Grazing Supplementation Research Articles

Relative value of field pea supplementation compared with distillers grains for growing cattle grazing crested wheatgrass

The objective was to determine a salvage value for field peas (FP) relative to dried distillers grains plus solubles (DDGS) and establish a pricing system for FP as a supplement for growing cattle in regions where FP are grown and DDGS has limited availability. In a 2-yr study, 114 heifers each year (294 ± 34.6 kg, yr 1; 306 ± 16.3 kg, yr 2) grazed crested wheatgrass pastures (n = 12). Treatments were arranged in a 2 × 2 factorial arrangement with the main factors being supplement type (FP or DDGS) and level (0.4 or 0.8% of BW). Pasture was the experimental unit, and cattle were blocked by BW. The experimental design was a randomized complete block design. There were no interactions between supplement type and level ( P > 0.22). Level of supplement was not different ( P > 0.15) for ADG (1.00 vs. 1.06 kg/d) or BW (416 vs. 421 kg) for 0.4 versus 0.8% BW, respectively. Heifers supplemented DDGS had greater gain ( P = 0.02) than those supplemented FP (1.09 vs. 0.98 kg/d, respectively). Final BW was greater for heifers supplemented with DDGS (425 kg) compared with FP (411 kg; P = 0.04). Field pea–supplemented heifers had 10% lower ADG and 9% greater cost of gain compared with DDGS-supplemented heifers. Field peas are an acceptable grazing supplement but result in ADG 10% less than DDGS, with a supplement cost of gain 9% greater than DDGS, warranting approximately 10% price reduction before transportation.

Techniques to Estimate Colostrum Quality and the Effects of Cow Age and Pre-Partum Supplement Intake Levels on Colostrum Quality and Serum IgG Levels

This study evaluated cow age and supplement intake level during gestation on the quality of colostrum at calving, cow serum immunoglobulin G (IgG) levels at parturition, and serum IgG levels of the calf 3-days post-partum using two refractometer methods. Forty-five multiparous Angus cows were selected from a contemporary group of 300 cows that were winter grazing northern mixed grass prairie rangelands with free choice protein supplement. Specifically, 15 first service bred cows were selected for each of the following winter grazing supplement intake treatment groups: 1) low supplement intake (> -0.75 SD); 2) average supplement intake (± 0.50 SD); 3) high supplement intake (> +0.75 SD). Supplement intakes were measured using a SmartFeed Pro self-feeder system with 8 feeding units. Measurements were obtained from day 164 to 215 of gestation. Cows were further divided by age comparing young (4, 5, and 6 yr) to old (7, 8 and 9 yr). The results of this study suggest that cow age did not interact with supplement intake for colostrum or blood serum measurements (P ≥ 0.29). In addition, cow age and supplement intake did not influence colostrum Brix %, calf serum total protein, or cow serum total protein taken at birth (P ≥ 0.14). The optical refractometer was found to be a good alternative to the more expensive digital refractometer (P < 0.01; R = .96). In summary, cow age and supplement intake levels of mature cows during the mid to late stages of gestation did not influence colostrum quality at birth.

Viabilidade econômico-financeira de sistemas de produção de cordeiros não desmamados em pastagem com suplementação em cocho ou pasto privativo

Objetivou-se analisar os custos e a rentabilidade de sistemas de produção de ovinos em pastagem sob três estratégias de suplementação de cordeiros lactentes: (1) creep grazing de trevo branco; (2) creep feeding; e (3) sem suplementação. Utilizaram-se dois métodos de análise financeira: análise anual (de curto prazo) e de fluxo de caixa (de longo prazo). Os custos foram segmentados em variáveis, fixos, operacionais e totais. O fator de produção que exerceu maior influência no custo variável da produção foi a alimentação, e no custo total foi o custo de oportunidade do capital imobilizado. O sistema com creep grazing não apresentou resultados econômico-financeiros superiores aos com creep feeding.

Effects of starch- vs. fiber-based energy supplements during winter grazing on partitioning of fat among depots and adipose tissue gene expression in growing cattle and final carcass characteristics

Fifty-five normal-weaned Angus steers (268 ± 22 kg; 265 ± 16 d of age) were used to evaluate the effects of starch- vs. fiber-based energy supplements for stocker cattle grazing low-quality dormant native range on growth performance, body composition, and adipose tissue development of different fat depots. Steers were randomly allotted to 4 treatments: 1.02 kg·steer(-1)·d(-1) of a 40% CP cottonseed meal-based supplement (CON), corn/soybean meal-based supplement fed at 1% of BW (CORN), soybean hull/soybean meal-based supplement fed at 1% of BW (SBH), or dried distillers grains with solubles fed at 1% of BW (DDGS). All supplements were individually fed 5 d/wk during the 121-d winter grazing phase. After winter grazing, 3 steers per treatment were harvested to determine body composition and carcass characteristics, and collect subcutaneous (SC) and perirenal (PR) adipose tissue samples. The remaining steers grazed cool-season grass pastures for 74 d without supplementation before finishing. Steers were fed a common finishing diet for 113 d before harvest, at which time carcass characteristics were collected at a commercial abattoir. Energy supplementation increased (P < 0.01) winter grazing ADG compared with CON steers, and CORN steers had greater (P < 0.01) ADG than SBH and DDGS steers. Energy supplementation increased (P < 0.04) mesenteric/omental fat mass but did not influence (P > 0.13) 12th rib fat thickness or marbling score at intermediate harvest compared with CON steers. The mRNA expression of genes involved in lipogenesis and markers of adipogenesis were greater (P < 0.05) in PR adipose tissue of energy-supplemented steers compared with CON steers but not in SC adipose tissue. Fiber-supplemented steers had greater (P < 0.01) mRNA expression of fatty acid synthase and fatty acid binding protein 4 compared with CORN steers in PR adipose tissue but not SC adipose tissue. At final harvest, energy-supplemented steers had greater (P < 0.05) KPH and yield grade than CON steers, but no differences (P = 0.75) in marbling score were observed. Neither energy supplementation nor type of energy supplement influenced intramuscular fat deposition in stocker cattle grazing dormant native range. These data suggest that the total energy intake and stage of animal maturity during grazing supplementation were not great enough to influence marbling deposition.

