Marcos Weber do Canto

Avaliação de uma pastagem de Coastcross-1 (Cynodon dactylon (L.) Pers) sob diferentes níveis de matéria seca residual

O experimento foi realizado no periodo de agosto de 1997 a abril de 1998, com o objetivo de avaliar uma pastagem de Coastcross -1 (Cynodon dactylon (L.) Pers), em quatro niveis de residuo de materia seca (RMS: 1978, 2130, 2545 e 3857 kg de MS/ha), com lotacao continua e carga animal variavel. Foram determinadas a producao de materia seca (PMS), a taxa de crescimento do pasto (TC), a acumulacao liquida de MS (ALMS), a altura das plantas (AP), a porcentagem de solo descoberto (SD), a participacao dos componentes botânicos na pastagem em porcentagem de material morto (MM) e de folhas verdes (FV), a relacao folha/colmo (F/C) e a quantidade de folhas verdes/ha (FV/ha). Foi utilizado o delineamento inteiramente casualizado, com duas repeticoes. A PMS e TC nao apresentaram relacao significativa com os niveis de RMS e os dias de utilizacao da pastagem. A AP aumentou linearmente com o incremento dos niveis de RMS e decresceu de forma linear com o passar dos dias de experimento. A porcentagem de SD e MM decresceu linearmente, a medida que aumentou o RMS na pastagem, mas elevou-se no decorrer dos dias de experimento em todos os RMS. Para a relacao F/C, porcentagem de FV e a producao FV/hectare, ocorreu comportamento linear semelhante, aumentando conforme o aumento dos niveis de RMS e diminuindo ao longo do periodo do experimento.

Perdas de forragem em capim-Tanzânia (Panicum maximum Jacq cv. Tanzania-1) manejado sob diferentes alturas sob pastejo

The experiment was conducted to evaluate, the forage losses and litter accumulation, in a pasture of Tanzania grass (Panicum maximun Jacq cv. Tanzania) managed in different sward height levels. The studied levels of sward heights (treatments) were: 29.8, 32.0, 47.1, 51.5, 57.9, 62.7, 72.6 and 80.0 cm, in a completely randomized design and two replications. The litter accumulation rate, litter accumulation and forage losses were similar in all heights. The percentage of senescent forage in the plant canopy was influenced on a quadratic way by the sward height levels. The results show that the litter accumulation and forage losses were high, with average DM of 38.9 kg/ha.day and 2179 kg/ha of DM, respectively. Due to the possibility to reduce the pasture persistence and plant structure deteriorate, it is not recommended to utilize Tanzania grass pastures, in levels sward height near or equal of 20 and 80 cm, under continuous stocking rate.

Valor nutritivo do capim-Tanzânia (Panicum maximum Jacq. cv. Tanzânia-1) pastejado em diferentes alturas

Crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg) and in vitro dry matter digestibility (IVDMD) contents were assessed in the leaf blade and stem + leaf sheath fractions of Tanzaniagrass (Panicum maximum Jacq. cv. Tanzania-1) managed at four sward heights (20, 40, 50 and 65 cm). The grazing method was the continuous stocking and variable stocking rate, and used Nelore steers with an average weight of 340 kg. The completely randomized experimental design was used with two replications, and five evaluations were performed during a period of 112 days. The CP, IVDMD, Ca, P and Mg contents decreased while NDF, ADF and K concentrations increased in the leaf blade and stem + leaf sheath fraction in response to grazing height as well as period of evaluation. Leaf blades exibited higher quality than stem + leaf sheath regardless of grazing height and evaluation time. Tanzaniagrass grazed to 40 and 50 cm presents good chemical composition and IVDMD.

Forage production of Tanzaniagrass (Panicum maximum Jacq. cv. Tanzania-1) grazed at different heights.

This experiment was conducted out to evaluate the forage mass (FM), green leaf lamina mass (GLLM), green stem + leaf sheath mass (GSSM), mass of dead material (MDM), green forage mass (GMF), total forage mass (TFM), leaf/stem ratio (L/S), dry matter accumulation rate (DMAR), leaf area index (LAI), % of bare soil (BS) and litter cover percentage (LCP) in Tanzaniagrass pasture (Panicum maximum Jacq. cv. Tanzania-1) managed at four different sward heights (20, 40, 60 and 80 cm). The grazing method was the continuous stocking with variable stocking rate, and the grazing animals were Nellore steers with average weight of 340 kg. The completely randomized design was used with two replications and five evaluation periods were performed. The GLLM, GSSM, MDM, GMF, FM, LAI, DMAR, and TFM increased by increasing of the pasture height, the percentage of NCS, SCWL and dead material decreased with the pasture height. Tanzaniagrass management, based on the pasture height from 40 to 60 cmshowed good morphologic composition and high leaves availability for grazing, good ground cover and dry matter accumulation rate, while the heights of 20 and 80 cm shall not be recommended for the Tanzania grass management when the objective is high production of forage quality.

Sward characteristics of deferred tanzania grass under different height levels, in the winter time

The study was carried out in the county of Astorga, PR, Brazil, in the Nossa Senhora de Aparecida farm. The objective was to study the sward characteristics and forage accumulation of tanzania grass, deferred and after grazed from 07/23 to 09/18/1999, under different sward height levels. The experimental design was a completely randommized, with two replications. The treatments were four levels of sward height: T1=20, T2=40, T3=60 and T4=80 cm. However, the true sward height levels were used for analysis statistics; T1R1=26,3, T1R2=24,6, T2R1=47,9, T2R2=42,5, T3R1=55,8, T3R2=61,7, T4R1=69,2 e T4R2=71,4 cm. Results indicate that: forage mass and green culm mass increased of the positive linear way with increased of sward height. There was no effect of sward height levels on the forage accumulation.

