Denise Baptaglin Montagner

Brazilian scientific progress in pasture research during the first decade of XXI century

This paper aims to discuss the scientific progress obtained in the past ten years in genetics and plant breeding, soil fertility and plant nutrition and the importance of target sward conditions for planning, controlling and recommending management grazing of tropical grasses. In addition, progress in crop-livestock integration systems and management alternatives for mitigation of greenhouse gas emission by beef cattle production systems, two very important areas related to sustainable production systems, will also be discussed.

Suplementação energética na recria de bezerras de corte mantidas em pastagem de inverno

This work was carried outo to evaluate the effect of levels of energetic supplementation in productive and reproductive performance of sixty-four Charolais heifers and their crosses with Nellore, mantained in cultivated pasture of black oat (Avena strigosa Schreb) plus Italian ryegrass (Lulium mulktiflorum Lam.). The treatments considered supplementation of 0; 0.7 and 1.4% of the live weight (LW)/day of rice bran associated with citric pulp, in the proportion of 1:1. A continuous grazing system with variable stocking rate was used, to maintain 1500 kg/ha of DM in herbage mass in all treatments. The following parameters were evaluated: average daily gain, stocking rate, live weight gain, body condition, pelvic area, weight at puberty and age at puberty, hip height and estimated intake of DM. The supplementation increased average daily gain, stocking rate and live weight gain. Heifers kept only on pasture had lower body conditions and showed lower heat percentage than heifers supplemented with 0.7 and 1.4% of LW/day with no differences (P>0.05) between the 0.7 and 1.4% levels. The percentage of heifers showing heat until 16 months of age was 9.1; 68.7 and 70.6%, respectively. The supplementations levels did not affect pelvic area, age at puberty and hip height. The estimated intake of DM was lower for the level of 1.4 % LW/day.

Efeito de níveis de suplementação sobre o comportamento ingestivo de bezerras em pastagem de aveia (Avena strigosa Schreb.) e azevém (Lolium multiflorum Lam.)

Foi avaliado o comportamento ingestivo de bezerras de corte submetidas a diferentes niveis de suplementacao energetica. Os niveis testados foram (0; 0,5; 1,0; 1,5% do peso vivo), em pastagem de aveia preta (Avena strigosa Schreb.) e azevem (Lolium multiflorum Lam.). O suplemento foi farelo de trigo, fornecido diariamente as 14h. Para registro das atividades de pastejo, ruminacao, ocio e permanencia no cocho, adotou-se a observacao visual, feita a cada dez minutos, durante 24 horas, em quatro datas. Para cada nivel de suplementacao, foram observados seis animais dos grupos geneticos Charoles, 3/4 Charoles/Nelore e 5/8 Nelore/Charoles, com aproximadamente oito meses de idade e peso inicial de 158 kg. Os animais que receberam suplementacao diminuiram o tempo de pastejo em relacao aos nao-suplementados, sem alteracao no consumo estimado de forragem. Os animais que receberam suplementacao a 1,5% do PV permaneceram mais tempo no cocho, aumentando a frequencia de retorno ao cocho nos maiores niveis de suplementacao. Os niveis de suplementacao nao interferiram nos tempos de ruminacao e ocio.

Alternativas de utilização da pastagem hibernal para recria de bezerras de corte

The experiment aimed to evaluate animal performance and economic return in oats (Avena strigosa Schreb) plus Italian ryegrass (Lolium multiflorum Lam) pasture subjected at three systems of utilization. The treatments used were: 1. pasture of oat + Italian ryegrass + 300 kg/ha of nitrogen-Nitrogen; 2. pasture of oat + Italian ryegrass + supplementation-Supplement and 3. pasture of oat + Italian ryegrass + arrowleaf clover-Clover. The experimental animals were ninety-four beef heifers of Charolais breed and Charolais-Nellore crosses, with initial weight and age of 197 kg and nine months, respectively. The continuous grazing method with variable stocking rate was used. The supplement utilized was ground sorghum, at quantity of 1% of live weight (LW). The score of body condition (BC), average daily gain (ADG), stocking rate (SR), live weight gain per ha (LWG) and economic return (ER) from treatments were evaluated. The greater BC, SR and LWG were obtained on Supplement, with values of 3.5, 1360.1 kg of LW/ha and 602.8 kg of LW/ha, respectively. The total cost and net income per treatment were R

Suplementos energéticos para recria de novilhas de corte em pastagens anuais: desempenho animal

687.15 and 194.28; 881.49 and 113.13; 574.69 and 226.22 for Nitrogen, Supplement and Clover, respectively. The treatment Clover presented the best ratio, with return of R

Parâmetros produtivos de uma pastagem temperada submetida a alternativas de utilização

1.39 for each one real invested. In biological values, utilization of oat and ryegrass pasture for beef heifers, without impairment of ADG, greater stocking rate and production per area are obtained using energy supplementation.

