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There are three main breeds of goat in Nigeria: The West African Dwarf (WAD), the Red Sokoto and the Sahel. Goats are renowned for their hardiness and can survive in most environments. The goats sampling was carried out from farms and markets across different states in Nigeria, according to the geographical distribution of the breeds published by Blench (1999). This experiment was carried out to analyse morphological variability among Nigerian goats. A total of 318 goats spread across the three Nigerian breeds were used in the following populations (57 Sahel, 187 Red Sokoto and 137 West African Dwarf). Data were collected on body weight, linear body measurements and heat tolerance traits and were subjected to analysis of variance using the fixed effects of breed, sex and location. Results showed that breed, sex and location significantly (P

The present study was conducted to determine the effects of adding fruit-juices to semen extenders on viability of buck spermatozoa during cryopreservation in two studies. Pooled semen samples obtained from West African Dwarf (WAD) goat bucks were diluted with Tris-egg yolk based extenders. In study I, the diluted semen samples were supplemented with orange ( Citrus sinensis ), cucumber ( Cucumis sativus ) and pineapple ( Ananas comosus ) juices (2.5, 5, 7.5 and 10 ml/100 ml). In study II, the diluted semen samples were supplemented with 5 ml/100 ml of different combinations of fruit-juices consisting of pineapple and orange juices (TEYPO) at a 1:1 ratio, pineapple and cucumber juices (TEYPC) at a 1:1 ratio, orange and cucumber juices (TEYOC) at a 1:1 ratio, and pineapple, orange and cucumber juices (TEYPOC) at a 1:1:1 ratio, respectively. The diluted semen samples were cryopreserved and thereafter evaluated for sperm viability parameters. The extenders supplemented with 7.5 and 10% orange, and 10% pineapple had higher (P < 0.05) motility compared to the control. There was higher (P < 0.05) acrosome integrity in extenders supplemented with orange and pineapple at all levels compared to the control while cucumber at 10% had higher (P < 0.05) acrosome integrity compared to other levels and the control. The extenders supplemented with cucumber, orange and pineapple had higher (P < 0.05) membrane integrity compared to the control except at 7.5% of extender supplemented with cucumber. Similarly, the extenders supplemented with cucumber, orange and pineapple had lower (P < 0.05) sperm abnormality compared to the control. The extenders supplemented with cucumber, orange and pineapple at 2.5, 10 and 7.5% respectively had lower (P < 0.05) concentrations of MDA compared to other levels and the control. There was higher motility and acrosome integrity in extenders supplemented with different combinations of fruit-juices (P < 0.05) compared to the control. TEYPC had higher (P < 0.05) membrane integrity and lower (P < 0.05) concentrations of MDA compared to the control. The findings revealed that extenders supplemented with orange and pineapple at 10% consistently improved motility, acrosome integrity and membrane integrity, and reduced sperm abnormality compared to the control while no particular combination of these fruit-juices was consistently superior in all the parameters.

Aim: To study the emergence of the community-acquire CTX-M beta-lactamase genes among the residents in Abeokuta, Nigeria. Study Design: To determine the prevalence rate of CTX-M beta-lactamase genes in enteric multiresistant ESBL isolates found among the Abeokuta residents. Place of Study: Abeokuta, Nigeria between August 2010 and March 2013. Methodology: Beta-lactamase and ESBL producing enteric bacteria were identified and their antimicrobial susceptibility was tested against commonly used antibiotics. Mating activity of the Original Research Article Akinduti et al.; BMRJ, 5(4): 351-358, 2015; Article no.BMRJ.2015.036 352 isolates was evaluated and their plasmid was profiled while a CTX-M chromosomal gene was assayed by PCR. Results: Of the 27.4% beta-lactamase producers obtained, only 5.1% of the strains were ESBL and 2.8% harboured blaCTX-M genes. High resistance rate of 91.0% by Escherichia coli and Klebsiella oxytoca to commonly used antibiotics was observed. Conclusion: There is urgent need to curb the community spread of undetected mobile genetic elements of CTX-M-encoded enteric bacteria among the residents in this community and if this persists, a possible outbreak of enteric infection caused by resistant organisms is eminent.

