The evolution of the flower is commonly thought to have spurred angiosperm diversification. Similarly, particular floral traits might have promoted diversification within specific angiosperm clades. We hypothesize that traits promoting the precise positional transfer of pollen between flowers might promote diversification. In particular, precise pollen transfer might produce partial reproductiv...

Breeding objectives were developed for Targhee sheep under rangeland production conditions. Traits considered were those for which EPD were available from the US National Sheep Improvement Program and included direct and maternal effects on 120-d weaning weight (WW and MM, respectively); yearling weight (YW); yearling fleece weight, fiber diameter, and staple length; and percent lamb crop (PLC)...

Objective: The aim of the present study was to evaluate artificial insemination techniques on reproductive performance in Ghezel ewes synchronized with CIDR during breeding season. Methods: All ewes were treated with controlled internal drug release device (CIDR) inserted into the vagina of the ewes for 14 days. All ewes were treated a single intramuscular (IM) dose of PMSG was injected. In thi...

Performance of Dorper sheep was compared to other breeds in pure and cross-breeding evaluations under different production systems. The number of ewes lambed per ewe joint (E(L)/E(J)) varied for the Dorper from 0.68 to 0.91 (average 0.81) and for other breeds and crosses from 0.65 to 0.91 (average 0.82). Average litter size (L(B)/lambing) varied from 1.02 to 1.52 (average 1.28) and from 1.02 to...

Context Proximity sensors were used recently to determine the maternal pedigree of lambs on a small plot with high accuracy. If this accuracy is maintained under commercial grazing conditions, method could be useful alternative improving genetic gain in sheep, including reproduction traits. Aims To investigate using proximity and define level interactions required confidently irrespective diffe...

genetic selection to improve economically important traits. Most recently, much of that progress has been through the implementation of expected progeny differences (EPDs). Expected progeny differences make it possible to compare the genetic merit of two or more animals for any number of traits. Most EPDs involve growth or carcass traits, because most producers are paid by the pound, or in some...

It has been hypothesized that a high reproductive output contributes to the unique gigantism in large dinosaur taxa. In order to infer more information on dinosaur reproduction, we established allometries between body mass and different reproductive traits (egg mass, clutch mass, annual clutch mass) for extant phylogenetic brackets (birds, crocodiles and tortoises) of extinct non-avian dinosaur...

Tuj sheep, a well adopted breed for the geography and climate of the highlands, originated in the Caucasus and are found throughout the northeast of Turkey. Although the mature sheep are able to reproduce normally at these conditions, ewe-lambs are normally not able to reach puberty during the first year of their life. Shortage in feed due to long and cold winters together with the seasonality ...

Unlike most domestic livestock species, sheep are widely known as an animal with marked seasonality of breeding activity. The annual cycle of daily photoperiod has been identified as the determinant factor of this phenomenon, while environmental temperature, nutritional status, social interactions, lambing date and lactation period are considered to modulate it. The aim of this paper is to revi...

The remarkable diversity of male reproductive traits observed in nature is often attributed the 2 1 evolutionary forces of sexual conflict, sperm competition, and sperm precedence 1-4. However, the genetic 2 2 mechanisms that enable reproductive traits to respond to changes in selective regime are often unknown. 2 3 Moreover, because most genes expressed in reproductive organs (e.g. testes) are...