A study is described which is unique in that resistance to each of the major diseases which affect production in Merino sheep was measured in the same flock under the same environmental conditions. Results indicated that within the one flock, genetic variation exists for resistance to internal parasites, foot-rot, fleece rot and dermatophilosis. Heritability estimates were similar to those publ...

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)...

The objective was to determine appropriate analytical models considering cytoplasmic inheritance for birth weight (BWT, n = 35,604), weaning weight (WWT, n = 34,114), fleece weight (FWT, n = 38,113) and number born (NB, n = 39,029) for Rambouillet sheep. For BWT, models that included dam by year, dam by number born, and sire by dam effects, in addition to direct and maternal effects, were signi...

The total genome sequence of the archaeon Methanococcus jannaschii completes the trilogy of genomes for the three domains of life-Archaea, Bacteria and Eucarya. It will have far-reaching consequences for evolutionary studies and for the way in which experimental biology is performed.

The objective was to describe genetic parameters and genetic changes in litter sizes at birth and weaning (LB and LW, n =9081), birth weight (BW, n =11,896), weaning weight (WW, n =11,104), fleece weight and grade (FW and FG, n =8872), and staple length (SL, n =1805) of Polypay sheep. Direct heritability estimates from single-trait analyses were 0.11 for LB, 0.02 for LW, 0.17 for BW, 0.18 for W...

This study reports the phenotypic trends for wool, growth, and reproductive traits in mixed-age ewes after twenty years of genetic selection. Data were obtained from Merino nucleus flock Uruguay between 1999 2020. Overall, aim this selection was to reduce fiber diameter (FD) increase both clean fleece weight (CFW) live (LW). on ewe wool traits, LW, body condition score (BCS), total number lambs...

The ability to maintain weight during adverse seasons is an important characteristic in mature ewes. Ewes that lose less weight will be in better condition at mating and throughout pregnancy resulting in higher fertility, fecundity and lamb survival, and lower ewe mortality. Liveweight data (corrected for greasy fleece and conceptus weights) from mature Merino ewes was analysed to determine fac...