Does rest time impact calf growth performance?
By Britt Hicks
Beef cattle are exposed to stress at multiple points throughout their life. Transportation is generally regarded as stressful to cattle, particularly for feeder calves.1,2,3
Some stresses, like transportation, are unavoidable. Transportation of cattle in the United States occurs in many facets such as movement through livestock auctions, to feedlots, and eventually to processing facilities. Thus, cattle may be transported several times in their lifetime.
The stress induced from transport can predispose calves to dehydration, reduced feed intake, inhibition of immune function and increased susceptibility to bovine respiratory disease (BRD).4
Many methods have been adopted to decrease the severity of transport stress in newly received cattle. Preconditioning cattle by ensuring adequate weaning time prior to transport, vaccinating, castrating, dehorning and treating with anthelmintics has been proven extremely effective.5
Delaying processing upon arrival to a feedlot might also counteract the stress associated with transport. Once received by a feedlot, cattle are typically placed into a receiving pen and allowed to rest, which is then followed by processing and placement into feedlot pens.6
Kansas State University research evaluated the impact a post-transport rest period had on calf growth performance, mortality and morbidity.7 This study also aimed to determine if a rest period affected calf response to anthelmintics and blood serum metabolites.
In this study, 80 crossbred heifers (551 pound initial weight) were transported approximately 300 miles from an Oklahoma City, Oklahoma sale barn to the Kansas State University Beef Cattle Research Center (Manhattan, Kansas) via semi-truck, with a total transit time of approximately six hours. The heifers were considered high-risk and originated from a geographic area high in parasites.
Upon arrival, the heifers were unloaded and randomly placed into one of four receiving pens and provided ad libitum hay and water. Each pen (20 heifers/pen) was randomly assigned to one of four treatments of varying rest times before processing:
Processing was considered day 0 for the trial. After all cattle were processed, heifers were allotted into individual pens with ad libitum access to a receiving ration and water.
At processing, all heifers were tagged, weighed and subcutaneously injected with Cydectin (Bayer Animal Health) and orally dosed with Synanthic (Boehringer Ingelheim Animal Health). Heifers were also subcutaneously injected with Draxxin (Zoetis Animal Health), a recombinant Mannheimia haemolytica leukotoxoid vaccine (Nuplura PH, Elanco Animal Health), and a modified-live virus vaccine (Titanium 5, Elanco Animal Health) containing infectious bovine rhinotracheitis (IBR), bovine viral diarrhea (types 1 and 2), bovine respiratory syncytial virus, and parainfluenza 3. Finally, heifers were implanted with Revalor-H (Merck Animal Health).
After processing, cattle were returned to their receiving pen until all cattle had been processed at 48-hous after arrival to the facility. The heifers were weighed individually on days 0, 7, 14, 21, 28 and 35 to calculate average daily gain (ADG). Feed was individually weighed and delivered to each heifer twice daily, with refusals collected and weighed daily to determine dry matter intake (DMI). A fecal egg count reduction test and analysis of blood serum metabolites were also conducted.
Growth performance, mortality, and morbidity data are presented in Table 1. Processing time did not impact heifer body weight (BW) or ADG for the duration of the experiment. Over the overall experiment, (day 0 to 35), DMI decreased linearly (P = 0.027) as rest time increased.
The number of days for heifers to reach a DMI of 2.5% of BW was linearly increased (P = 0.023) as time of rest increased, with heifers processed at 0, 6, 24 or 48 hours requiring 18, 15, 18 and 20 days to reach this parameter, respectively. Similarly, rest time impacted (P = 0.038) the percentage of heifers that reached a targeted DMI of 2.5% of BW by day 14 of the experiment, with 25.0%, 60.0%, 52.6% and 23.5% of cattle reaching this parameter after 0, 6, 24 and 48 hours of rest prior to processing, respectively.
Gain efficiency did not differ (P ≥ 0.70) between rest times. Morbidity did not differ between treatments (P > 0.10), whereas mortality increased linearly (P = 0.026) as the time of rest increased. This increase was due to the loss of two experimental animals in the 48-hour treatment on day two of the study.
These researchers concluded that rest time prior to processing did not impact receiving calf growth performance. Their data did suggest that six hours, or approximately one hour of rest per hour of transport time, was the most beneficial to maximizing DMI during the first 14 days after arrival to the feedlot.
Anthelmintic treatment at processing reduced the parasitic load in all heifers, regardless of their rest time upon arrival. Vaccine titer did not increase after initial processing in heifers processed 24- or 48-hours after arrival, indicating the seroconversion of IBR antibodies during the longer rest period.
References 1 González, L. A., K. S. Schwartzkopf-Genswein, M. Bryan, R. Silasi, and F. Brown. 2012. Factors affecting body weight loss during commercial long haul transport of cattle in North America. J. Anim. Sci. 90:3630-3639. 2 Cernicchiaro, N., B. J. White, D. G. Renter, A. H. Babcock, L. Kelly and R. Slattery. 2012a. Associations between the distance traveled from sale barns to commercial feedlots in the United States and overall performance, risk of respiratory disease, and cumulative mortality in feeder cattle during 1997 to 2009. J. Anim. Sci. 90:1929-1939. 3 Cernicchiaro, N., B. J. White, D. G. Renter, A. H. Babcock, L. Kelly and R. Slattery. 2012b. Effects of body weight loss during transit from sale barns to commercial feedlots on health and performance in feeder cattle cohorts arriving to feedlots from 2000 to 2008. J. Anim. Sci. 90:1940-1947. 4 Van Engen, N. K., and J. F. Coetzee. 2018. Effects of transportation on cattle health and production: a review. Anim. Health Res. Rev. 19:1–13. 5 Duff, G. C. and M. L. Galyean. 2007. BOARD-INVITED REVIEW: Recent advances in management of highly stressed, newly received feedlot cattle. J. Anim. Sci. 85: 823-840. 6 Thomson, D. U., J. Eisenbarth, J. Simroth, D. Frese, T. L. Lee, M. Stephens, and M. Spare. 2015. Beef cattle transportation issues in the United States. In: Forty-Eighth Annual Conference of the American Association of Bovine Practitioners, New Orleans, LA. p 16–22. 7 Dahmer, P. L., C. A. Zumbaugh, M. E. Reeb, N. B. Stafford, Z. T. Buessing, K. G. Odde, J. S. Drouillard, A. J. Tarpoff and C. K. Jones. 2022. Impacts of a post-transport/pre-processing rest period on the growth performance, anthelmintic efficacy, and serum metabolite changes in cattle entering a feed yard. Transl. Anim. Sci. 6. Available at: https://doi.org/10.1093/tas/txac085.
Hicks is a beef nutritionist and Extension livestock specialist with Oklahoma State University.
