Functional traits: cell count (-0.5), ease of birth, ease of calving, fertility (-0.5), functional longevity, milking speed (-0.5).
Functional traits: cell count (0.2), ease of birth, ease of calving, fertility (0), functional longevity, milking speed (-1), temperament.
It is also possible that early experience affected factors that influence birth ease (e.g. disproportionate fetus size, uterine activity) with knock-on effects on pain responses, although lamb birth weights did not differ between treatments.
A new study in mice shows that a mother's immune system calls on a special set of cells to protect her growing fetus and these cells linger long after birth to ease the way for a subsequent pregnancy.
These contained information about age and pedigree of heifer, insemination dates and pedigree of bull, calving date, single or twin birth, calving ease (1 = easy, 2 = normal, 3 = difficult), attitude of calf, status of cow after calving and retained placenta.
Details concerning support and magnitude of effect for each QTL associated with birth weight, calving ease direct, calving ease maternal, carcass weight, marbling, mature weight, ribeye muscle area, weaning weight direct, weaning weight maternal, yield grade and yearling weight in all ten cattle breeds are in Additional files 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 and 12, respectively.
Angus cattle have recently been selected to reduce birth weights to ease dystocia [ 34].
A pleiotropic QTL on BTA5 at 48 – 50 Mb associated with birth weight, calving ease direct, marbling and ribeye muscle area was identified in Brangus.
A pleiotropic QTL on BTA2 at 6 Mb associated with birth weight, calving ease direct, marbling, rib eye area, weaning weight direct, weaning weight maternal, and yield grade was identified in Limousin.
However, the unadjusted significant SSR associations for the Charolais and Limousin breeds were positioned near or located at the same positions as previously reported QTL associated with maternal calving ease, birth weight, or calf size on chromosomes 3 and 2, respectively [ 13, 29, 35, 36].
The QTL on BTA7 at 93 Mb is pleiotropic and associated with birth weight, calving ease direct and maternal in Angus and Hereford; carcass weight in Angus and Simmental; mature weight in Hereford; ribeye muscle area in Angus, Gelbvieh, Hereford, Red Angus and Simmental; weaning weight direct and yearling weight in Angus, Hereford and Simmental.
