Management targets for maximising the short-term herbage intake rate of cattle grazing in Sorghum bicolor

AbstractThe use of forage legumes has been proposed as a means of generating sustainable grazing environments. Their limited use, particularly in tropical pastures, is partially due to the limited knowledge regarding the efficiency of utilization by animals. The present study characterized the sward structure, nutritive value and ingestive behaviour of dairy heifers in pastures of peanut cv. Belmonte under continuous stocking management. Treatments corresponded to sward heights of 5, 10, 15 and 20 cm, according to a randomized complete block design, with four replications. The following response variables were evaluated: vertical distribution of the morphological components within the sward, forage mass, nutritive value (simulated grazing), bite rate (BR), bite mass (BM) and short-term herbage intake rate (STIR). The top half of the sward height was mainly composed of leaves and the bottom half mainly of stolon and dead material regardless of management height. Greater values of neutral detergent fibre and acid detergent fibre were recorded during autumn, while higher values of in-vitro dry matter (DM) digestibility (0·85) occurred during spring regardless of management height for the grazed stratum. In relation to treatments, greater values of crude protein were recorded on swards managed at 5 cm (0·27) and 10 cm (0·26). Bite rate, BM and STIR varied with sward height, but not with a season of the year. The STIR followed a broken line response to sward height, with increasing values up to 13·1 cm (106 g DM/kg body weight). Sward structure played an important role in determining the STIR. To maximize the STIR of dairy heifers under continuous stocking management, swards should be managed at heights of not <13·1 cm.

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Ingestive behavior and short-term intake rate of cattle grazing on tall grasses

Livestock Science ◽

10.1016/j.livsci.2015.07.024 ◽

2015 ◽

Vol 180 ◽

pp. 113-120 ◽

Cited By ~ 1

Author(s):

Masato Yayota ◽

Aki Kato ◽

Megumi Ishida ◽

Shigeru Ohtani

Keyword(s):

Cattle Grazing ◽

Ingestive Behavior ◽

Intake Rate ◽

Short Term

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The determinants of herbage intake by grazing sheep: The interrelationship of factors influencing herbage intake and availability

Australian Journal of Agricultural Research ◽

10.1071/ar9700755 ◽

1970 ◽

Vol 21 (5) ◽

pp. 755 ◽

Cited By ~ 242

Author(s):

WG Allden ◽

IA McDWhittaker

Keyword(s):

Plant Height ◽

Spatial Relations ◽

Initial Increase ◽

Intake Rate ◽

Short Term ◽

Herbage Intake ◽

Constant Rate ◽

Herbage Yield ◽

Grazing Sheep ◽

Animal Size

The interrelationship of characters of the pasture (herbage yield, height of sward) and of the animal (size of animal, rate of intake, rate of biting, size of bite, and time spent grazing) which influence the consumption of herbage by the grazing sheep was examined in three short-term experiments. In one study the high correlation usually observed between herbage yield per unit of land area and plant height was disturbed by manipulating the spatial relations of the sward; it was observed that the rate of intake of pasture by grazing animals was closely associated with plant height (estimated from tiller length) there being little relation between herbage yield and intake. Size of bite increased almost linearly with changing tiller length, whereas after a small initial increase the rate of biting decreased. These differences produced a sevenfold change in the rate of herbage consumption between sheep grazing pastures of 3.7 cm tiller length (1.0 g dry matter/min) and 7.7 cm (7.1 g/min). At greater tiller lengths the size of bite and rate of biting varied inversely to maintain a constant rate of intake. When accessibility of herbage imposed limitations on the rate at which the animal was able to prehend its feed, it was shown that the sheep was able partially to compensate for the reduced amount of herbage present by an increase in grazing time (from 6 to 13 hr/day). However, as the animal extended its period of grazing the compensation became progressively more incomplete. Under sparse pasture conditions lambs were able to consume feed at a significantly greater rate than yearlings but as pasture availability increased the situation was reversed. The role of short-term grazing studies in relation to problems of grazing management is discussed.

