1 Adapting Angus Cattle to Subtropical Climates John Arthington University of / IFAS Range Cattle Research and Education Center, Ona Overview Typical commercial cow/calf herds are comprised of Brahman x British crossbreds. Significant percentage of herd sires are purchased outside. Black Angus genetics are often imported from temperate regions. Overview Initial Research There is considerable discussion among producers relative to the merits of bull acclimation. Select from tropical/subtropical herds? Yearlings imported and reared year before first used as a 2 year old. Is it even a significant consideration in a winter breeding season? 2 embryos were derived from local (adapted) or outside (non adapted) sources (n = 20 total). Embryos were transferred into Brahman x British crossbred cows over three consecutive years. From these transfers, a total of 8 live calves were weaned. Heifers and bulls evaluated through sexual maturity. Bulls evaluated as sires on Braford cowherd. Riley et al. 20. J. Anim. Sci. 89:226 Initial Research Initial Research Item Local () Outside () SEM P = Average low, o C Average high, o C Range, o C Hair coat score Item Bulls Heifers SEM P = Hair coat score Item Local () Outside () SEM P = n = Birth weight, lb Weaning weight, lb d adjusted, lb Weight/d of age, lb Hip height, cm < 0.0 Age at conception, d
2 Initial Research - Bulls Overview ( years later) Weaning Wt., lb P = 0. In 20 we noticed that many of the sourced cows were already culled from the herd or placed into groups designated for culling. Most of the sourced cows remained in the herd. WHY? Riley et al. 20. J. Anim. Sci. 89:226 Cow Age n = Study Design Study Design Study was conducted over three consecutive years using cow/calf pairs. Local Source; Adapted Herd Outside Source; Modern Seedstock Herd () Calves were fall borne over a 90 d period. Evaluations were conducted in March, April, May, and June of each year. Dependent variables included; Cow and calf BW Cow BCS Cow hair coat score Cow milk production (WSW; March only) Data analyzed using the MIXED procedure of SAS with source in the model and animal(source x year) as random variable. Individual animal was the experimental unit. Study Design Cow BW and BCS Cow hair coat score based on scoring criteria established by Dr. Joe Cassady, North Carolina State University, as follows; Hair Shedding Score Definition Full winter coat Coat exhibits initial shedding 3 Coat is halfway shed 2 Coat is mostly shed Slick, short summer coat Item SEM P = n = BW (lb, March) BW (lb, June) 97, BCS (March) < 0.00 BCS (June) BCS; to 9 scale 2
3 Calf BW, lb Hair Coat Shedding Item SEM P = Calf (March) Calf (June) ADG Adjusted for calf sex Hair coat score ( to scale) 3 2 P = P = March April May June Hair Coat Shedding 2-h Adjusted WSW Milk Production Estimates Hair coat score ( to scale) 3 2 P = 0.03 P = 0.2 P = Milk production, lb/d % Greater (P < 0.00) milk production 0 Average Score Score Change Maximum Score Summary Calves from non adapted, outside source Angus dams had greater pre weaning BW gain. Compared to local source, adapted Angus dams, outside source Angus dams; Less BCS Slower spring hair coat shedding Greater milk production 3
4 Where did they come from? The is a distinct breed developed at the UF/IFAS Range Cattle Research and Education Center. A coloration anomaly that is not fully understood. Originally derived from a long term cattle breeding project lead by Professor F.M. Peacock (Ona) involving the crossbreeding of Brahman, black Angus, and Charolais. Where did they come from? In the early 990 s this cowherd was bred to Simbrah bulls. In 999, we began to breed to black Angus and Brangus. In 2002, we began to notice a small number of these cows giving birth to white haired calves with dark skin. Since this time, we have focused on increasing the numbers. Where did they come from? Foundation White Angus Cow (n = 22) Purebred Black Angus Sire (AI) Cows (n = 0) Bulls (n = 8) Originally, we focused on producing White Angus calves that were genetically 7/8 black Angus. This has not worked! Results in: st Generation > 7% Black Angus Genetics (0% proportion) Results in: > 7 % Black Angus Genetics (90+ % proportion) To date, only one cow has produced a 7/8 black Angus calf. She has 3 daughters in the herd. Today, we are focusing on breeding white cows to white bulls each are ¾ black Angus. 7/8 black Angus ET daughter of the ABS sire Mandate Two full siblings born from the same flushing that were black. Increased genetic diversity will come from ET of the Foundation White Cows 20 cow X 6 flushes/yr X viable embryos/flush X 0% result in X 0% live calves born = 96 heifer calves (year ) Currently; there are approx. 0 Ona White Angus Cows and 8 Bulls in the herd 0 cow X 6 flushes/yr X viable embryos/flush =,200 embryos (year ) All embryos and/or live calves could be available for Worldwide marketing. After years and 2, embryo and calf production limits are greatly increased depending on demand. What are the advantages? In collaboration with researchers from Cornell University we determined that the have > 80% sweating rates when compared to black Angus cattle reared in the same environment (ASABE (6):267). This adaptive response results in cooler body temperatures during periods of high heat load. Collectively, the cattle spend less time seeking shade and more time grazing than black Angus cattle. Vaginal temperature, o C White Angus Black Angus Hour of day Figure 2. Influence of hair coat color on vaginal temperature of pre-weaned Angus heifer calves.
5 Forage Intake and Grazing Characteristics Forage Intake and Grazing Characteristics Hair Coat Color Item White Black SEM P = Forage DMI, % BW Time spent in shade < 0.0 Voluntary intake of ground grass hay in a fully shaded individual feeding facility. 2 Percent of time spent in shaded area over a 2 h summer day (07:00 to 9:00) Why are we selling the herd? The genetic diversity of the is limited. This can be enhanced/improved by an aggressive embryo transfer program focused at mating our Foundation cows (0% black Angus) with multiple black Angus sires. But, this is expensive.... In addition, it is a natural expectation for the University to develop technologies and transfer them to the private sector for commercialization. As a breed, the has the potential to provide significant value to the beef cattle production systems in warm climates. Foundation Heifer Foundation Cow with Calf Heifer (2 years of age)
6 Heifer (7/8 black Angus) Bull (3/ black Angus) Bull (returning from test) Heifers (weaned yearlings) Bulls (Yearlings) Heifer (2-year old) 6
7 Sale Heifer (unweaned; 6 mo) Sale Date: January 2, 206 at 0 AM EST Cattle will be sold as a single group. No cattle, embryos or semen will be retained. Minimum reserve; $700,000. Auction will be available on site or via internet. Buyers must be registered with Producers Cattle Auction before the sale: www. Producerscattleauctions.com Contact: Todd Clemons, Okeechobee Livestock Mkt. Sale Sale At buyers discretion, the cattle can remain at the UF/IFAS Range Cattle Research and Education Center through a negotiated management/research contract. Prior to the sale, the cattle may be viewed on; October 22 November 20 December 8 Information updates are provided as they become available at ona.ifas.ufl.edu/ Audy Spell Advanced Reproductive Associates AND Todd Clemons Okeechobee Livestock Mkt. Thank you for your attention John Arthington University of / IFAS Range Cattle Research and Education Center, Ona 7