|Loyd, Andrea - Texas A&M University|
|Vann, Rhonda - Mississippi State University|
|Banta, Jason - Texas A&M University|
|Welsh Jr, Thomas - Texas A&M University|
|Carroll, Jeffery - Jeff Carroll|
|Randel, Ronald - Texas A&M University|
Submitted to: Journal of Animal Science
Publication Type: Abstract Only
Publication Acceptance Date: 2/25/2011
Publication Date: 8/11/2011
Citation: Loyd, A.N., Vann, R.C., Banta, J.P., Welsh Jr, T.H., Carroll, J.A., Randel, R.D. 2011. Effects of transportation and lipopolysaccharide (LPS) challenge on body weight and feed intake of crossbred heifers [abstract]. Journal of Animal Science. 89:497(E-Suppl. 1).
Technical Abstract: An experiment was conducted to examine the effects of transportation and LPS challenge on feed intake (FI) and body weight (BW) of calves. Brahman x British heifers (n=44) from Raymond, MS, were weaned and acclimated to a high roughage diet fed in GrowSafe® bunks for 25 d. Heifers were blocked by BW and breed and randomly assigned to a transportation treatment group: transport (Trans; n=14); no transport with access to feed and water (Feed; n=15); and no transport without access to feed and water (NoFeed; n=15). Trans heifers were loaded onto a 7.3 m livestock trailer, Feed heifers were returned to the GrowSafe® bunks, and NoFeed heifers were placed in a dry-lot. Transport ensued for 12 h before Trans heifers were unloaded in Overton, TX. Trans and NoFeed heifers were then allowed access to hay and water for 6.5 h. Trans heifers were loaded onto the trailer and transported for 12 h back to MS. During this time, NoFeed heifers were restricted from feed and water. Feed heifers had continual access to feed and water throughout the study. Following transport, all heifers returned to the GrowSafe® bunks for 12 h with ad libitum access to feed and water. Heifers were then injected subcutaneously with LPS (0.5 micrograms/kg BW; n=22) or saline (4.5 microliters/kg BW; n=22). BW was recorded prior to transport, after the second transport, prior to LPS challenge, and 24 and 48 h post-LPS. Daily FI was monitored when heifers had access to GrowSafe® bunks. During the 12-h post-transport period, NoFeed heifers had greater (P<0.01) FI than Trans heifers, which had greater (P<0.01) FI than Feed heifers (8.5, 5.9 and 2.4 kg). Post-LPS FI did not differ among treatments (P>0.10). During the transport period Trans and NoFeed heifers lost more BW (P<0.01; -34.4 and -25.9 kg) than Feed heifers (1.21 kg); BW change was not different (P>0.20) between NoFeed and Trans heifers. Change in BW from pre- to 24 h or 48 h post-LPS was not different (P>0.20). These results suggest that shrink observed in transported calves is likely the result of feed and water withdrawal. However, stress associated with transport may hinder FI immediately following transport.