Grazing Behavior of Ruminants and Daily Performance from Warm-Season Grasses

Abstract

The various ingestive behavioral measurements have seldom been used to estimate long-term DM intake or to An estimate of the animal-production potential of pastures can be explain differences in intake on daily animal responses assessed by knowing the daily dry matter (DM) intake of the grazing animal and the digestibility of the DM consumed. The objective of among grazing management strategies in a production this paper is to examine the relationships between pasture canopy setting. This is also true relative to predicting daily anicharacteristics, ingestive behavior, and daily animal response from mal response. This need has been previously noted warm-season pastures. Of daily DM intake and digestibility of the (Hodgson, 1982a;Hodgson et al., 1994) and attributed, DM consumed, the former is the most variable and the most difficult in part, to a failure to see the role of ingestive behavior to determine. One approach to estimating daily DM intake has been measurements in production systems (Cosgrove, 1997). to use the components of ingestive behavior to determine a short-Several examples of the usefulness of grazing behavioral term intake rate (g min Ϫ1 ), which can be scaled using grazing time data were provided by Cosgrove (1997). One is the (min d Ϫ1 ) to give a 24-h DM intake (kg d Ϫ1 ). This approach has been importance of canopy height of ryegrass-based (Lolium used experimentally with some success, but has not found application perenne L.) pastures in maximizing daily forage intake in production settings. While aspects of ingestive behavior, including ingestive mastication, are common to all grazing ruminants, literature of the grazing animal and an understanding of why it indicates that differences occur among ruminant species and that is important. Another is the importance of leaf area animals ingest different pasture species differently. This results in index, green leaf mass, and associated stem height of plant-animal interactions. Frequently these dynamics are not clearly the canopy in understanding daily forage intake among addressed for cool-season and warm-season pastures in literature regrazing systems. views, which adds undue confusion to the general area. IngestiveThe general lack of application of grazing behavior behavior is discussed relative to animal-and pasture-generated bounds measurements to production systems is neither a critiwhich operate within paddocks and can greatly alter ingestive behavior cism of previous research nor of this general area of estimates. Also presented are relationships between diet particle size, research. It does beg, however, for the incorporation of associated with ingestive mastication, and steer daily gains.

Podolian beef production on pasture and in confinement

“…Herbage height tended (P , 0.10) to be higher in summer. In agreement with Gibb et al (1997) and Burns and Sollenberger (2002), this variable was negatively correlated with bite rate (r 5 20.60; P , 0.001) and positively related to bite mass (r 5 0.55; P , 0.01). In particular, in a Boval et al's (2007) experiment, bite mass increased by 9 mg per additional centimetre of extended tiller length.…”

Suplementação da dieta de bovinos de corte como estratégia do manejo das pastagens

“…A presença de alta proporção de colmos, associada a baixa densidade de folhas dificulta a apreensão, causando decréscimo no tamanho dos bocados, acarretando baixo consumo de forragem (Stobbs, 1973;t'Mannetje & Ebersohn, 1980;Burns & Sollenberger, 2002).…”

Características estruturais e morfológicas de genótipos de Pennisetum sp. sob pastejo no período de seca

“…De acordo com Gomide et al (2001), a seletividade bovina prioriza as folhas verdes, mais novas e de maior valor nutritivo, em detrimento das mais velhas e secas e do colmo. Nutricionalmente, as folhas são a fração mais importante da pastagem e, portanto, características da pastagem relacionadas a esta fração representam os principais fatores que influenciam o consumo e a produção animal sob pastejo (Burns & Sollenberger, 2002).…”