Porcupines are sexually active throughout the estrous cycle, and sexual behavior is not affected by the reproductive status and hormonal milieu of females. Increased female-male interactions during estrus are the only indications of behavioral changes during estrus. The lack of aggression shown by females to known males as opposed to aggression shown to strange males, the greater interest shown...

Our understanding of how male seminal fluid proteins (SFPs) influence the outcome of copulation in a wide range of insect taxa has been fueled primarily by studies of Drosophila (1). SFPs are known to localize, after copulation, to specific regions of the female reproductive tract and nervous system. Manipulative studies revealed that these proteins control a number of postcopulatory processes,...

Sexual reproduction likely evolved as protection from environmental stresses, specifically, to repair DNA damage, often via homologous recombination. In higher eukaryotes, meiosis and the production of gametes with allelic combinations different from parental type provides the side effect of increased genetic variation. In fungi it appears that while the maintenance of meiosis is paramount for ...

Genetic improvement in reproductive efficiency through selection is difficult because many reproductive traits are binomial and have low heritabilities. Before genetic markers can be generated for fertility in cows, greater characterization of reproductive phenotypes is needed to understand the components of the trait. The current study tested the hypotheses that: 1) breeds vary in postpartum i...

This study aimed to determine the reproductive characteristics of Saanen goats Australian origin using an estrus synchronization program with hormones (MPA and PMSG) in two different mating periods (Period I Period II) investigate survival rates growth performances kids. According results research, it was determined that pregnancy rate litter size were higher period (87% 2.16) compared II (80.5...

Embryo transfer is a multi-step process that involves the production and collection of preimplantation embryos from genetically superior females (called donors) and the subsequent transfer of the harvested embryos into reproductively healthy females (called recipients) for the purpose of establishing pregnancies and producing live offspring. The first successful embryo transfer in mammals was p...

The widespread occurrence of sexual organisms despite the high costs of sex has long intrigued biologists. The best-known costs are the twofold cost of producing males and the cost associated with producing traits to attract mates and to interact with mating partners, such as exaggerated sexual behaviors and morphological modifications. These costs have been inferred from studies of plants and ...

This study was conducted to investigate the effect of different estrus synchronization protocols followed by artificial insemination on response and conception rate Abergelle goats. Three protocols: (i) standard protocol associating progestogens, gonadotropins prostaglandins (P4 + eCG PGF2?), (ii) single injection prostaglandin (PGFS), (iii) double (PGFD) were evaluated compared a control group...

to investigate the igg content and its variations in uterine fluid (uf) during the estrous cycle of the cow and to compare them with those of the blood serum (s), six pairs of serum and uf samples for each phase of the cycle selected out of 240 bovine genital tracts and blood samples were collected from urmia abattoir. the uf samples were collected by gentle scraping of the endometrium using a ...