The global proteome of sperm and seminal plasma of fertile stallions was investigated to determine whether associations with relative in vivo fertility exist. Seven stallions at stud in a commercial breeding station were collected throughout the breeding season and bred to a total of 164 mares to determine conception rates. On three occasions during the breeding season, raw semen was obtained f...

A central goal of population ecology is to identify the factors that regulate population growth. Monarch butterflies (Danaus plexippus) in eastern North America re-colonize the breeding range over several generations that result in population densities that vary across space and time during the breeding season. We used laboratory experiments to measure the strength of density-dependent intraspe...

This study was conducted at the grasscutter section of the University of Education, Winneba, Ghana, to estimate effects of non-genetic factors on growth traits. Data consisted of records of 502 kids born from 136 does and 40 sires from 2006 to 2010. Feed intake increased (P<0.01) with increasing parity and years, whilst feed efficiency declined (P<0.01) with years. Animals consumed less (P<0.01...

The goal of this work was to correlate oxidative stress caused by reactive oxygen species (ROS) and DNA damage with classic semen parameters in spermatozoa and seminal plasma of fertile and subfertile stallions. Oxidation was measured in both lipids and proteins, using the thiobarbituric acid reactive species (TBARS) assay and the DNPH carbonyl groups assay, respectively. Sperm DNA damage was m...

In order to elucidate the relationship between androgens and the function of the muskrat (Ondatra zibethicus) scented glands during the breeding season, we investigated immunolocalization of steroidogenic enzymes P450scc, 3βHSD and P450c17 in the muskrat testes and scented glands. Nine adult muskrats were obtained in March (n=3), May (n=3) and July (n=3) 2010. Steroidogenic enzymes were immunol...

It is proposed that where sexually selected vocal communication is an honest signal, the call production rate is predicted to change throughout the breeding season. Male leopard seals call underwater for many hours each day over their three- to four-month breeding season, and it is hypothesized that a decrease in calling rate would be associated with the declining body condition of smaller male...

Alternative mating tactics in males of various taxa are associated with body color, body size, and social status. Chameleons are known for their ability to change body color following immediate environmental or social stimuli. In this study, we examined whether the differential appearance of male common chameleon during the breeding season is indeed an expression of alternative mating tactics. ...

A total of 1474 and 1935 production and reproduction records of crossbred cattle and Murrah buffaloes from the year 1992 to 2012 were utilized in the present study to investigate breeding efficiency (BE) and various performance traits. Breeding efficiency was calculated using Wilcox and Tomar methods and Least –squares of Harvey model was used to study the effects of various non-genetic factors...

Timing of reproduction in a seasonal cycle is a life history trait with important fitness consequences. Capital breeders produce offspring from stored resources and, by decoupling feeding and reproduction, may bend the constraints caused by seasonality in food or predation. Income breeders, on the other hand, produce offspring from concurrent food intake, with the disadvantage of less flexibili...

The BLRI Cattle Breed 1(BCB-1) is a native cattle breed developed by Bangladesh Livestock Research Institute (BLRI) through selective breeding among indigenous cattle of Bangladesh. Data asserted from record sheets of 529 animals maintained during 1992 to 2006 were analyzed to evaluate the reproductive efficiency of BCB-1 cattle in different generations, seasons and parities. The highest percen...