Pedro Lima Monks

Comportamento ingestivo diurno de novilhos em pastejo submetidos a níveis crescentes de suplementação energética

The trial aimed to observe the ingestive behavior of grazing beef steers submitted to different energetic supplementation levels and kept under an improved natural pasture. Thirty eight beef steers without definite breed, aging 12 to 15 months and weighing 159,97 kg were used. Animals were kept under set stocking in a natural pasture improved with Lotus Subbiflorus and invaded with Eragrostis plana Ness. Two levels of ground sorghum grain were offered as an energetic supplement, and treatments consisted of control or without supplement (T0); 0,75% of mean live weight (T0.75), 1,5% of mean live weight (T0.75). Animals were randomly assigned to treatments according to a complete randomized design. Considering the overall mean, diurnal grazing time (P=0.0059), total rumination time (P=0.0013) and walking time (P=0.0076) followed by a quadratic trend in relation to the supplement levels, and showed larger values for control, T0.75 and T1.5, respectively. Diurnal idling followed a positive linear trend with increasing supplementation levels (P=0.0001). Biting rate and total bites number followed linear (P=0.0001) and quadratic trends (P=0.0002), respectively, with increasing supplementation levels. There were no differences for feeding stations visited per minute and for time spent at the trough between treatments.

Morphogenetic characteristics of pearl millet under rotational grazing with different rest periods

A field experiment was carried out to evaluate the morphogenetic characteristics of pearl millet (Pennisetum glaucum (L.) R.Br.), under rotational grazing with the following rest periods between grazings (RP), corresponding to the time required for expansion from: RP 1.5 to 2 leaves, RP 2.5 to 3 leaves and 3.5 to 4 leaves. Morphogenic characteristics were evaluated in four replications of the area (paddocks) and consisted of leaf blade growth, leaf senescence, stem growth, leaf appearance, phillochron and leaf life-span. The leaf blade growth rate was 6.4, 5.8 and 5.3 cm/day, the senescence rate was 0.71, 0.82 and 1.19 cm/day, the stem growth rate was 0.73, 1.42 and 2.2 cm/day, the leaf appearance rate was 0.158, 0.119 and 0.118, the phillochron was 93, 118 and 128 degrees day for the rest periods of 1.5 to 2, 2.5 to 3 and 3.5 to 4 leaves, respectively. The leaf life span was not affected by the rest periods but the meanvalues were much higher than those obtained in previous studies, thus it is not an efficacious parameter to determine rest periods. The accumulated rates of the morphogenic variables for the 1.5 to 2 leaf rest period during the crop cycle determined a higher plant investment in leaves and, consequently, the best morphogenic responses for the forage aspect.A field experiment was carried out to evaluate the morphogenetic characteristics of pearl millet (Pennisetum glaucum (L.) R.Br.), under rotational grazing with the following rest periods between grazings (RP), corresponding to the time required for expansion from: RP 1.5 to 2 leaves, RP 2.5 to 3 leaves and 3.5 to 4 leaves. Morphogenic characteristics were evaluated in four replications of the area (paddocks) and consisted of leaf blade growth, leaf senescence, stem growth, leaf appearance, phillochron and leaf life-span. The leaf blade growth rate was 6.4, 5.8 and 5.3 cm/day, the senescence rate was 0.71, 0.82 and 1.19 cm/day, the stem growth rate was 0.73, 1.42 and 2.2 cm/day, the leaf appearance rate was 0.158, 0.119 and 0.118, the phillochron was 93, 118 and 128 degrees day for the rest periods of 1.5 to 2, 2.5 to 3 and 3.5 to 4 leaves, respectively. The leaf life span was not affected by the rest periods but the meanvalues were much higher than those obtained in previous studies, thus it is not an efficacious parameter to determine rest periods. The accumulated rates of the morphogenic variables for the 1.5 to 2 leaf rest period during the crop cycle determined a higher plant investment in leaves and, consequently, the best morphogenic responses for the forage aspect.