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Effects of ruminal fill on short-term herbage intake rate and grazing dynamics of beef heifers

Grass and Forage Science ◽

10.1111/j.1365-2494.2007.00589.x ◽

2007 ◽

Vol 62 (3) ◽

pp. 346-354 ◽

Cited By ~ 38

Author(s):

P. Gregorini ◽

S. A. Gunter ◽

C. A. Masino ◽

P. A. Beck

Keyword(s):

Intake Rate ◽

Beef Heifers ◽

Short Term ◽

Herbage Intake

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Limitations in assessment of forage intake and diet composition of steers grazing tropical pastures with short-term intake rate and oesophageal fistulated steers

BSAP Occasional Publication ◽

10.1017/s1463981500042242 ◽

2006 ◽

Vol 34 ◽

pp. 41-47

Author(s):

H. D. Hess ◽

C.E. Lascano ◽

M. Kreuzer

Keyword(s):

Rainy Season ◽

Daily Intake ◽

Dry Season ◽

Intake Rate ◽

Short Term ◽

Tropical Pastures ◽

Arachis Pintoi ◽

Herbage Intake ◽

The Difference ◽

The Relationship

SummaryTwo grazing trials were carried out to compare the grazing selectivity of oesophageal fistulated and intact steers, and to measure short term grazing behaviour and daily intake of steers in pastures (six pasture types) based on Brachiaria humidicola and Arachis pintoi. During the rainy season, the composition of the pasture affected the proportion of legume in the diet selected by the two groups of steers. The property of the pasture best related to legume selected by the intact steers was the legume mass in the forage available. The proportion selected by the fistulated steers was best related to the proportion of legumes in the pasture. The legume proportion selected by the two groups of steers was related to the bulk density of legumes in the forage, but the type of relationship varied between the groups. The relationship for the fistulated steers was linear, and that for the intact steers was exponential with an asymptote. During the dry season the relationships for the fistulated animals were similar to those observed during the rainy season, but the proportion of legume in the diet of the intact animals was not affected by attributes of the pasture. The pattern of intake in the short term was not affected by the height or amount of forage available during the rainy season, but during the dry season the weight per bite, and short-term intake was related to the height and amount of forage available. Daily herbage intake was not related to short-term intake.The results of the first experiment confirmed that the selection of legumes by grazing steers can vary considerably between intact and fistulated steers. Furthermore it was suggested that the difference resulted partially from the different reactions of the two groups of experimental animals to changes in the attributes of the pasture. The second experiment showed that the daily intake of forage is not necessarily related to intake behaviour in the short term.

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Effect of type of supplement offered out of parlour on grazing behaviour and performance by lactating dairy cows grazing continuously stocked grass swards

Animal Science ◽

10.1017/s1357729800052930 ◽

2002 ◽

Vol 75 (1) ◽

pp. 153-167 ◽

Cited By ~ 5

Author(s):

M. J. Gibb ◽

C. A. Huckle ◽

R. Nuthall

Keyword(s):

