Effect of nutrition and endoparasitic treatment on growth, onset of puberty and reproductive activity in Menz ewe lambs

Ewe lambs of the Ethiopian Menz breed were assigned at weaning (90+/-3 days) to four levels of nutrition (poor, low, medium and high) to achieve different premating growth rates with or without treatment for endoparasites. A concentrate mixture providing 2.5 Mcal/kg dry matter (DM) metabolizable energy and 15.2 g/kg DM digestible protein was used. Improved nutrition increased lamb postweaning average daily weight gain up to puberty by 6 to 26 g/day and the conception rate to first estrus by 9 to 16% while it reduced the mortality rate by 24 to 31% and age at first lambing by 2 to 5 months. Lambs reached puberty (age at first estrus) at 16.9+/-0.1 kg (+/-SEM) or 60% of mature body weight and 350+/-12 days of age. The onset of puberty was advanced by weaning weight (P<0.05), itself being well correlated with birth weight (r = 0.51, P<0.001), and by level of nutrition (high=299+/-19, medium=301+/-18, low=383+/-23 and poor=454+/-31 days, P<0.001) through enhanced growth rate (r = -0.82, P<0.001). No independent effect of drenching for endoparasites on pubertal development was observed (P>0.05), but its interaction with season-of-birth improved the growth of lambs born during the period of short rains (P<0.05). Overall mean litter size at first lambing was 1.07; the twinning rate was 6.5% and the birth weight was 1.9+/-0.1 kg. Up to 13.4% of newborn lambs, averaging 1.3+/-0.6 kg, died on the day of parturition. The results indicate that improved growth rate and body weight, resulting from better postweaning nutrition, affects the attainment of puberty in Menz ewe lambs. Mitigation of nutrition stress and endoparasitic infection depending on season-of-birth would thus increase the annual reproductive rate of breeding ewes and flock productivity.     

Morphological variation of Echinococcus granulosus protoscoleces from hydatid cysts of human and various domestic animals in Jordan

, and 1988. Morphological variation of Echinococcus granulosus protoscoleces from hydatid cysts of human and various domestic animals in Jordan. International Journal for Parasitology 18: 1111–1114. Rostellar hook morphology of protoscoleces was employed to study the possible existence of Echinococcus granulosus strains in humans and various domestic animals in Jordan. A distinct form in the donkey was evident as the protoscoleces from this host did not share any characteristics with those from the other hosts examined. Sheep, goats and cattle appeared to be affected by another form since the protoscoleces from their hydatid cysts shared six out of nine characteristics studied. Protoscoleces of camel and human cysts shared seven out of nine characteristics studied and they were different in six characteristics from protoscoleces from other hosts. Differences observed among the three forms may reflect strain variation of E. granulosus in this country.     

Further studies on prevalence of hydatidosis in slaughtered animals from North Jordan

Examination of 471 sheep, 118 goats, 157 cattle and 56 camels slaughtered in abattoirs in North Jordan was carried out during March-May 1984. Drought conditions that prevailed during the preceding winter led to slaughtering old female sheep (greater than or equal to 4 years) due to scarcity of food, which allowed us to analyse the prevalence of hydatidosis in various age groups of sheep. An overall infection rate of 27.8, 1.7, 5.8 and 10.7 percent was found in sheep, goats, cattle and camels, respectively. The infection rate was as low as 1.5 percent in male and 1.9 percent in female sheep under 2 years of age. However, the rate of hydatid infection increased with age and reached as high as 63.7 percent in ewes 4 years of age and older. The percentage of animals with fertile cysts was also highest in sheep (68.7 percent of infected animals) and increased with age reaching 100 percent in ewes which were 10 years of age or older. Analysis of all cysts recovered from the livers and lungs of infected ewes from various age groups revealed a sharp increase in the mean total number of cysts in age groups over 8 years of age. The fertility rate of the cysts in the liver was significantly greater in ewes 6 years old or more (64.8--78.6 percent) than in younger age groups (8.7-46.2 percent). In the lung, the fertility rate increased progressively with age reaching as high as 97.9 percent in ewes 10 years old or more. These findings of high infection and fertility rates of hydatid disease in sheep, particularly of older age groups, prompt plans for further epidemiological studies and control programmes.     

