K. Larson

Effect of winter feeding system on beef cow performance, reproductive efficiency, and system cost1

A 3-yr study was conducted to evaluate the effects of winter feeding systems on beef cow performance, reproductive efficiency, and system cost. Winter feeding systems were (i) swath grazing (SG) windrowed whole-plant barley [TDN = 62.4, CP = 13.4 (% DM)] in field paddocks; (ii) bale grazing (BG) barley hay round bales [TDN = 66.6, CP = 13.1 (% DM)] in field paddocks; (iii) straw-chaff grazing (STCH) barley crop residue piles [TDN = 46.8, CP = 9.8 (% DM)] in field; and (iv) drylot feeding (DL) barley hay round bales [TDN = 67.9, CP = 13.0 (% DM)] in bale feeders in pens. The study was conducted over 3 production cycles with spring-calving beef cows [yr 1 (78 d), n = 180, BW = 630.5 ± 3.9 kg; yr 2 (21 d), n = 180, BW = 598.6 ± 7.7 kg; yr 3 (36 d), n = 120, BW = 644.0 ± 5.0 kg]. Cows were allocated swaths, bales, and crop residue piles on a 3-d basis to manage DMI and feed waste. Dry matter and TDN intakes were 17 and 23% lower (P 0.05) on cow reproductive performance. In yr 1, in the first 21 d, cows maintained BW and BCS with DL compared with SG, BG, and STCH cows. However, SG, BG, and STCH cows gained BW linearly (r = 0.58, P = 0.09) from d 22 to 76 of the feeding trial. Cows in drylot pens fed round bale hay gained more BW than did cows in field paddocks grazing either round bales (P < 0.05; yr 3) or swaths (P < 0.05; yr 2, yr 3). In yr 1 after 78 d, SG cows had lower BW and BCS (P < 0.05) than did DL cows; however, cows in all systems gained BW in yr 2 and 3. Averaged over 3 yr, winter feeding system costs were 8 and 29% lower for BG and SG, respectively, compared with the DL system. This research indicates that bale grazing or swath grazing systems can be effective alternatives to reduce winter feeding costs.

Comparison of alternative backgrounding systems on beef calf performance, feedlot finishing performance, carcass traits, and system cost of gain1

A 3-yr experiment was conducted to evaluate the effects of swath grazing forage barley (Hordeum vulgare; cv. Ranger) or foxtail millet (Setaria italica; cv. Golden German) compared with grass-legume hay fed in drylot pens on

C omparison of grazing oat and pea crop residue versus feeding grass-legume hay on beef- cow performance, reproductive efficiency, and system cost 1

Spring-calving nonlactating pregnant Angus (Bos taurus) cows (yr 1, n = 90, BW = 637.6 ± 5.8 kg; yr 2, n = 78, BW = 671.2 ± 8.1 kg; yr 3, n = 68, BW = 669.4 ± 6.6 kg) were managed in 1 of 3 replicated (n = 3) wintering systems: (i) grazing oat residue [OATG; TDN = 58.6, CP = 6.7 (% DM)] piles in field paddocks; (ii) grazing pea residue [PEAG; TDN = 50.9, CP = 11.1 (% DM)] piles in field paddocks; and (iii) drylot (DLPF) pen feeding grass–legume round bales [TDN = 54.5, CP = 10.4 (% DM)] in bale feeders. The study was conducted over 3 production cycles, and cows were allocated crop residue and bales on a 3-d basis to manage utilization and feed waste. Forage utilization was less (P < 0.05) in PEAG (33.4 ± 4.3%) and OATG (44.9 ± 5.9%) systems than in the DLPF (90.0 ± 1.63%) wintering system. Dry matter intake of cows varied (P < 0.05) among systems; cows consuming PEAG or OATG had less (P < 0.01) DMI compared with DLPF cows. Nutrient (CP, TDN) intake was greatest (P < 0.05) for DLPF cows and least for cows in the PEAG system. Cows grazing PEAG residue lost BW (11 kg) from d 1 to 20; however, BW change during the entire trial period (63 d) was positive (4 kg) for PEAG cows but less (P = 0.01) than OATG (27 kg) or DLPF (66 kg) cows. Calf birth weight was least (P = 0.03) for OATG cows than DLPF cows, 39 vs. 42 kg, respectively. On average, total costs for the OATG and PEAG winter feeding strategies were

Effect of development system on growth and reproductive performance of beef heifers

0.77 and

Effect of calving period on beef cow longevity and lifetime productivity in western Canada

0.59 cow/d less than the DLPF (

Effects of supplementing spring-calving beef cows grazing barley crop residue with canola meal and wheat-based dry distillers grains with solubles on performance, reproductive efficiency, and system cost

2.13 cow/d) system, respectively. Grazing crop residue for part of the winter feeding program of a cow has cost advantages over pen-feeding hay; however, environmental conditions (snowfall, temperature) dictate forage accessibility. Therefore, producers with access to crop residues should consider using this feed in a chaff-straw based ration along with adequate supplementation to ensure the nutritional needs of the cow are being met.

Swath Grazing CDC SO-1 Oat and Red Proso Millet with Beef Cows

Reproductive performance was evaluated in beef heifers born over a 2-yr period to determine the effects of target breeding weight (TBW) and development system (SYS) on growth and subsequent reproductive efficiency. Spring-born Angus heifers (253 ± 0.7 kg) were randomly allocated over 2 consecutive yr (yr 1, n = 80; yr 2, n = 96) to be developed to either 55% (350 kg) of mature BW (moderate gain, MG) or 62% (395 kg) of mature BW (high gain, HG). Each MG and HG group was further assigned to 1 of 2 replicated systems: (1) bale graze bromegrass-alfalfa round bales in field paddocks (BG) or (2) fed bromegrass-alfalfa round bales in drylot pens (DL). Heifers were fed a diet of bromegrass-alfalfa hay (56.9% TDN; 9.8% CP) and barley grain supplement (85.1% TDN; 12.3% CP). After the 202-d development period, heifers were exposed to bulls for a 63-d breeding season. Target BW × SYS interactions were not detected for any measured parameters. During the winter development period, MG heifers had lower (P = 0.01) ADG than HG heifers and MG heifers had lighter (P = 0.01) BW at breeding. The proportion of heifers attaining puberty by 14.5 mo of age was less (P = 0.05) in MG (20 ± 4%) than HG heifers (52 ± 3%). From the end of the 202-d development period to pregnancy diagnosis, ADG was greater (P = 0.04) in MG heifers than HG heifers (0.83 vs. 0.71 kg/d). First-calf pregnancy rates were 86 and 88% for MG and HG heifers, respectively (P = 0.41). Second- and third-calf pregnancy rates of cows, developed in either a MG or HG system as heifers, were not different (P = 0.74; 94.7 vs. 95.9% and 93.8 vs. 93.9%, respectively). Economic analysis revealed a

Effect of perennial forage system on forage characteristics, soil nutrients, cow performance, and system economics

58 reduced development cost for heifers developed to 55% compared with 62% of mature BW without a loss in reproductive performance.

EFFECT OF PERENNIAL FORAGE SYSTEM ON FORAGE CHARACTERISTICS, COW PERFORMANCE AND SYSTEM ECONOMICS

© The Author(s) 2018. Published by Oxford University Press on behalf of the American Society of Animal Science. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited. For commercial re-use, please contact journals.permissions@oup.com. Transl. Anim. Sci. 2018.2:S61–S65 doi: 10.1093/tas/txy020