Níveis crescentes de suplementação energética sobre o desenvolvimento de novilhos mantidos em pastagem natural na encosta do sudeste do Rio Grande do Sul

The trial was conducted from August 11th to November 15th, to evaluate the effects of energetic supplementation with ground sorghum grain on grazing beef steers performance. Thirty eight steers without definite breed, aging 12 to 15 months and weighing 159,97 kg were used. Animals were kept under set stocking on a natural pasture improved with Lotus subbiflorus and invaded with Eragrostis planna, Ness. Treatments consisted of control or without supplement (T0); 0.75% of mean live weight (T0.75) and 1.5% of mean live weight (T1.75) of ground sorghum grain. Animals were randomly assigned to treatments according to a complete randomized design. The effects of treatments on animals live weight daily gain (ADG) and increment of body condition score (IBCS) were just observed at the first period, from August 11th to September 6th, and considering the overall mean of the experiment, when a quadratic response was observed. There were no supplementation effects upon increment of height at withers and hearth girth. Supplementation with ground sorghum grain increased ADG and IBCS compared to no supplemented animals at the end of the winter, however, there was no effect during spring.

Características estruturais de milheto sob pastejo rotativo com diferentes períodos de descanso

This work used the necessary time (days) for a completely elongation of new leaves, i.e., 1.5-2.0; 2.5-3.0 and 3.5-4.0 new leaves completely elongated in order to determine the rest period (RP) between grazing in Pearl millet (Pennisetum glaucum (L.)R. Br.). The experiment was carried out as a completely randomized design with four replications (paddocks). Evaluations were performed for: number of live leaves/tiller (NAL); final length blade (FLB); blade/sheath and culm ratio (B/S+C); basal tiller density (BTD) and aerial tiller density (ATD). The higher BTD; NAL and B/S+C ratio observed in the shortest rest period determined the high quantity of green blades in the pasture sward and consequently the best structural characteristics from the forage point of view.

Ganho de peso de novilhos mantidos em pastagem natural na encosta do sudeste do Rio Grande do Sul, recebendo níveis crescentes de suplementação energética

The trial was conducted to evaluate the effects of energy supplementation with ground sorghum grain on grazing beef steers weight gain. Sixty five steers without definite breed, aging 12 to 15 months and weighing an average 140 kg of live weight were kept under set stocking on a natural pasture improved with Lotus subbiflorus. Treatments consisted of control or without supplement (T0); 0.75% of mean live weight (T0.75) and 1.5% of mean live weight (T1.75) of ground sorghum grain. Animals were randomly assigned to treatments according to a complete randomized design. Considering the overall mean of the trial, supplement levels showed a linear positive effect on daily weight gain, of 0.36, 0.52 and 0.76 kg/animal for T0, T0.75 and T1.5, respectively. Energy supplementation resulted in greater weight gains for supplemented animals compared to not supplemented animals, during all the experiment.

Produção e qualidade da forragem do capim-elefante (Pennisetum purpureum Schum.) cv. vruckwona submetido a diferentes épocas de diferimento e cortes

A field experiment was carried out at Capao do Leao, RS, to evaluate the effect of three deferment periods (January 22, February 25 and March 25) and four cutting ) periods (April 22, May 20, June 17 and July 15) on the production and quality of Elephant-grass cv. Vruckwona. A split plot design with four replications was used. Deferment periods were allocated in the main plots and cutting periods in the subplots. Dry matter (DM) and crude protein (CP) productions demonstrated significant differences according to the deferment and cutting periods. The deferment in January presented highest DM and CP production of 8434 and 318kg/ha, as the cutting periods average. The February and March deferment periods had similar DM and CP production, which values of 2112kg/ha and 147kg/ha respectively. The January deferment period was in average 3.8% and 44.1 % and for February was 6.3% and 46.7% for CP and in situ DDM digestibility. CP and DDM percentage values were higher in the first two cutting periods than in the later one, for February and March deferment penods. At the beginning of deferment periods, the DM and CP productions increased from the first to the last cutting period. The deferment period had a more remarkable influence on production and quality of the forage than the cutting period. The determent at the beginning of the Summer increases forage production, however, the quality is low. The deferment at the end of the Summer decreased forage production.