Biological and physicochemical characterization of recombinant human erythropoietins fractionated by Mono Q column chromatography and their modification with sialytransferase

Ten erythropoietin (EPO) fractions differing in sialic acid content, ranging from 9.5 to 13.8 mol mol^–1 of EPO, were obtained from baby hamster kidney cell-derived recombinant human EPO by Mono Q column chromatography. The mean pI values of the EPO fractions determined by IEF-gel electrophoresis systematically shifted from 4.11 to 3.31, coinciding with the sialic acid content, without a change in the constitution of asialo N-linked oligosaccharides of each fraction. Although a linear relationship between thein vivo bioactivity and the sialic acid content of the fractionated, samples was observed until 12.1 mol mol^–1 of EPO, there was no further increase in their activity over 12.4 mol mol^–1 of EPO. On the other hand, an inverse relationship between thein vitro bioactivity and sialic acid content of EPO was observed. Also, we showed that thein vivo bioactivity of some fractions with low sialic acid contents was increased after treatment with 2,6-sialyltransferase, but thein vivo bioactivity of the other fractions with high sialic acid contents was either decreased or not affected.Abbreviations EPO erythropoietin - rHuEPO recombinant human erythropoietin - hCG human chorionic gonadotropin - BHK baby hamster kidney - CHO Chinese hamster ovary - NeuAc N-acetyl neuraminic acid - Gal galactose - HRCs hemolyser-resistant cells - WST-1 2-(4-iodophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium Na - IEF isoelectric focusing - pI isoelectric point     

The Pectinase produced by Tubercularia vulgaris in submerged culture using pectin or orange-pulp pellets as inducer

The growth of four strains of the shiitake mushroom Lentinus edodes in solid substrate fermentation in synthetic oak sawdust logs was studied over a 14-week period. Total extracellular phenol oxidase activity and soluble protein were monitored and biomass estimated as the ergosterol content of the fermented sawdust. It was observed that two of the strains had a similar pattern of phenol oxidase activity with two cycles with maxima at 2 and 8 weeks of mycelial growth prior to fruiting. With the other two strains there was a maximum at week 4. For each strain, phenol oxidase activity increased with the cold shock used to induce fruiting. Phenol oxidase activity was not found to be correlated with either soluble protein or total fungal biomass in the fermented sawdust, which were correlated for each strain. Quantification of biomass from submerged liquid culture on the basis of dry weight and ergosterol contents showed that the strains fell into the same two groups with respect to the ergosterol to biomass ratio, which was markedly lower than that for a strain of L. lepideus.Correspondence to: B. C. Okeke     

Uptake of biotin by human hepatoma cell line,Hep G2: A carrier-mediated process similar to that of normal liver

Little is known about the cellular and molecular regulation of the uptake process of the water-soluble vitamin biotin into liver cells, the major site of biotin utilization and metabolism. Such studies are best done using a highly viable and homogeneous cellular system that allows examination of prolonged exposure to an agent(s) or a particular condition(s) on the uptake process. Isolated hepatocytes when maintained in primary culture lose their ability to transport biotin by the specialized carrier system. The aim of the present study was, therefore, to examine the mechanism(s) of biotin uptake by the cultured human-derived liver cells, Hep G₂. Uptake to biotin by Hep G₂ cells was appreciable and linear for up to 10 min of incubation. The uptake process was Na⁺ gradient-dependent as indicated by studies of Na⁺ replacement and pretreatment of cells with gramicidin and ouabain. Biotin uptake was also dependent on both incubation temperature and intracellular energy. Unlabeled biotin and the structural analogs with free carboxyl groups (thioctic acid, desthiobiotin) but not those with blocked carboxyl group (biocytin, biotin methyl ester, and thioctic amide) caused significant inhibition of ³H-biotin uptake at 37°C but not 4°C. Initial rate of biotin uptake was saturable as a function of concentration at 37°C but was lower and linear at 4°C. Pretreatment of Hep G₂ cells with sulfhydryl group inhibitors (e.g., p-chloromer-curibenzene sulfonate) led to a significant inhibition in biotin uptake; this inhibition was effectively reversed by reducing agents (e.g., dithiothreitol). Biotin uptake was also inhibited by the membrane transport inhibitors probenecid (noncompetitively), DIDS and furosemide but not by amiloride. Pretreatment of Hep G₂ cells with valinomycin did not alter biotin uptake. The stoichiometric ratio of biotin to Na⁺ uptake in Hep G₂ cells was also determined and found to be 1:1. These findings demonstrate that biotin uptake by these cultured liver cells is mediated through a specialized carrier system that is dependent on Na⁺-gradient, temperature, and energy and transports the vitamin by an electroneutral process. These findings are similar to those seen with native liver tissue preparations and demonstrate the suitability of Hep G₂ cells for in-depth investigations of the cellular and molecular regulation of biotin uptake by the liver. © 1994 Wiley-Liss, Inc.

