Reproduction and Physiology
Carcass and reproductive data including scan weight, ribeye area, rump fat, 12-13th rib fat and percentage intramuscular fat and reproductive tract scores (RTS) at 344 days were collected on 180 1998-born and 70 1999-born Angus heifers to determine the relationship between these traits. 1998-born heifers with higher RTS tended to be heavier and have more rump fat at 405 days (P < .05). Heavier heifers and heifers with more rump fat had higher RTS when adjusted to 395 days (P < .05). 1999-born heifers showed a similar pattern, with heavier heifers having higher RTS (P < .05). Rump fat was not as significant for 1999-born heifers compared with 1998-born heifers. Heavier heifers with more rump fat are more likely to have more mature reproductive tracts at breeding.
Iowa State University
Minick, Jennifer A.; Wilson, Doyle E.; Rouse, Gene H.; Hassen, Abebe; Pence, Mel; Sealock, R.; and Hopkins, Steven, "Relationship between Body Composition and Reproduction in Heifers" (2002). Beef Research Report, 2001. 35.