Insulin-like growth factor-1 gene (IGF-1) is considered as a major candidate gene for the economic traits of animal production. Polymorphism of 5′ flanking region of IGF-1 gene in Barki sheep (n = 91) and its association with wool traits were studied using the polymerase chain reaction coupled with single-strand conformation polymorphism technique (PCR-SSCP), PCR-restriction fragment length polymorphism (PCR-RFLP), sequence analysis and different measurements of wool traits (clean fleece weight and fiber diameter). PCR-SSCP analysis revealed three different banding patterns corresponding with three genotypes frequencies GG (0.25), GA (0.58), AA (0.17). PCR-RFLP and corresponding sequence analysis revealed nucleotide transversion from Guanine (G) to Cytosine (C) at nucleotide position 85 and transition from (G) to Adenine (A) at position 87. This is the first study that recorded two SNPs within the 5′ flanking region of IGF-1 gene in Egyptian Barki sheep, which were submitted to DNA Data Bank OF Japan (DDBJ) with Accession No. LC151463.1. The genotype GG showed positive significant association (P < 0.001) with clean fleece weight (CFW) trait (Odd Ratio = 2.83). By contrast, genotype AA had negative significant association (P < 0.05) with such trait (Odd Ratio = 0.15). On the other hand, fiber diameter (FD) measurements showed no significant association (P > 0.05) with different IGF-1 genotypes. This study adds evidence of the association between IGF-1 gene polymorphism and CFW of wool in Egyptian Barki sheep. Therefore; it is important to consider IGF-1 gene as a candidate gene marker for wool weight traits and it should be identified before using successful breeding program.

Genetic information especially of the Quantitative Trait Loci (QTL) which affect different performance traits is considered one of the most effective tools in the breeding programs of livestock. Several genes were reported as candidate genes that effect litter size performance and one of these genes is the KISS1 which is considered as a regulator of puberty onset. The polymorphisms of KISS1 gene have some relationships with high prolific and sexual precocity. The objective of this study was the detection of the restriction fragment length polymorphism (RFLP) and single nucleotide polymorphisms (SNPs) of KISS1 gene in six major Egyptian small ruminant breeds. The primers used in this study flanked a 377 bp fragment from intron 1 of KISS1 gene in sheep and goat. These PCR amplified fragments were digested with XmnI endonuclease. According to the presence or absence of the restriction site (GAANN^NNTTC) at position 121^122, we genotyped the 122 tested animals as AT (54.92%) and TT (45.08) with the absence of AA genotype. The overall frequencies of alleles A and T were 27.46 and 72.54%, respectively. The sequence analysis of purified PCR products representing these two detected genotypes declared the presence of a SNP (T→A) at position 125 in the amplified fragment which is responsible for the elimination of the restriction site and consequently the presence of two different alleles T and A. The nucleotide sequences of sheep KISS1 alleles T and A as well as goat KISS1 alleles T and A were submitted to GenBank database and have accession numbers: KP835797, KP835798, KP835799 and KP835800, respectively. It is concluded that small ruminant breeds have high frequency of KISS1 allele T which was associated with greater litter size. We recommend to increase this allele in Egyptian small ruminant breeds and also to select the animals which possess TT genotypes of KISS1 gene and enter them in breeding programs of Egyptian small ruminants to increase their fecundity traits.

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SummaryThe present study was carried out in order to evaluate the mutagenic effect of 3 nitrogenous fertilizers; urea, ammonium nitrate and calcium nitrate; on Drosophila melanogaster. Newly hatched larvae were treated with the LC 25 and LC 50 of the 3 tested nitrogenous fertilizers. The classic sex-linked recessive lethal (SLRL) test was used to detect the differential mutagenic effect of the fertilizers on the 3 germ stages. The results showed that all fertilizers exhibited variable mutation frequencies in the different broods of spermatogenesis after a single treatment. Urea exhibited a direct mutagenic effect on post-meiotic stages whereas ammonium nitrate and calcium nitrate revealed an indirect mutagenic effect on meiotic and pre-meiotic stages. The electrophoretic separation of proteins (SDS-PAGE) showed that treatment with these fertilizers resulted in polymorphetic changes in different low and high molecular weight protein bands, causing alteration in the electrophoretic patterns and densities of proteins. This study showed that the tested nitrogenous fertilizers possess mutagenic potentialities which are related to their nitrogen content.

Aim: The present work was carried out to study the genetic characteristics of the IGFBP-3 gene in buffaloes reared in Egypt, where it is considered as one of the important molecular markers for productivity traits like growth and immunity in livestock species. One-hundred animals were used in this research work. Methods: The studied gene was amplified through polymerase chain reaction technique. Afterwards, the amplified fragment at 651-bp was digested with three different endonucleases; HaeIII, MspI, and TaqI. The genetic character of the IGFBP-3 gene was studied by using PCR-RFLP and nucleotide sequencing. Results: The PCR products after the digestion with those restriction enzymes revealed that the presence of the following fragments: two fragments at 506-and 145-bp with MspI two fragments at HaeIII. The restriction digestion of the amplified fragments of the IGFBP-3 gene did not show a