1 This article is a US Government work, and as such, is in the public domain in the United State of America

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Chemical synthesis of insulin-like peptide 1 and its potential role in vitellogenesis of the kuruma prawn Marsupenaeus japonicus

The insulin superfamily comprises a group of peptides with diverse physiological functions and is conserved across the animal kingdom. Insulin-like peptides (ILPs) of crustaceans are classified into four major types: insulin, relaxin, gonadulin, and androgenic gland hormone (AGH)/insulin-like androgenic gland factor (IAG). Of these, the physiological functions of AGH/IAG have been clarified to be the regulation of male sex differentiation, but those of the other types have not been uncovered. In this study, we chemically synthesized Maj-ILP1, an ILP identified in the ovary of the kuruma prawn Marsupenaeus japonicus, using a combination of solid-phase peptide synthesis and regioselective disulfide bond formation reactions. As the circular dichroism spectral pattern of synthetic Maj-ILP1 is typical of other ILPs reported thus far, the synthetic peptide likely possessed the proper conformation. Functional analysis using ex vivo tissue incubation revealed that Maj-ILP1 significantly increased the expression of the yolk protein genes Maj-Vg1 and Maj-Vg2 in the hepatopancreas and Maj-Vg1 in the ovary of adolescent prawns. This is the first report on the synthesis of a crustacean ILP other than IAGs and also shows the positive relationship between the reproductive process and female-dominant ILP.     

Exploring the Therapeutic Properties of Alga-Based Silver Nanoparticles: Anticancer,Antibacterial, and Free Radical Scavenging Capabilities

The current study was designed to evaluate the antioxidant, anticancer and antimicrobial activities of silver nanoparticles (AgNPs) biosynthesized by Spirulina platensis extract. The biosynthesized silver nanoparticles were characterized using Fourier transform infrared (FT-IR) analysis, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD) analysis. The antioxidant activity of the biosynthesized AgNPs were determined via DPPH radical scavenging assay while its anticancer activity was determined using the MTT assay. The antimicrobial activity of the biosynthesized AgNPs were analyzed by disc diffusion method. Spirulina platensis acts as a reducing and capping agent. The efficacy of silver nanoparticles (AgNPs) in inhibiting the growth of Gram-negative bacteria, specifically Acetobacter, Klebsiella, Proteus vulgaris, and Pseudomonas aeruginosa, was assessed by the utilisation of the diffusion method. The study aimed to evaluate the efficacy of biosynthesized silver nanoparticles (AgNPs) against many strains of Pseudomonas aeruginosa bacteria. The findings of the study revealed that when administered in doses of 50 μl, 75 μl, and 100 μl, the largest observed zone of inhibition corresponded to measurements of 10.5 mm, 14 mm, and 16 mm, respectively. A zone of inhibition with dimensions of 8 mm, 10.5 mm, and 12 mm was detected during testing against Acetobacter at concentrations of 50 μl, 75 μl, and 100 μl, respectively. The findings also indicate that there is a positive correlation between the concentration of AgNP and the DPPH scavenging ability of silver nanoparticles. The percentage of inhibition observed at concentrations of 500 μg/ml, 400 μg/ml, 300 μg/ml, 200 μg/ml, and 100 μg/ml were recorded as 80±1.98, 61±1.98, 52±1.5, 42±1.99, and 36±1.97, respectively. In addition, it was observed that the silver nanoparticles exhibited the greatest antioxidant activity at a concentration of 500 g/ml, with a measured value of 80.89±1.99. The IC-50 values, representing the inhibitory concentration required to achieve 50 % inhibition, were found to be 8.16, 19.15, 30.14, 41.13, and 63.11 at inhibition levels of 36±1.97, 42±1.99, 52±1.5, 61±1.98, and 80±1.98, respectively.