Temporal Pattern ◽

Daily Intake ◽

Eating Behaviour ◽

Protein Supplement ◽

Intake Rate ◽

Jaw Movements ◽

Eating Time ◽

Herbage Intake ◽

Supplement Intake ◽

Grazing Behaviour

AbstractTwo 4-week experiments were conducted to examine the effect of type of supplement, offered through automatic feeders at pasture, on supplement intake and grazing behaviour by multiparous spring-calving Holstein-Friesian cows grazing continuously stocked grass pastures. Four supplement formulations were used: a dairy concentrate containing 180 g crude protein per kg fresh weight (treatment DC), a high digestible undegraded protein supplement (treatment HP), a high starch, low protein supplement (treatment HS) and a high fibre supplement (treatment HF). In experiment 1, groups of eight cows were provided with access to one of diets DC, HP or HS, with a maximum of 4 kg being available during each of two periods, between 16:00 and 03:30 h and between 03:30 and 14:30 h. During experiment 2, groups of eight cows were provided access to diet DC, HP, HS or HF, up to a maximum of 8 kg between 16:00 and 14:30 h the following day. Detailed measurements of grazing, ruminating and supplement eating behaviour were made using jaw movement recorders and the transponder-controlled out-of-parlour feeder software. Treatment had no effect on intake rate per min or daily intake of supplement in either experiment, but did affect the temporal pattern of concentrate meals. Treatment did not affect grazing bite mass, bite rate or intake rate in either experiment. During experiment 1, compared with treatment DC, treatment HS reduced total eating time, total grazing jaw movements and daily herbage intake and increased ruminative mastications per bolus and ruminative mastications per kg grass OM intake. In experiment 2, compared with treatment DC, only treatment HS reduced total eating time, total grazing jaw movements and daily herbage intake. Treatments HS and HF both increased ruminative mastications per bolus. The results indicate that when supplements are available at pasture there is a conflict between the time required to consume supplements and herbage and that supplement type can affect both the temporal pattern of supplement intake and subsequent grazing activity.

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PSIX-13 Influence of herbage allowance and beef cow genotype on herbage intake during mid-gestation in Campos grassland

Journal of Animal Science ◽

10.1093/jas/skz258.791 ◽

2019 ◽

Vol 97 (Supplement_3) ◽

pp. 397-397

Author(s):

Martin Do Carmo ◽

Cristina Genro ◽

Andres Cibils ◽

Pablo Soca

Keyword(s):

Beef Cows ◽

Intake Rate ◽

Beef Cow ◽

Herbage Intake ◽

Stocking Rates

Abstract The objective of this study was to measure herbage intake rate (g/kgBW0.75/d) of purebred (Pu, Hereford/Angus) and crossbred (Cr, F1 of Hereford/Angus) beef cows grazing under high (Hi) and low (Lo) annual herbage allowance (HA, mean 5 vs 3 kgDM/kgBW) but equal winter herbage allowance (3 kgDM/kgBW). Herbage intake was measured in 32 gestating cows (from -96 to -76 and -92 to -77 days to calving in y1 and y2 respectively) via n-alkanes C32. Cows were placed in one of 8 groups within 2 blocks (each block four paddocks) of HA x cow genotype treatment. In mid-gestation average herbage mass (±SE) was Hi = 1410 vs Lo = 710 ±230 kg DM/ha (P < 0.05) in y1, and Hi = 850 vs Lo = 570 ±230 kg DM/ha (P = 0.38) in y2. Cow genotype did not affect herbage mass, and CP (8.6±0.37%) and ADF (40.6±1.2%) concentration were not affected by HA. Cow BW (kg±SE) in Hi vs. Lo HA was 478 vs 452 ± 20(P = 0.35) for y1 and 456 vs 393 ± 17(P < 0.05) for y2, while cow BW in Cr vs Pu was 477 vs 453 ± 17 (P = 0.34) and 448 vs 407 ± 17 (P = 0.09) for y1 and y2, respectively. Herbage allowance affected herbage intake (g/kgBW0.75/d) in y2, Hi = 77 vs Lo = 70 ±0.3 (P < 0.05) but not in y1 (Hi = 103 vs Lo = 97 ±0.3, P = 0.19) while Cr cows had lower herbage intake Pu = 108 vs Cr = 92 ±0.3 Cr (P < 0.05) and Pu = 79 vs Cr = 68 ±0.3 (P < 0.05) y1 and y2, respectively. Intake rates were affected by HA and animal genotype. High HA increased intake rates 10% and Cr cows decreased 17% herbage intake rate. Our results provide mechanistic criteria to manage stocking rates on Campos cattle ranches.

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