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The undifferentiated spermatogonial population in mammalian testes contains a spermatogonial stem cell (SSC) population that can regenerate continual spermatogenesis following transplantation. This capacity has the potential to be exploited as a surrogate sires breeding tool to achieve widespread dissemination of desirable genetics in livestock production. Because SSCs are relatively rare in testicular tissue, the ability to expand a population in vitro would be advantageous to provide large numbers for transplantation into surrogate recipient males. Here, we evaluated conditions that would support long-term in-vitro maintenance of undifferentiated spermatogonia from a goat breed that is endemic to Kenyan livestock production. Single-cell suspensions enriched for undifferentiated spermatogonia from pre-pubertal bucks were seeded on laminin-coated tissue culture plates and maintained in a commercial media based on serum-free composition. The serum-free media was conditioned on goat fetal fibroblasts and supplemented with a growth factor cocktail that included glial cell line-derived neurotrophic factor (GDNF), leukemia inhibitory factor (LIF), stromal cell-derived factor (SDF), and fibroblast growth factor (FGF) before use. Over 45 days, the primary cultures developed a cluster morphology indicative of in-vitro grown undifferentiated spermatogonia from other species and expressed the germ cell marker VASA, as well as the previously defined spermatogonial marker such as promyelocytic leukemia zinc finger (PLZF). Taken together, these findings provide a methodology for isolating the SSC containing undifferentiated spermatogonial population from goat testes and long-term maintenance in defined culture conditions.
RESUMO
This study aimed at testing the efficacy and safety of Dacryodes edulis plant parts in diets fed to chicken. The plant has potential for use as a natural prebiotic to substitute the conventionally used antibiotic growth promoters in poultry production. Phytochemical analyses of the plant leaves, stem, and bark combination (stembark) and seed powders from the D. edulis were carried out. The powder from the three D. edulis plant parts were used as supplement in formulating six experimental diets tested in this study. The diets were TL0Ed (0.5% leaves powder), TL1Ed (1.0% leaves powder), TB0Ed (0.5% stembark powder), TB1Ed (1.0% stembark powder), TS0Ed (0.5% seeds powder), and TS1Ed (1.0% seeds powder). Besides, a positive (T+ positive control; 0.5-g oxytetracycline as recommended by the manufacturer) and a negative (T- negative control; having no commercial antibiotic and no plant supplement) diets were prepared for comparison purposes. The diets were fed to a total of 288 dual-purpose chicken for a period of 14 weeks. The chicken growth and body composition characteristics, blood chemistry, and microbiota count were collected and used as indicators of the plant parts efficacy and safety. The analysis of the D. edulis plant parts significantly differed (P ≤ 0.05) in their phytochemical contents. The initial body weight and feed conversion efficiency ratios were not significantly different (P ≥ 0.05) between and among treatment groups. However, significant differences (P ≤ 0.05) were detected in the feed intake and body weight gain at eighth week. Live weight at eighth week was significantly different (P ≤ 0.05) with its values ranging between 503.32 and 614.93 g for treatments TL1Ed and TNeg-, respectively. The dietary treatment of D. edulis leaves, stembark, and seed powder at the two inclusion levels significantly (P ≤ 0.05) decreased the colonies forming unit of Escherichia coli and Salmonella sp. as compared with negative control treatment in the eighth week phase. The level of glucose, total cholesterol, triglycerides, aspartate aminotransferase, alanine amino transferase, alkaline phosphatase, and the packed cell volume did not differ significantly (P ≥ 0.05) between and among dietary D. edulis treatments. The findings from this research provide crucial information on the efficacy and safety of D. edulis plant parts. This is an important step in testing the potential of the plant in use as a prebiotic in chicken feeds production.
RESUMO
[This corrects the article DOI: 10.1371/journal.pone.0225084.].
RESUMO
Rwanda has about 4.5 million of indigenous chicken (IC) that are very low in productivity. To initiate any genetic improvement programme, IC needs to be accurately characterized. The key purpose of this study was to ascertain the genetic diversity of IC in Rwanda using microsatellite markers. Blood samples of IC sampled from 5 agro-ecological zones were collected from which DNA was extracted, amplified by PCR and genotyped using 28 microsatellite markers. A total of 325 (313 indigenous and 12 exotic) chickens were genotyped and revealed a total number of 305 alleles varying between 2 and 22 with a mean of 10.89 per locus. One hundred eighty-six (186) distinct alleles and 60 private alleles were also observed. The frequency of private alleles was highest in samples from the Eastern region, whereas those from the North West had the lowest. The influx of genes was lower in the Eastern agro-ecological zone than the North West. The mean observed heterozygosity was 0.6155, whereas the average expected heterozygosity was 0.688. The overall inbreeding coefficient among the population was 0.040. Divergence from the Hardy-Weinberg equilibrium was significant (p<0.05) in 90% of loci in all the populations. The analysis of molecular variance revealed that about 92% of the total variation originated from variation within populations. Additionally, the study demonstrated that IC in Rwanda could be clustered into four gene groups. In conclusion, there was considerable genetic diversity in IC in Rwanda, which represents a crucial genetic resource that can be conserved or optimized through genetic improvement.