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Herbage Intake (herbage + intake)
Selected AbstractsThe influence of strain of Holstein-Friesian dairy cow and pasture-based feeding system on grazing behaviour, intake and milk productionGRASS & FORAGE SCIENCE, Issue 1 2007S. McCarthy Abstract A comparative study of grazing behaviour, herbage intake and milk production of three strains of Holstein-Friesian dairy cow was conducted using three grass-based feeding systems over two years. The three strains of Holstein-Friesian cows were: high production North American (HP), high durability North American (HD) and New Zealand (NZ). The three grass-based feeding systems were: high grass allowance (MP), high concentrate (HC) and high stocking rate (HS). In each year seventy-two pluriparous cows, divided equally between strains of Holstein-Friesian and feeding systems were used. Strain of Holstein-Friesian cow and feeding system had significant effects on grazing behaviour, dry matter (DM) intake and milk production. The NZ strain had the longest grazing time while the HD strain had the shortest. The grazing time of cows in the HC system was shorter than those in both the HS and MP systems. There was a significant strain of Holstein-Friesian cow by feeding system interaction for DM intake of grass herbage and milk production. The NZ strain had the highest substitution rate with the HP strain having the lowest. Hence, response in milk production to concentrate was much greater with the HP than the NZ strain. Reduction in milk yield as a consequence of a higher stocking rate (MP vs. HS system) was, however, greater for the HP and HD strains compared with the NZ strain. The results suggest that differences in grazing behaviour are important in influencing DM intake and milk production. [source] Production and behavioural responses of high- and low-yielding dairy cows to different periods of access to grazing or to a maize silage and soyabean meal diet fed indoorsGRASS & FORAGE SCIENCE, Issue 4 2006O. Hernandez-Mendo Abstract The study examined whether high-yielding cows grazing pasture respond differently from low-yielding cows in milk production and feeding behaviour, to increasing the time made available for eating a maize silage and soyabean meal (TAMS) diet indoors and reducing the time available for grazing (TAG). Two experiments, each lasting 42 d, were carried out in spring (Experiment 1) and autumn (Experiment 2) using Holstein-Friesian cows at two different levels of milk yield (MYL). Milk production and feeding behaviour were examined for TAG + TAMS systems of 19 h, TAG plus 1 h TAMS (19 + 1), and 5 h TAG plus 15 h TAMS (5 + 15). There were two levels of concentrate (0 and 6 kg d,1), and in the spring experiment two sward heights (4,6 and 8,10 cm) were also studied. Milk yield, persistency of milk yield, liveweight change and estimated total DM intake were significantly higher on the 5 + 15 than on the 19 + 1 grazing system in Experiment 1 but not in Experiment 2. There were no significant interactions of TAG + TAMS treatment with MYL for any production or behavioural measurements except for maize silage feeding time, where high MYL cows spent a significantly greater time eating maize silage than low MYL cows on the 5 + 15 treatment but not on the 19 + 1 treatment. It can be concluded that high- and low-yielding cows respond similarly in milk production and feeding behaviour to different combinations of TAG and TAMS. In autumn, estimated daily intakes of herbage were lower on both grazing treatments relative to spring, resulting from lower rates of herbage intake with no compensatory increase in grazing time. In contrast, rates of intake of maize silage were higher in autumn especially on the 19 + 1 system. These results may imply a change of preference from herbage to maize silage between spring and autumn. [source] Analysis of a Japanese Black Cattle-rearing system utilizing a bahiagrass (Paspalum notatum Flügge) pasture: 3.GRASSLAND SCIENCE, Issue 3 2006Intake from pasture Abstract A Japanese Black Cattle-rearing system utilizing a bahiagrass (Paspalum notatum Flügge) pasture in coastal Miyazaki, southern Japan, was analyzed in terms of intake from pasture. In a field approach, herbage intake by grazing cattle was measured for nine periods (1,5 days) during a grazing season (May,October) along with some other variables (e.g. air temperature, herbage mass, digestibility of grazed herbage), under varying levels of supplementary feeding. The intake from the pasture was most closely related to the intake of supplement, showing a negative linear response at a substitution rate of 0.736,0.750. The intake under no supplementation, i.e. a maximum intake from the pasture, was lower than the voluntary intake