Efeito da estrutura de uma pastagem hibernal sobre o comportamento de pastejo de novilhos de corte

Abstract

RESUMO -Avaliou-se o efeito de diferentes estruturas da pastagem, provocadas pela imposição de dois níveis (tratamentos) de biomassa de lâminas foliares verdes (MSFV) -350 e 600 kg/ha de matéria seca (MS) -sobre o comportamento de pastejo dos animais em pastagem consorciada de aveia preta (Avena strigosa Schreb.) e azevém anual (Lolium multiflorum Lam.). As atividades dos animais foram registradas nos meses de agosto e setembro, em períodos de 24 horas consecutivas, por observadores treinados. Nas horas do dia em que o pastejo é mais intenso, foram avaliados o tempo de permanência nas estações de pastejo, a distância entre as estações alimentares e a freqüência com que os animais permaneciam em um sítio de pastejo. Houve preferência marcante por sítios localizados nos quadrantes de cada potreiro mais próximos dos bebedouros/fontes de água. O tempo de permanência dos animais nas estações de pastejo e a distância entre elas foram similares entre os dois tratamentos. O tratamento de 350 kg/ha de MS de lâminas foliares verdes não se constituiu como um nível de biomassa que afeta o tempo de permanência nas estações de pastejo. Palavras-chave: estações alimentares, sítio de pastejo, lâminas foliares Effect of Structure of a Cool Season Pasture on Grazing Behaviour of Beef SteersABSTRACT -The effect of different pasture structures imposed by treatments of green leaf lamina biomass (GLLB) levels of 350 and 600 kg/ha of dry matter (MS), over animals grazing behaviour was evaluated in this experiment. The pasture was oat (Avena strigosa Schreb.) and Italian ryegrass (Lolium multiflorum Lam.). Animals activities were recorded in August and September, in 24 consecutive hours, by trained observers. In the hours of the day in which grazing were more intense, grazing stations remaining time, distance between feed stations and the frequency of remaining in each grazing site were recorded. Preference for sites located nearest to drinking points were found, in each paddock. Distances between feeding stations and time of remaining in these were similar for both treatments. The treatment with 350 kg/ha of DM of GLLB was not a biomass level that affect remaining time in grazing stations.

Behavior pattern of beef heifers supplemented with different energy sources on oat and ryegrass pasture

“…The permanence of the heifers at feeding stations presented an average of 8.51 seconds, which is a result expressively lower than the 18.62 seconds reported by Trevisan et al (2005) with steers kept at two levels (350 and 600 kg DM/ha) of green leaf blade biomass on oat + ryegrass pastures. Those authors cite that accessibility of green leaves at pasture superficial heights, by its spatial distribution, and the leaf:stem ratio over pasture growth cycle may interfere in the time that the animal uses for forage ingestion at a grazing station.…”

Ingestive behavior and displacement patterns of beef heifers on Italian ryegrass pasture

“…In natural grassland, Gonçalves et al (2009) reported that heifers remained 6.6 seconds at each feeding station, carrying 6.5 bites in each one. On steers grazing oats plus ryegrass pasture, Trevisan et al (2005) Table 4 -Ingestive behavior components and beef heifers displacement for supplemented animals (S) and for those that received no supplement (P) on Italian ryegrass pasture 19.1 seconds of permanence in each feeding station in August and September, respectively, without interference of tested levels of leaf blades biomass. Heifers exclusively on pastures walked 8473 steps/day, 1674 more than the supplemented ones (P=0.0281).…”

Comportamento ingestivo de cordeiras em pastagem consorciada de inverno sob diferentes intensidades de desfolha

“…Esses dados sugerem que o período da tarde é o momento de maior seletividade durante as 24 horas de pastejo. Trevisan et al (2005) avaliaram ofertas de lâminas foliares em azevém pastejado por novilhos e não observaram diferença entre os …”