Effect of Energy Supplementation of Stocker Cattle Grazing Smooth Bromegrass Pastures on Grazing and Subsequent Finishing Performance and Carcass Traits

Grazing and subsequent finishing performance of 117 Angus stocker calves (Bos taurus; BW = 235.5 ± 1.22 kg) supplemented with 0, 0.82, or 1.64 kg/d of grain sorghum (Sorghum bicolor) on a DM basis while grazing smooth bromegrass (Bromus inermis) pastures in 2002, 2003, and 2004 were evaluated. Cattle continuously grazed pastures at a stocking rate of 2 steers/ha from mid-April to early November of each year and were then finished for slaughter and collection of carcass data. Supplementation with 0.82 or 1.64 kg/d of grain sorghum resulted in 11.2% greater (P 0.05) on forage mass, finishing ADG, or DMI during the finishing phase. Cattle supplemented during the grazing phase maintained their weight advantage through the finishing phase, were heavier (P < 0.05) at slaughter, yielded heavier (P < 0.05) carcasses, and had greater (P < 0.05) overall ADG than those that received no supplement. Cattle supplemented with 0.82 kg/d of grain sorghum required less (P < 0.05) feed per unit of gain during the finishing phase than those that were previously supplemented with 1.64 kg/d. Supplementation with 1.64 kg/d of grain sorghum during the grazing phase resulted in a greater (P < 0.05) marbling score than feeding no grazing supplement. Overall ADG from the beginning of the grazing phase through the end of the finishing phase was greater (P < 0.05) for cattle that were supplemented with grain sorghum while grazing.

Contribution of Erythrina protein banks and rejected bananas for improving cattle production in the humid tropics

In view of the low pasture productivity in the Central American humid tropics where cattle rearing is a major land-use activity, it is important to examine the potential of alternate feed sources for ruminant feeding. Erythrina berteroana Uban, locally known as poro, and green banana (Musa AAA) fruits have been identified as two such potential sources. The effects of feeding poro as a grazing supplement and diet supplementation with green banana fruits on cattle productivity were evaluated in a long-term trial in Costa Rica. Daily liveweight (LW) gains were measured and samples of all feed material were analyzed for crude protein and in vitro dry matter (DM) digestibility. Pasture availability was high, averaging 0.17 t DM ha day−1 over the grazing period. The main grass species were Paspalum fasciculatium Poiret, Axonopus compressus Swartz and to a lesser extent African star grass (Cynodon nlemfluensis Vanderyst). DM yields of poro declined significantly with time (> 50%) when it was managed with a two-month resting period but remained higher when subsequently managed with a three-month resting period. Average daily LW gain of animals was 21% to 26% higher with two hours daily browsing of poro than for animals only grazing pasture. Highest liveweight gain was achieved when diets were supplemented with banana and there was no additional benefit when poro was fed in addition to banana. This suggests that fodder banks of poro or supplements with green banana can improve cattle nutrition in the humid tropics.

Effects of supplemental ground grain sorghum during grazing of endophyte-infected tall fescue on grazing and subsequent feedlot performance of steers (1991)

Sixty-three crossbred steers (740 lb BW) were used to evaluate the effects of energy supplementation during grazing of endoplyteinfected tall fescue and on their subsequent feedlot performance. Grazing ADG was .53 lb/d for control (no supplementation) vs. .81 and 1.21 lb/d with .25% and .5% of BW as ground sorghum (GS), respectively. Grazing supplementation did not affect (P>.10) feedlot performance. Steers receiving .25% GS were 2.3% and 6.2% more efficient (P<.07) during the feedlot phase than 0% and .5% GS steers, respectively. The .5% GS steers were 3.8% less efficient (P<.07) during the feedlot phase than the 0% GS steers. Steers receiving grazing supplementation had increased (P<.07) adjusted backfat measurements and less desirable (P<.02) yield grades than non-supplemental controls. Supplementing steers grazing endophyte-infected fescue at .25% of BW with ground grain sorghum improved feedlot feed conversion compared to no supplementation and supplementing at .5% BW.

The effect of age at which spring-born calves are introduced to pasture

SummarySpring-born Friesian heifer calves were turned out to grass at either 3 or 4 months of age. In the summer of 1976 the experiment had 20 calves per treatment and in 1977 there were 22 calves per treatment. The calves remained outside for both day and night. They were the leaders in a leader–follower rotational grazing system based on nine paddocks. The followers were yearling heifers and sheep. Each calf was offered a daily grazing supplement of 1·8 kg concentrates. Housing was in mid-September.There were no management problems and summer growth rates were within the range 0·55–0·74 kg/day. Calves turned out at 3 months of age grew slightly better than calves turned out at 4 months. This difference was not statistically significant, but it does suggest there is no harm in turning calves out at an early age. From a practical viewpoint the result indicates that all spring-born calves could be turned out in one batch in early summer.