predicted with feeding standards. In a modeling approach, a semi-mechanistic model for predicting grazing intake was developed using information from the literature as well as the field data. The performance of the model was acceptable. The model showed similar substitution rates (0.64,0.69), and considerable intake restriction (nearly 30%) that is not attributable to limitations by herbage mass, herbage allowance, diet digestibility or air temperature. The results indicate that a low maximal intake by the animals due to low grazing motivation is a major characteristic of the system where supplementation is a usual management practice. [source] Effects of herbage intake on goat performance in the mediterranean type natural pasturesANIMAL SCIENCE JOURNAL, Issue 1 2009Basri H. HAKYEMEZ ABSTRACT This study aimed at identifying changes in natural pastures during the grazing season and investigating the effects of these changes on pasture feeding potential for high yielding dairy goats. During the study, 12 dairy goats were grazed on a 1.5 ha natural pasture for three months from April to June in 2003, 2004 and 2005. The goats were fed 0.5 kg/day of concentrate as a supplement during the grazing season. Botanical composition, herbage production and intake, crude protein (CP), neutral detergent fiber (NDF) and acid detergent fiber (ADF) contents of the pasture were determined. Live weight, milk yield, milk dry matter (DM) and fat content of the goats were monitored. The data were analyzed using a linear model, which evaluated the effects of grazing seasons in each year. Based on the three-year average, 87% of pasture was herbaceous plants and the remaining was shrubs in DM basis with Cistus creticus, Quercus ithaburensis, Pistacia atlantica and Asparagus acutifolius being the major shrub species. The herbage yield in June was significantly lower than in other months in all years (P = 0.001). In all experimental years, the CP content of the pasture decreased but the structural carbohydrates increased as the grazing season proceeded. While live weight was not affected by grazing periods except for 2004 (P = 0.001), milk yield significantly decreased with advancing grazing period (P = 0.001). The results of the present study indicate that natural pasture has a supportive effect in April and May on the milk yield of lactating goats which are in mid-lactation, and suggested that supplementary feeding is required in consecutive grazing periods. [source] Using plant traits to compare sward structure and composition of grass species across environmental gradientsAPPLIED VEGETATION SCIENCE, Issue 1 2004M. Duru Abstract. Plant traits which may give an indication of a plant's strategy for nutrient acquisition and regeneration are known for numerous grassland species. This study aimed to establish whether there is any relationship between two plant traits: specific leaf area (SLA) and number of reproductive tillers, and sward structural characteristics which influence herbage intake by grazers (bulk density and digestibility, leaf:stem ratio). Comparison is made for nutrient-rich (Dactylis glomerata) and nutrient-poor (Festuca rubra) grass species. We hypothesized that these traits are responsive to environmental gradients and also act on the processes of the ecosystem. Both grasses were compared with two P-fertilizer rates in two localities (200 and 1300 m a.s.l.) which differed in their temperature:radiation ratios. For the vegetative phase SLA was well correlated with sward characteristics: D. glomerata, which has the higher SLA, has the lower bulk density and higher digestibility. The values of SLA and vegetation bulk density varied according to growing conditions (P-rate and temperature:radiation ratio), but the ranking of the species remained the same because the phenotypic plasticity that exists for plant traits was also observed for sward structure and composition. That suggested the possibility of grouping natural grassland species for their relevant characteristics for grazers according to SLA values. Over the reproductive phase, the proportion of stems was well correlated to the percentage of reproductive tillers. However, the percentage of reproductive tillers was a very plastic trait for both species, depending on the growing conditions, and resulting in a density-dependent effect, particularly for F. rubra. The species studied were too plastic and too similar in their regenerative strategy so that there is no unique relationship between percentage of reproductive tillers and stem proportion, regardless of the species and the growing conditions. The number of reproductive tillers is not a suitable plant trait which could be used to rank species for leaf and stem proportions in the sward. [source] | ||||||||||