D.C. Blouin

Effects of year-round stocking rates and stocking methods on performance of cow-calf pairs grazing dallisgrass-common bermudagrass pastures overseeded with annual ryegrass1

Beef producers throughout the United States frequently are restricted to a fixed land area that varies considerably in carrying capacity throughout the year. Much of the research that has focused on stocking rate and methods (continuous, rotational) has failed to recognize the inability of most producers to use a variable stocking rate. Two sets of 4 adjacent pastures, each containing a mixed warm-season, perennial grass sod [common bermudagrass, Cynodon dactylon (L.) Pers.; dallisgrass, Paspalum dilatatum Poir.] were overseeded to ‘Marshall’ annual ryegrass (Lolium multiflorum) in the autumn of 3 consecutive years. Within each set of 4 pastures, one of the following grazing treatments was randomly assigned each pasture: continuous stocked at a low, medium, or high stocking rate (CL, CM, and CH) and rotational stocked (8 paddocks) at a high stocking rate (RH). Low, medium, and high stocking rates were 1.25, 2, and 2.75 cows/ha, respectively. Brangus cows and their suckling calves were stocked on treatment pastures in February 1999. Available forage mass tended to be greater (P = 0.10) for CL than CM in the late spring and was greater (P < 0.05) for CL than CM in the summer grazing season. Differences in forage nutritive value were largely associated with the stocking method comparison, favoring CH in the early spring (percent CP, percent in vitro true digestibility, and percent ADF; P < 0.01) and summer (percent CP and percent ADF; P < 0.01) grazing seasons. Cow-calf productivity, as measured by kilograms of calf wean weight per hectare, increased (P < 0.01) in response to increases in stocking rate, but was similar between the continuous and rotational stocking methods at the high stocking rate.

Effects of year-round stocking rate and stocking method systems on performance of cow-calf pairs in the gulf coast region of the United States1

ABSTRACT The present research is the second phase (2xa0yr) of a multiyear cow-calf project examining the effect of stocking method, i.e., continuous and rotational, and fixed stocking rate on beef-cattle production. Two sets of 4 adjacent pastures, each containing a mixed warm-season, perennial grass sod [common bermudagrass, Cynodon dactylon (L.) Pers.; dallisgrass, Paspalum dilatatum Poir.], were overseeded to ‘Marshall’ annual ryegrass (Lolium multiflorum) in the autumn of 2 consecutive years. Within each set of 4 pastures, 1 of the following grazing treatments was randomly assigned each pasture: rotationally stocked (8 paddocks) at a low, medium, or high stocking rate (RL, RM, and RH) and continuously stocked at a moderate stocking rate (CM). Low, medium, and high stocking rates were 1.25, 2, and 2.75 cows/ha. Brangus cow-calf pairs were stocked on treatment pastures in March 2004. Mean cow BW was greater for RL compared with RM (P 0.20) for the RM versus RH (522xa0kg) and the RM versus CM (530xa0kg) stocking-treatment comparisons. Calf-adjusted 205-d BW was similar for all treatment contrasts. Pasture weaning BW differed between the RL versus RM (P

Influence of Angus and Belgian Blue bulls mated to Hereford × Brahman cows on growth, carcass traits, and longissimus steak shear force

Steers and heifers were generated from Angus (A) and Belgian Blue (BB) sires mated to Brahman x Hereford (B x H) F(1) cows to characterize their growth, carcass traits, and LM shear force. A total of 120 B x H cows purchased from 2 herds and 35 bulls (14 A and 21 BB) produced calves during the 5-yr project. After the stocker phase, a representative sample of A- and BB-sired heifers and steers were transported to the Iberia Research Station to be fed a high-concentrate diet. The remaining cattle were transported to a commercial feedlot facility. Each pen of cattle from the commercial feedlot was slaughtered when it was estimated that heifers and steers had 10 mm of fat or greater. The BB-sired calves were heavier at birth (P < 0.01) than the A-sired calves. During the feedlot phase, the A-sired calves gained more BW (P < 0.05) than the BB-sired calves. The BB-sired calves had heavier (P < 0.01) carcass weights than the A-sired calves. This was due to a combination of a heavier final BW and greater dressing percent. Because of their greater muscling and reduced (P < 0.01) fat, carcasses from BB-sired calves had greater yield (P < 0.01) compared with carcasses from A-sired calves. Carcasses from A-sired calves had a greater (P < 0.01) marbling score and greater (P < 0.01) USDA quality grade than carcasses from BB-sired calves. Tenderness, as measured by shear force of the steaks aged for 7 d, was similar for A- and BB-sired calves. However, steaks aged for 14 d from the A-sired calves had a reduced shear force (P < 0.01) compared with steaks from the BB-sired calves. Steer calves were heavier (P < 0.01) at birth and weaning, and had more total BW gain in the feedlot, which resulted in a heavier final BW and HCW compared with the heifers. Steer carcasses also had greater marbling scores and quality grades, whereas the heifer carcasses had larger LM area per 100 kg of carcass weight. In conclusion, the BB-sired calves had heavier carcass weights and greater cutability, whereas the A-sired calves had a greater degree of marbling and greater quality grade, and steaks from carcasses of A-sired calves were more tender as measured by shear force at 14 d.

