Lack of glucokinase regulatory protein expression may contribute to low glucokinase activity in feline liver

In most mammals, glucokinase (GK) acts as a hepatic “glucose sensor” that permits hepatic metabolism to respond appropriately to changes in plasma glucose concentrations. GK activity is potently regulated by the glucokinase regulatory protein (GKRP), which is encoded by the GCKR gene. GKRP binds GK in the nucleus and inhibits its activity. GK becomes active when it is released from GKRP and translocates to the cytosol. Low glucokinase (GK) activity is reported to be a principal feature of feline hepatic carbohydrate metabolism but the molecular pathways that regulate GK activity are not known. This study examined the hypothesis that species-specific differences in GKRP expression parallel the low GK activity observed in feline liver. Hepatic GKRP expression was examined using RT-PCR, immunoblot, and confocal immunomicroscopy. The results show that the GCKR gene is present in the feline genome but GCKR mRNA and the GKRP protein were absent in feline liver. The lack of GKRP expression in feline liver indicates that the low GK activity cannot be the result of GKRP-mediated inhibition of the GK enzyme. However, the absence of the permissive effects of GCKR expression on GK expression and activity may contribute to reduced GK enzyme activity in feline liver. The study results show that the cat is a natural model for GCKR knockout and may be useful to study regulation of GCKR expression and its role in hepatic glucose-sensing and carbohydrate metabolism.     

Genetic correlations among reproductive traits and uterine dimensions in mice

The objective of this experiment was to identify relationships among reproductive and uterine traits in mice having normal or crowded uterine conditions. Littermate females were randomly assigned to be either unilaterally ovariectomized (ULO) or to remain intact (C) and to be killed either 3 d after mating (PM) or 4 d after parturition (PP) in a 2 x 2 factorial design. Measurements taken were ovulation rate (OR) and uterine length (UL), wet weight (UWW), dry weight (UDW) and displacement (UDP) in PM females and number born (NB) and implantation rate (IMP) in PP females. Heritability estimates from full-sib correlations were .18, .01, .33, .04, .14, .47 and .06 for OR, IMP, NB, UL, UWW, UDW and UDP, respectively. Phenotypic correlations among uterine measurements were moderate to high and positive. Genetic correlations for C and ULO females for OR with NB were .62 and .73, respectively. Genetic correlations between C and ULO females were .53 for NB and 1.05 for OR. Genetic correlations of UL and UWW with NB were high for C (.70 and .59, respectively) and moderate for ULO (.47 and .36, respectively). Genetic correlations between NB and other uterine dimensions were lower.     

芒属(Miscanthus)植物种质资源研究进展

芒属植物属禾本科多年生高大草类,多分布于热带非洲至亚洲东南部。近年来在欧美国家受到广泛的关注,被认为是一种开发潜力巨大的生物质能源。本文查阅近年国内外相关文献,对芒属植物的生境、分布、遗传多样性、光合特性、抗性生理生化、繁殖学、饲草利用以及作为能源植物的研究等方面做了综述,并展望了其研究前景,旨在推动芒属种质资源的研究。     

日粮添加免疫生长促进剂C96对雏鸡若干血液指标的影响

选择１２０只１日龄ＡＡ商品健康雏鸡,随机分为４组,每组３０只。初步观察了日粮添加免疫生长促进剂Ｃ９６对血液中红细胞总数（ＲＢＣ）、比容（ＰＣＶ）、血红蛋白含量（Ｈｂ）、网织红细胞比例（ＲＣＣ）、白细胞总数（ＷＢＣ）等的影响。结果表明：肉雏鸡在１５ｄ时,日粮添加Ｃ９６为１１ｍｇ／ｋｇ,饲料的Ｃ９６组和疫苗－Ｃ９６组,与对照组和疫苗组比较,ＲＢＣ和Ｈｂ增高,ＷＢＣ显著下降,ＲＣＣ降低,ＰＣＶ无明显规律性变化;３０ｄ和４５ｄ时,添加Ｃ９６组和疫苗－Ｃ９６组的ＲＢＣ、Ｈｂ和ＰＣＶ,与对照组和疫苗组基本相近,ＷＢＣ和ＲＣＣ均比对照组和疫苗组低或明显低。但３０ｄ时疫苗组的ＷＢＣ比对照组高。整个试验期,ＲＢＣ、ＷＢＣ和ＰＣＶ随日龄的增长呈上升趋势,ＲＣＣ呈波动性下降。     

Prevalence of antimicrobial residues in raw table eggs from farms and retail outlets in Enugu State,Nigeria

The use of antimicrobial agents in poultry production results in their accumulation in the body tissues and products such as milk and egg. The subsequent accumulation of these drugs and their metabolites in body cells is known as drug residue. This study was designed to determine the prevalence of antimicrobial residues in eggs from poultry farms and retail outlets in Enugu State, Nigeria. Eggs from 25 selected commercial farms and ten retail outlets were screened for the prevalence of antimicrobial residue. Also, structured questionnaires were administered to 25 commercial farms in the state to determine the management practices and the most widely used antimicrobial drugs in farms and possible association between the management practices and the occurrence of antimicrobial residues in eggs from these farms. All the 25 farms surveyed use oxytetracycline. Eggs from nine of the surveyed farms tested positive for antimicrobial residue and three of the ten surveyed farms also tested positive for antimicrobial residue. No association was observed (p 0.05; Fisher’s exact test) between the occurrence of antibiotic residues in eggs and farm size, feed source and housing systems. This study was able to demonstrate the presence of antimicrobial residues in eggs destined for human consumption. Drugs like nitrofurans which has been banned for use in food animals are still very much in use in Enugu State, Nigeria. Antibiotics given as feed additives may give rise to drug residues in food animals.     

<Emphasis Type="Italic">Echinococcus granulosus</Emphasis>: Immunoprotection accompanyied by humoral and cytokine response against secondary hydatidosis in mice immunized with r<Emphasis Type="Italic">Eg.</Emphasis>myophilin

Objects:  

This study aimed to investigate the immunoprotection of the recombinant Eg.myophilin (rEg.myophilin) and tentatively analyze mechanism of this protection.