There has been a growing interest on the effects of access to pasture on poultry health status. However, there is a paucity of data on the relative benefits of grass and legume pastures. An experiment was conducted to determine the effects of rearing systems {deep litter system (DL), deep litter with access to legumes (LP) or grass (GP) pastures} haematology and serum chemistry of ISA Brown layers. The study involved the use of two hundred and forty 12 weeks old pullets. The birds were reared until 60 weeks of age. Eighty birds were assigned to each treatment; each treatment had four replicates of 20 birds each. Blood samples (2.5 ml) were collected from the wing vein of two birds per replicate and serum chemistry and haematological parameters were determined. The results showed that there were no significant differences between treatments in all the parameters considered at 18 weeks of age. At 24 weeks old, the percentage of heterophyl (HET) in DL and LP were similar but higher than that of GP. The ratio of H:L was higher (P

Se estudiaron los efectos sinérgicos del factor de crecimiento II similar a la insulina (ICF-II) solo o asociado a hormona folículo estimulante (FSH), sobre la producción de progesterona y estradiol por las células de granulosa bovinas (GC) cultivadas in vitro. Las GC, obtenidas de ovarios de vacas sacrificadas, fueron cultivadas durante cuatro días en incubador óxido de carbono (IV) a 37°C y 5% de CO2 en aire atmosférico y 100% de humedad relativa, usando el medio de cultivo de tejidos 199 (TCM 199). El medio, fue cambiado al segundo día y se añadió testosterona como sustrato para la producción de estradiol. El IGF-II solo o IGF-II (10 ng/mL) + FSH, se añadieron a las proporciones de 0; 0,1; 1,0; 10; 50 y 100 (ng/mL). Las concentraciones de progesterona y estradiol producidos se midieron mediante radioinmuno-ensayo. Los datos obtenidos se sometireron a análisis de varianza. Los resultados obtenidos demuestran que el IGF-II, solo o IGF-II + FSH tuvieron efectos significativos (p

Epidermal growth factor (EGF) and transforming growth factor alpha (TGF-α) are structurally related growth factors that exert their biological actions by binding to the same cell-surface receptor, EGF receptor. However, in chicken cells, human EGF binds with approximately 100-fold lower affinity than human TGF-α. In a previous study, we localized EGF/TGF-α receptor immunohistochemically in the granulosa and theca of the developing follicles of laying hens. We have also shown that TGF-α binds to cell-surface receptors of the granulosa cells. The present study characterizes the nature of the EGF/TGF-α receptor. Immunoprecipitation of receptor proteins from cultured granulosa cells with an anti-EGF receptor antibody (12E) shows the expression of a 170-kDa receptor protein. The expression of the receptor protein decreases with follicular enlargement between the F3 and F1. Incubation of the cells with [125I]TGF-α followed by crosslinking with bis(sulphosuccinimidyl)suberate showed that TGF-α binds a similar (170 kDa) receptor protein immunoprecipitated with the 12E anti-EGF receptor antibody. The binding of TGF-α to granulosa cells caused receptor protein oligomerization, yielding the monomeric (170 kDa) and dimeric (340 kDa) protein forms. Oligomerization seemed to favour the formation of the dimeric rather than the monomeric form. Culturing granulosa cells with luteinizing hormone or follicle-stimulating hormone increased the expression of both monomer and dimer forms of the receptor proteins compared with the control. Western blotting analysis with anti-phosphotyrosine antibody revealed that the lysates of TGF-α-stimulated cells express phosphotyrosine-containing receptor proteins of 170 kDa and 340 kDa. The results show that chicken granulosa cells express the 170-kDa EGF=TGF-α receptor protein, which dimerizes on binding to TGF-α, suggesting that the receptor protein may be involved in the signal transduction of TGF-α actions in the chicken granulosa cells.

