Since the early 60s, in our lab we sought useful correlations of seminal traits and fertility in order to ultimately predict the reproductive outcome of bovine semen used in artificial breeding or the fertility of a specific male under natural service. Despite these efforts, to this day we can only account for approximately 50-60% of the variation in fertility among males by measuring seminal t...

Introduction: Since the early 60s, in our lab we sought useful correlations of seminal traits and fertility in order to ultimately predict the reproductive outcome of bovine semen used in artificial breeding or the fertility of a specific male under natural service. Despite these efforts, to this day we can only account for approximately 50-60% of the variation in fertility among males by measu...

Economic weights have been estimated in two breeds (Latxa and Manchega) using economic and technical data collected in 41 Latxa and 12 Manchega dairy sheep flocks. The traits considered were fertility (lambing per year), prolificacy (number of lambs), milk yield (litres) and longevity (as productive life, in years). A linear function was used, relating these traits to the different costs in the...

Grain number per spike, which is greatly influenced by floret fertility, is an important trait of wheat (Triticum aestivum L.) yield. Maximum floret primordia, fertile floret, and final grain number per spikelet are three crucial factors of floret fertility. Floral degradation plays a critical role in determining these three floret fertility-related traits. Twelve hexaploid spring wheat genotyp...

The objective of this study was to quantify the genetic association of body energy assessed throughout lactation with a cow's fertility. Nine direct and indirect body energy traits were defined at different stages of lactation. Four were daily records of energy balance, energy content, cumulative effective energy (CEE) and body condition score (BCS) calculated between lactation days 4 and 311. ...

'Demographic transition theory' assumes that fertility decline is irreversible. This commonly held assumption is based on observations of recent and historical reductions in fertility that accompany modernization and declining mortality. The irreversibility assumption, however, is highly suspect from an evolutionary point of view, because demographic traits are at least partially influenced by ...

Body condition score (BCS) records of primiparous Holstein cows were analyzed both as a single measure per animal and as repeated measures per sire of cow. The former resulted in a single, average, genetic evaluation for each sire, and the latter resulted in separate genetic evaluations per day of lactation. Repeated measure analysis yielded genetic correlations of less than unity between days ...

The Effect of Different Sources Selenium and Microencapsulation on Fertility Hatching Traits in Arbor Acres Broiler Breeder

The differences of fertility and prolificacy traits for Rahmani and Chios ewes were studied in this investigation. The study was conducted during two consecutive years that included three lambing season with a total of 273 ewes (162 Rahmani and 111 Chios) bred, 230 ewes lambing, 280 lambs born and 237 lambs weaned. Breed of ewes had a significant effect on fecundity, lambing rate and weaning ra...

Detailed biological analyses (e.g. epidemiological, genetic) of animal health and fitness in the field are limited by the lack of large-scale recording of individual animals. An alternative approach is to identify immune traits that are associated with these important functions and can be subsequently used in more detailed studies. We have used an experimental dairy herd with uniquely dense phe...