Estabelecimento do amendoim forrageiro e dinâmica de espécies em vegetação campestre no litoral sul, Rio Grande do Sul

The objective of this study was to evaluate the practical application of herbicide, overseeded annual ryegrass for the establishment of forage peanut (Arachis pintoi) in natural vegetation. The experiments was conducted from October 2007 to November 2008, Estacao Experimental Terras Baixas (ETB) - Embrapa Clima Temperado, Capao do Leao - RS. The treatments were arranged in a randomized block design in split plots with four replications. The plots were represented by the treatments with and without herbicide (3L ha-1 of commercial herbicide glyfosate). The subplots were defined by the absence of forage peanut, the presence of forage peanut, the presence of forage peanut overseeded with annual ryegrass. The frequencies of species of natural vegetation were not influenced by grazing and overseeded ryegrass. The establishment of forage peanut Arachis pintoi is benefited by the herbicide. However, it is a practice that causes a significant reduction of species of forage interest. The presence of annual ryegrass provides a favorable environment for forage peanut during the cool season.

Manejo da desfolha de duas variedades de trevo-persa cultivadas em solo hidromórfico

The effects of three frequencies and two intensities of defoliation on the morphogenic and structural characteristics, in the herbage production and leaf/stem ratio of two varieties of persian clover (Trifolium resupinatum L. var. resupinatum Gib & Belli. cv. Kyambro and Trifolium resupinatum var. majus Boiss cv. BRS Resteveiro) were studied. The experimental design consisted of complete randomized blocks in a 2 × 3 × 2 factorial arrangement, with five replications. The following variables were evaluated: leaf appearance rate, phyllochron, leaflet extension and elongation rate, leaflet width and length, number of ramifications, plant height, number of open live leaves, total dry matter production and leaf/stem ratio. Although the forage presented higher number of live leaves in bigger defoliation intervals and the higher forage production was obtained in the residual height of 5 cm and in the interval of 6 leaves appearing, more frequent cuttings provide improvement of the leaf/stem ratio, higher number of ramifications, higher leaf appearance rate and bigger leaflet size.

Suplementação energético-protéica no desenvolvimento corporal de novilhas Jersey em pastejo

The trial was conducted to evaluate the effects of three levels of energy-protein supplementation with corn ground and soybean meal on grazing dairy heifers body development. Fifteen Jersey heifers, aged of 6 to 18 months and weighing 142,2 ± 7,8 kg, were used. Animals were kept under rotational grazing system and fixed stocking rate on a ryegrass and black oats pasture. Animals were classified by their initial body weight and randomly assigned to treatments according to a complete randomized block in a split plot design: 100% corn ground, 70% corn ground + 30% soybean meal, 40% corn ground + 60% soybean meal. Evaluation was performed over six periods of 28 days. No effects for treatments were detected on animals body development attributes as increases in daily live weight gain, total live weight gain, increments of height at withers and heart girt, probably due to high values for pasture quality herbage mass.

Características produtivas da consorciação de trevo-persa e azevém submetidos a pastejo

The aim of this trial was to study the effect of different grazing intervals on productive characteristics of persian clover and ryegrass, in consortium and managed under rotational stocking during the years 2009 and 2010. Treatments were composed of four grazing intervals (time to onset of 2.5; 3.5; 4.5 and 5.5 leaves in persian clover plants) allocated in completely randomized blocks, with six replications. Leaf area index (LAI), leaf area, pasture and plants height, length of tillers/branches, rate of dry matter accumulation and dry matter yield were evaluated. The leaf area index of the canopy and the persian clover was higher in the interval of 5.5 leaves in years 2009 and 2010. In 2009, higher values of leaf area were obtained in intervals of 3.5 and 4.5 leaves and there no was effect of grazing intervals on this variable in 2010. Higher grazing intervals provided greater pasture height and plant height and also greater tiller and branch length. The dry matter production of persian clover was higher in 2010, while for ryegrass highest yields were found in 2009. Total dry matter yield was higher in the interval of 5.5 leaves. The rate of dry matter accumulation was higher in the interval of 5.5 leaves in 2009 and in the interval of 2.5 leaves in 2010. The productive characteristics of a of mixture persian clover and ryegrass are modified by the grazing intervals. It is recommended intervals up to 3.5 of appeared leaves with a mixture of persian clover and ryegrass, which provides lower elongation of stems associated with a lower presence of dead material, which probably improves the quality of the harvested forage.