Effects of Supplemental Fat on Beef Cow and Heifer Performance, Lactation and Reproduction

The objective of this research was to evaluate the effects of supplemental fat on beef cow and heifer performance, lactation and reproduction. Supplemental fat sources, differing in fatty acid composition, were evaluated to determine the effects on performance, lactation and reproduction in Angus x Simmental cows (Exp. 1) or heifers (Exp. 2). Feeding supplemental fat (soybeans, flaxseed, and animal fat) did not affect (P &ge; 0.05) cow BW or BCS. There were also no differences (P &ge; 0.05) among the fat sources. But, in heifers, fat supplementation increased (P < 0.05) ADG, with the flaxseed resulting in higher (P &le; 0.05) ADG than the soybeans. Feeding supplemental fat did not affect ( P &ge; 0.05) cow milk production or calf ADG. Supplemental fat increased (P &le; 0.05) cow milk fat percent and yield with the soybeans resulting in higher (P &le; 0.05) fat content than flaxseed or animal fat. Feeding supplemental fat did not affect (P &ge; 0.05) reproductive performance compared to control supplement in cows. However, soybean supplementation resulted in poorer (P &le; 0.05) conception to the clean-up bulls and overall pregnancy rates in cows compared to flaxseed. In heifers, the fat supplementation resulted in lower ( P &le; 0.10) overall conception rates. Feeding soybeans resulted in higher (P &le; 0.05) AI conceptions in heifers compared to flaxseed. Simmental cows were used in four experiments to compare the effects of dry distillers grains with solubles (DDGS) and corn gluten feed (CGF) on cow performance, lactation and reproduction. Cows fed DDGS had improved (P &le; 0.10) BW gain compared to cows fed CGF in 3 of the 4 trials. Feeding DDGS resulted in lower ( P &le; 0.10) milk production than CGF in 3 of the 4 trials and lower (P &le; 0.10) calf ADG in 2 of the 4 trials. Feeding DDGS lowered (P &le; 0.10) milk protein yield in 3 of the 4 trials. There were no differences (P &ge; 0.05) in reproductive performance in any of the trials comparing DDGS and CGF. Feeding DDGS repartitioned nutrients from milk production to cow weight gain.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Animal Sciences

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2015

Author dc:creator

• Shike, Daniel William

Contributors dc:contributor

• Faulkner, Dan B.

• Agriculture, Animal Culture and Nutrition

Language dc:language

eng

Identifier

(MiAaPQ)AAI3290376

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/83606