and external morphology of lake whitefish,Coregonus clupeaformis

Abstract – The different reproductive roles of the sexes can predict the direction and magnitude of sexual dimorphism of external and internal morphology. Males should have enlarged structures that enhance the acquisition of mating opportunities, whereas females are predicted to have enlarged organs that are associated with the production of eggs. We tested these predictions in male and female lake whitefish, a species in which both sexes have similar overall body size and shape. After controlling for body size, male lake whitefish had significantly longer jaws and pectoral and pelvic fins, larger hearts, and more muscle than females. Sexual dimorphism in relative muscle mass may be one of the most fundamental morphological differences between males and females. Females had relatively heavier livers than males. Because the liver is important for the breakdown of fats and vitellogenesis, selection should favour an enlarged liver in females for the processing of energy and the production of large numbers of eggs.     

湖北省土壤各级颗粒的磁化率

本试验对湖北省六种土壤五个粒级(>1,1-0.5,0.5-0.25,0.25-0.15.0.15-0.1mm)的磁化率进行了测定。结果表明:红壤、棕红壤、潮土和黄棕壤表土层磁化率大于母质层磁化率,而紫色土和黄褐土表土层磁化率小于下部土层的磁化率。棕红壤表土层磁化率小于淀积层磁化率。红壤、棕红壤、黄棕壤和黄褐土母质层磁化率随颗粒变细而明显增加,但这一现象在潮土、紫色土的母质层确不明显。0.25-0.15mm粒级是黄棕壤、红壤、棕红壤、潮土、紫色土磁化率随颗料大小变化的一个转折点。     

农业土地规模经营的理论探讨

实现农业土地规模经营,有利于生产力有效运转并取得最佳的规模效益。其适度性受各种因素的影响,具有区域性和动态性。规模经营与劳动生产率有着密切的关系,应该在确保提高土地生产率的基础上来提高劳动生产和土地规模经营的效益。土地适当集中、土地经营主体的总人数尽量精简和劳动组合的优化是优化土地经营规模的三个相互制约的因素。要采取积极的措施逐步实现土地的规模经营。对现有土地经营形式要做具体分析,其调整应从有利于生产力发展出发,在尊重群众意愿的基础上稳步进行。