The presence of epidermal growth factor receptors (EGF-R) and the ligands epidermal growth factor/transforming growth factor-α (EGF/TGFα) have been reported in mammalian ovaries where they are implicated in folliculogenesis and steroidogenesis. Evidence is presented to show that authentic EGF/TGFα receptors are expressed by the avian granulosa cells. The TGFα receptors (TGFα-R) from chicken granulosa cells were characterized by specific binding of 125I-human TGFα. In this study, competition with human EGF, human TGFα, human IGF-I, human basic fibroblast growth factor (bFGF) and insulin for 125I-human TGFα binding demonstrated that the avian granulosa cell TGFα-R binds human EGF with 300-fold lower affinity than human TGFα. IGF-I, bFGF and insulin did not displace bound 125I-TGFα. Scatchard analysis showed that a single class of high-affinity binding sites is present on the granulosa cells (Kd 0·23 ± 0·009 nm). However, the number of binding sites altered during follicular maturation with a significant decline in the most mature follicle. These results go some way to explaining the basis for the changing sensitivity of avian granulosa cells to EGF/TGFα stimulation as they mature. In addition, the gonadotrophins, LH and FSH, increased the number of receptors in cultured granulosa cells and may therefore partially influence folliculogenesis and steroidogenesis through this route. Journal of Endocrinology (1996) 149, 171–179

The purpose of this study was to determine the presence of epidermal growth factor receptor and its potential ligands epidermal growth factor (EGF) and transforming growth factor alpha (TGF-alpha) in the tissues of the maturing follicles in the ovary of laying ISA-Brown hens using peptide-specific immunohistochemical methods. Cryostat sections, 6-8 microns thick, were made from fresh-frozen tissues of F1-F4 (largest to fourth largest) and large white follicles and they were immunostained for epidermal growth factor receptor, epidermal growth factor or transforming growth factor alpha using specific polyclonal antibodies. The EGF receptor and both ligands were detected in the granulosa, theca interna and theca externa layers of the follicles. The EGF receptor was localized both in the plasma membrane and cytoplasm of all cell types. EGF was predominantly cytosolic, whereas TGF-alpha was found in the plasma membranes and perinuclear areas of all cell types. The concentration of the receptor and both ligands decreased with follicular maturation. This observation is consistent with our previous observation that the response to EGF and TGF-alpha decreases as follicles mature, and thus provides further evidence that the receptor or the ligands may have a regulatory role in avian ovarian function.

A QTL located in the paternally expressed insulin-like growth factor 2 (IGF2) gene is known to increase muscle growth and reduce fat deposition in pigs. This makes the QTL in IGF2 a good marker for use in pig breeding programmes. However, care has to be taken as it is postulated that increased leanness and lowered fat deposition may have a negative effect on the prolificacy and longevity of sows. Selection of sire and dam lines for different alleles of the mutation in the paternally imprinted IGF2 gene could actually provide a solution to this problem. Therefore, in this study, the effect of the IGF2 QTL on prolificacy-related traits in sows was investigated. It was found that the paternal IGF2 wild-type allele was associated with higher reproduction performance in the sow. Moreover, it was also examined whether the difference in prolificacy in sows could be a consequence of differential IGF2 expression in the ovarian follicles of the sow or whether it is mainly a secondary effect caused by differences in fatness traits. Therefore, IGF2 expression was measured in follicles of different sizes from sows with different genotypes for the paternal IGF2 allele. It was observed that, however, while the size of the follicles was associated with follicular IGF2 expression level, the IGF2 genotype was not. It could be concluded that the difference in prolificacy of sows with a different paternal IGF2 genotype could be a secondary effect, resulting from differences in fat deposition.