Desenvolvimento de novilhas de corte submetidas a diferentes sistemas alimentares

It was evaluated beef heifers performance from three until twelve months of age, when they were reared in cultivated pasture soon after their weaning (experiment 1) and in the first winter post-weaning (experiment 2), with or without the supply of energy supplements to the animals. From 02/16 to 04/21/2001, the heifers stayed in Pearl Millet pasture, exclusively under grazing (PAST1); supplemented with milled corn grain (PAST1/C) or supplemented with pellet citric pulp (PAST1/P). From 07/13 to 10/09/2001, the heifers were maintained in oat plus italian ryegrass pasture without supplementation to the animals (PAST2); supplemented with milled corn grain (PAST2/C) or supplemented with soy hull (PAST2/H). The evaluated variables of animal performance were live weight (LW), average daily gain (ADG) and body condition score (BCS). In the experiment 1, supplemented animals presented larger values of final LW, ADG and BCS in relation to the non supplemented, ones the supplemented treatments not differing to each other. In experiment 2, the soy hull supplemented heifers showed greater ADG and final LW than non supplemented heifers, with the corn grain supplemented group in an intermediary position. The highest BCS was obtained by the animals of PAST2/H, followed by PAST2/C and, at last, of PAST2. Beef heifers weaned at 60-90 days should be supplemented in the initial post-weaning period, enabling them to reach satisfactory development in this phase of growth. The by-products citric pulp and soy hull can substitute the corn grain as energy supplements for rearing of beef heifers.

Características produtivas e estruturais do milheto e sua relação com o ganho de peso de bezerras sob suplementação alimentar

This trial was developed with aim of evaluating the productive parameters of a pasture of oat (Avena strigosa Schreb) and Italian Ryegrass (Lolium multiflorum Lam.) submitted to alternatives of utilization. The treatments were: 1 Supplement: pasture of oat + ryegrass + animals fed energy supplementt in a daily quantity of 1.0% of live weight (LW) with nitrogen (N) fertilization of 150 kg/ha; 2 Nitrogen: pasture of oat + ryegrass with N fertilization of 300 kg/ha; 3 Pasture: pasture of oat + ryegrass with N fertilization of 150 kg/ha. The experimental animals were ninety-four beef heifers of the breed Charolais and their crosses with Nellore, with initial weight of 197 kg. The continuous grazing method with variable stocking rate was used. The herbage mass (HM), accumulation daily rate (ADR), total production of forage (TPF), herbage losses (HL) in kg/ha of dry mater (DM) and in percent of live weight (%LW) were evaluated. In the botanical composition of pasture, blade leaf of oat mass (BLM), blade leaf of ryegrass mass (BLR), stem mass (SM), ryegrass inflorescence mass (RIM) and dead material mass (DMM) were evaluated. The green material availability (GMA) and leaf blade availability (LBA) were evaluated by using HM. There was not observed difference among treatments evaluated for HM, GMA, ADR TPF and HL in kg/ha of DM and %LW. The treatments Nitrogen and Supplement presented greater contribution of green leaf than Pasture treatment.

Manejo da pastagem de milheto para recria novilhas de corte

The effect of feeding systems on performance of beef heifers, on period of eight to 18/20 months of age. Charolais heifers and their crosses with Nellore were evaluated. The feeding systems were: Oat + Annual ryegrass + Pearl millet- Black oat (Avena strigosa Schreb) and Annual ryegrass (Lolium multiflorum Lam) and Pearl millet (Pennisetum americanum (L.) Leeke) pasture; Oat + Annual ryegrass + natural pasture- Black oat and annual ryegrass and natural pasture with Annoni grass (Eragrostis planna Nees); Oat + Annual ryegrass + supplementation + pearl millet- Black oat and Annual ryegrass with supplementation and Pearl millet pasture; Oat + Annual ryegrass + supplementation + natural pasture- Black oat and Annual ryegrass with supplementation and natural pasture with Annoni grass. The supplement utilized was ground sorghum on 0.7% of the live weight/day. Live weight, condition score, ovarian activity and number of heifers showing heat on period of 18 to 20 months of age were recorded. Heifers kept only in natural pasture during summer/autumn did not achieve recommended live weight for mating at 18/20 months of age. Heifers cicling were heavier and had greater average daily gain in winter. Heifers kept on Oat + Annual ryegrass + Pearl millet had greater ovarian activity at 18/20 months of age.

Tillering dynamics in pastures of guinea grass subjected to grazing severities under intermittent stocking

The productive and structural characteristics of Pearl millet (Pennisetum americanum (L.) Leeke) under continuous stocking rate and their relationship with beef heifers performance exclusively under grazing (PAST), supplemented with corn grain (PAST + C) or citric pulp (PAST + P) was evaluated. There was no difference among treatments for herbage mass, forage allowance, leaf lamina mass, leaf lamina allowance, daily accumulation rate of forage and herbage total production. Daily accumulation rate of forage, leaf lamina mass and leaf lamina allowance decreased linearly during the grazing period. The participation of Pearl millet components in the sward structure was similar among treatments and changed during the time. The energetic supplementation increased the stocking rate at beginning of grazing, with high leaf lamina participation in the canopy and increased the average daily gain in subsequent periods, with decreasing of the leaf lamina participation. The effect of energetic supplementation on Pearl millet pasture is linked with the amount and distribution of leaf lamina in the canopy structure. The energetic supplementation does not affect the structural and productive characteristics of pearl millet.