Effects of year-round stocking methods and stocking rates on seasonal forage response and cow-calf weight gain in the gulf coast region of the United States1

The present research is the second phase (2 yr) of a multiyear cow-calf study employing fixed stocking rates and examining the effect of stocking method, i.e., continuous and rotational, and stocking rate on beef cattle production. Two sets of 4 adjacent pastures, each containing a mixed warm-season, perennial grass sod [common bermudagrass, Cynodon dactylon (L.) Pers.; dallisgrass, Paspalum dilatatum Poir.], were overseeded to ‘Marshall’ annual ryegrass (Lolium multiflorum) in the autumn of 2 consecutive years. Within each set of 4 pastures, one of the following grazing treatments was randomly assigned each pasture: rotationally stocked (8 paddocks) at a low, medium, or high stocking rate and continuously stocked at a moderate stocking rate. Low, medium, and high stocking rates were 1.25, 2, and 2.75 cows/ha. Brangus cows and their suckling calves were stocked on treatment pastures in March 2004. Stocking treatment affected prebreeding cow BW (P < 0.01) and tended to affect precalving (P = 0.13), postbreeding (P = 0.07), weaning (P = 0.11), and subsequent precalving cow BW (P = 0.08). Stocking-method treatments were similar in forage allowance in the early- and late-spring periods (P = 0.67 and P = 0.65, respectively), but in the summer period, rotationally stocking at a medium stocking rate was greater (P < 0.01) than continuously stocking at a moderate stocking rate. There was a consistent trend across seasons for the percent CP in the simulated bite sample DM to be greater (P < 0.1) for the continuously stocking at a moderate stocking rate compared with the rotationally stocking at a medium stocking rate stocking methods. Based upon cow BW outcomes in this research, stocking rate is the most important consideration in design of a grazing program.

Bale Location Effects on Nutritive Value and Fermentation Characteristics of Annual Ryegrass Bale Stored in In-line Wrapping Silage

In southeastern regions of the US, herbage systems are primarily based on grazing or hay feeding with low nutritive value warm-season perennial grasses. Nutritious herbage such as annual ryegrass (Lolium multiflorum Lam.) may be more suitable for preserving as baleage for winter feeding even with more intensive production inputs. Emerging in-line wrapped baleage storage systems featuring rapid wrapping and low polyethylene film requirements need to be tested for consistency of storing nutritive value of a range of annual ryegrass herbage. A ryegrass storage trial was conducted with 24-h wilted ‘Marshall’ annual ryegrass harvested at booting, heading and anthesis stages using three replicated in-line wrapped tubes containing ten round bales per tube. After a six-month storage period, nutritive value changes and fermentation end products differed significantly by harvest stage but not by bale location. Although wilted annual ryegrass exhibited a restricted fermentation across harvest stages characterized by high pH and low fermentation end product concentrations, butyric acid concentrations were less than 1 g/kg dry matter, and lactic acid was the major organic acid in the bales. Mold coverage and bale aroma did not differ substantially with harvest stage or bale location. Booting and heading stage-harvested ryegrass baleage were superior in nutritive value to anthesis stage-harvested herbage. Based on the investigated nutritive value and fermentation characteristics, individual bale location within in-line tubes did not significantly affect preservation quality of ryegrass round bale silages.

Effects of year-round stocking rate and stocking method systems on cow-calf production in the gulf coast region of the United States: Costs, returns, and labor considerations1

ABSTRACT The present research examines the effect of stocking method, i.e., continuous and rotational, and set (fixed) stocking rate on labor requirements, costs, and profits in cow-calf beef production. Two replicates of 4 adjacent pastures each, containing a mixed warm-season, perennial grass sod [common bermudagrass, Cynodon dactylon (L.) Pers.; dallisgrass, Paspalum dilatatum Poir.], were overseeded to ‘Marshall’ annual ryegrass [Lolium multiflorum (Lam.)] in the autumn of 2 consecutive years. Within each replicate of 4 pastures, one of the following grazing treatments was randomly assigned each pasture: rotationally stocked (8 paddocks) at a low, medium, or high stocking rate (RL, RM, and RH) and continuously stocked at a moderate stocking rate (CM). Labor activities, expenditures, sales, and equipment usages were recorded throughout the study. On a per-cow basis, total labor usage declined (P 0.90) and would not justify the additional labor associated with rotational grazing management.