Dimeric inhibins and activins are barely detectable in the plasma during prepubertal development of male and female chickens. This may be misconstrued to indicate that the proteins are not produced in the gonads and have no functional significance during this period. Very few studies have actually determined the mRNA expression profile of the inhibin and activin subunits in the gonads prior to puberty in order to establish their secretion at the local level and postulate potential roles for the inhibin and activins at this developmental stage. In this study, the expression of the mRNA for the alpha-, betaA-, and betaB-subunits was determined in the ovary and testis of chickens during prepubertal development. Gene expression was determined at 3, 5, 6, 8, 10, 12, 16, and 18 weeks of age by RT-PCR. Messenger RNA level was quantified by competitive RT-PCR at 3, 6, 12, and 18 weeks of age in order to detect any changes with development, suggest potential relationship to the profile of dimeric inhibins and activins reported previously and to suggest potential paracrine and endocrine roles for them. The results show that all the inhibin/activin subunit mRNAs are expressed in the testis of the chicken throughout the period of prepubertal development up to 18 weeks of age. However, in the ovary, only the betaA- and betaB-subunits were detected at all ages whereas the alpha-subunit mRNA could only be detected just before puberty. Quantification of the mRNA levels showed variation of each subunit with age. These temporal changes suggest relationship with paracrine functional role in the ovary or the testis. Quantitative changes in expression levels also suggests that there may be some relationship between mRNA levels and the type and amount of dimeric inhibins and activins produced at any developmental stage. There are major differences between the male and female gonads in the timing of the expression of different subunits. In conclusion, the expression of the mRNA subunits in the testis and ovary suggests that inhibins and activins are being produced but may be principally involved in autocrine/paracrine function within the gonads.

Epidermal growth factor (EGF) and transforming growth factor alpha (TGF-alpha) are structurally related growth factors that exert their biological actions by binding to the same cell-surface receptor, EGF receptor. However, in chicken cells, human EGF binds with approximately 100-fold lower affinity than human TGF-alpha. In a previous study, we localized EGF/TGF-alpha receptor immunohistochemically in the granulosa and theca of the developing follicles of laying hens. We have also shown that TGF-alpha binds to cell-surface receptors of the granulosa cells. The present study characterizes the nature of the EGF/TGF-alpha receptor. Immunoprecipitation of receptor proteins from cultured granulosa cells with an anti-EGF receptor antibody (12E) shows the expression of a 170-kDa receptor protein. The expression of the receptor protein decreases with follicular enlargement between the F3 and F1. Incubation of the cells with [125I]TGF-alpha followed by cross-linking with bis(sulphosuccinimidyl)suberate showed that TGF-alpha binds a similar (170 kDa) receptor protein immunoprecipitated with the 12E anti-EGF receptor antibody. The binding of TGF-alpha to granulosa cells caused receptor protein oligomerization, yielding the monomeric (170 kDa) and dimeric (340 kDa) protein forms. Oligomerization seemed to favour the formation of the dimeric rather than the monomeric form. Culturing granulosa cells with luteinizing hormone or follicle-stimulating hormone increased the expression of both monomer and dimer forms of the receptor proteins compared with the control. Western blotting analysis with anti-phosphotyrosine antibody revealed that the lysates of TGF-alpha-stimulated cells express phosphotyrosine-containing receptor proteins of 170 kDa and 340 kDa. The results show that chicken granulosa cells express the 170-kDa EGF/TGF-alpha receptor protein, which dimerizes on binding to TGF-alpha, suggesting that the receptor protein may be involved in the signal transduction of TGF-alpha actions in the chicken granulosa cells.

The effects of insulin-like growth factor I (IGF-I), alone, and in combination with LH or transforming growth factor alpha (TGF-alpha), on replication and progesterone production by cultured avian granulosa cells obtained from the three largest (F1-F3) follicles were studied. IGF-I and TGF-alpha stimulated proliferation of granulosa cells in a dose-dependent manner, and responsiveness decreased as the cells matured. IGF-I stimulated progesterone production from granulosa cells of all the follicles with no change in ED50 value during follicular maturation; however, the maximum response was from cells derived from F1 follicles. IGF-I plus LH had an additive effect on progesterone production by cells from all follicles. In contrast, TGF-alpha inhibited basal and LH- and IGF-I-stimulated progesterone production. These data show that IGF-I and TGF-alpha may interact with each other during granulosa cell maturation, such that efficacy of IGF-I increases, while that of TGF-alpha decreases before ovulation. Furthermore, both growth factors interact with LH, either to enhance or inhibit progesterone production by granulosa cells. However, LH, IGF-I and TGF-alpha combine to stimulate proliferation of granulosa cells.