Effects of Fish Meal and Sodium Bentonite on Performance, and Ruminal and Blood Characteristics of Kids Fed Concentrate or Forage Diets,

Twenty-four wether and 24 doe crossbred kids were used to evaluate the effect of fish meal (FM) and sodium bentonite (NaB) on growth, and ruminal and blood metabolites. Six treatments were: four isonitrogenous (13.5% CP) diets (0% FM and 0% NaB; 0% FM and 0.75% NaB; 3% FM and 0% NaB; or 3% FM and 0.75% NaB) fed to confined kids, and the 0% FM and 0% NaB or 3% FM and 0% NaB diets fed to grazing kids as supplement. Diets were based on corn, soybean meal, and cottonseed hulls. Data were analyzed as two independent 2 × 2 factorial arrangements. The first analysis compared the four diets fed in confinement. The second analysis compared 0 or 3% FM supplemented diets fed in confinement to the same diets fed as supplements to grazing kids. Grazing kids were allowed 8 h daily grazing time on pasture. After grazing, kids were penned individually and allowed access to their respective supplements for 1 h. A FM × NaB interaction (P<0.02) occurred for average daily gain (ADG) where FM improved ADG in the absence of NaB but not in the presence of NaB. There were similar trends noted for DMI and gain per feed (g/kg DMI). Growth rates of confined and grazed kids were similar and both were improved (P<0.01) by including FM in the supplement. Ruminal pH was increased and total VFA decreased by feeding FM to confined kids (P<0.01). Kids that were supplemented after grazing had higher ruminal pH, acetate, isobutyrate, butyrate, and isovalerate and lower propionate levels than kids in confinement. Dietary FM had no effect on blood metabolites of confined or grazed kids. This research suggests that replacing a portion of dietary soybean meal protein with fish meal protein in the absence of NaB improves the growth rate of kids. Grazing kids that are properly supplemented gain as fast on 40% less feed as kids fed complete diets in confinement.

P re- and postweaning calf performances in crossbred cattle from Hereford, Braford, and Bonsmara sires and Angus and Brangus dams 1

Growth traits were evaluated on 560 calves (288 male and 272 female calves) to determine the source and extent of tropical adaptation affecting calf preweaning and postweaning growth performances. Calves with Brangus dams were sired by Braford (BFBN; n = 115; 38% Brahman), Hereford (HEBN; n = 92; 19% Brahman), and Bonsmara (BOBN; n = 139; 19% Brahman and 31% Africander) sires. Calves with Angus (AN) dams were sired by Hereford (HEAN; n = 95) and Bonsmara (BOAN, n = 119; 31% Africander) sires. Growth performances of BFBN and HEBN calves were similar (P > 0.15) for an array of growth traits. However, BFBN and HEBN either tended to (P < 0.10) or had (P < 0.05) greater adjusted birth BW, postweaning ADG, and adjusted 452-d BW when compared with BOBN. Calves with AN dams and Bonsmara sires had greater preweaning ADG (P < 0.05), adjusted 205-d BW (P < 0.01), and adjusted 452-d BW (P < 0.01) than HEAN calves. Among calves with Brangus dams, extent (BFBN vs. HEBN) of tropical adaptation was not important in terms of growth, but source (BFBN vs. BOBN and HEBN vs. BOBN) of tropical adaptation did not favor those calves with Africander breeding. However, for calves with AN dams, the use of Bonsmara sires (BOAN) imparted a growth advantage relative to the HE sires (HEAN). It is important that tropical adaptation, in terms of Brahman and Africander breeding, be imparted to the calf directly but more importantly, that Brahman breeding is imparted maternally.

Effects of temperament on growth and reproductive performance in heifers12

ABSTRACT The present study evaluated the effect of temperament on heifer BW, postweaning gain, and pregnancy status. Temperament was evaluated on 259 Angus-sired and 173 Brahman-influenced heifers. Temperament was assessed on heifers at weaning (FALL) and when they were yearlings (SPR) by chute score (CS), exit velocity (EV), and a combination of CS and EV (COMB). Chute scores were categorized into low (CS 1 and 2), moderate (CS 3), and high (CS 4 and 5). Based upon the mean and SD of each, EV was categorized into 3 levels of slow, moderate, and fast, and COMB score was categorized into 3 levels of low, moderate, and high. The FALL assessment of EV (slow, moderate, and fast), affected (P

Feedlot performance, carcass merit, and meat tenderness in crossbred cattle from Hereford, Braford, and Bonsmara sires and Angus and Brangus dams

ABSTRACT The objective of this research was to evaluate the source and extent of tropical adaptation affecting feedlot and carcass traits. Calves of Brangus (BN) dams were sired by Braford (BFBN; nxa0=xa063; 38% Brahman), Hereford (HEBN; nxa0=xa038; 19% Brahman), and Bonsmara (BOBN; nxa0=xa053; 19% Brahman and 31% Africander) sires. Calves of Angus (AN) dams were sired by Hereford (HEAN; nxa0=xa038) and Bonsmara (BOAN; nxa0=xa045; 31% Africander) sires. Carcass yield and LM area were greater (Pxa0 xa00.15) in Warner-Bratzler shear force values. Presence of Brahman breeding (BN) in the dam breed positively affected weight traits, whereas absence of Brahman breeding (AN) positively affected carcass merit traits. In terms of sire breed contributions, neither extent nor source of tropical adaptation provided a distinct overall advantage in this study.