Produção Animal no Inverno em Capim-Tanzânia Diferido no Outono e Manejado em Diferentes Alturas de Pasto

ABSTRACT - The experiment was conducted to evaluate the average daily liveweight gain (ADLG), number of animal.days/ha (AD/ha)and liveweight gain/ha (LG/ha), in a Tanzaniagrass pasture deferred in different sward heights in the autumn and after managed in differentsward height conditions, during the winter period. A completely randomized design was used. The treatments were four levels of swardheight: T 1 =20, T 2 =40, T 3 =60 and T 4 =80 cm. However, the average sward height levels maintained in a pasture was used for thestatistical analysis, and these were: T 20 R 1 = 26.3, T 20 R 2 = 24.6, T 40 R 1 = 47.9, T 40 R 2 = 42.5, T 60 R 1 = 55.8, T 60 R 2 = 61.7, T 80 R 1 =69.2 and T 80 R 2 = 71.4 cm. The different sward heights were maintained under continuous stocking method and variable stocking rate.The ADLG decreased as the sward height levels increased. There was no effect of sward height with LG/ha and number of animal.da ys/ha.The results showed that Tanzaniagrass pastures in the northwest region of Parana, deferred after reproductive phase, could be u sedin 40 to 60 cm of sward height.Key Words: average daily liveweight gain, continuous stocking, grazing management,

Produção de cordeiros em pastagem de azevém e trevo-branco sob diferentes níveis de resíduos de forragem

The objective of this research was to analyse the effects of different forage mass levels on lamb production. The experiment was conducted in Tupancireta, Planalto Medio region at the State of Rio Grande do Sul, Brazil, in a mixture of italian ryegrass cv. Estanzuela 284 (Lolium multiflorum Lam.) + white clover cv. Yi (Trifolium repens L.), under different forage mass (FM) levels. The experimental design used was completely randommized, and the FM levels studied were: 1,119, 1,320, 1,477, 1,695, 2,146, 2,166, 2,410 and 2,483 kg/ha of dry matter (DM - kg/ha). The experimental period was from September 30 to December 8, 1992 and the animals used were cross lamb Ile de France x Corriedale early weaned (mean ± 80 days). Were evaluated the daily liveweight gain (DLG), gain per hectare (G/ha), stocking rate carryed, animals.day/ha and the DM of conversion efficience in kg of lamb liveweight. The results showed a positive linear relationship between DLG and G/ha with increased of FM levels. The FM levels higher to 2,400 kg of DM/ha reached 497 kg of total lamb liveweight gain/ha, and DLG/lamb of 0.12 kg/day. There was no FM levels effect at the stocking rate and animals.day/ha; there was a negative linear relationship between DM of conversion efficience with FM levels studied. The results show the effect of FM levels on animal response.

Animal production in Tanzania grass swards fertilized with nitrogen

Nitrogen (N) at 100, 200, 300, and 400 kg ha-1 was applied to Tanzania grass swards to evaluate the animal response and relationships between sward characteristics and the performance of young Nellore bulls (Bos indicus) under continuous stocking. A completely randomized experimental design was used with two replications between 11 November 2001 and 15 April 2002 when the sward heights were maintained at 60 cm by using different stocking rates. The average daily gain (ADG) (0.73 kg d-1) was not affected by N doses while the number of animal days ha-1 increased linearly from 515 to 1267. On the other hand, the linear increase in the animal yield was 399, 653, 755, and 895 kg ha-1 for N at 100, 200, 300, and 400 kg ha-1, respectively, while the ratio between the liveweight gain (kg) and N (kg ha-1) decreased. Correlation coefficients between ADG and herbage mass, green leaf mass, green herbage mass, proportion of green leaf and leaf:culm ratio were low and nonsignificant. Under the conditions in Northwestern Parana, the application of N to swards of Tanzania grass is a management option for increasing beef cattle production.

Características do pasto e acúmulo de forragem em capim-tanzânia submetido a alturas de manejo do pasto

The objective of this experiment was to evaluate different sward height (20, 40, 60 e 80 cm) in Tanzania grass (Panicum maximum Jacq.) pastures managed under continuous stocking. The animals used were Nellore steers, and the control of sward height was done with put-and-take techniques. Evaluations were made for: forage mass, green leaf mass, leaf:stem ratio, morphological composition and dry matter accumulation rate. The experimental design was completely randomized with two replications. Forage mass increased linearly with sward height with overall mean of 2,767, 3,105, 3,657 and 4,436 kg ha-1 at sward heights 20, 40, 60 and 80 cm, respectively. Rates of dry matter accumulation decreased with increasing sward heights and were 104, 108, 90 and 81 kg ha-1 per day for sward heights 20, 40, 60 and 80 cm, respectively. Leaf:stem ratio decreased linearly with sward heights. Tanzania grass pastures, under continuous stocking, should be managed between 40 and 60 cm heights in the final of spring and during summer station.

Efeito de Estratégia de Suplementação com Concentrado no Desempenho de Cabras Mestiças Saanen, em Dois Sistemas de Produção

The experiment was carried out to evaluate the performances of cross breed Saanen dairy goats submitted to two strategies of supplementation with concentrate 30% of daily requirements in net energy (NRC, 1981) supplied by concentrate, from third week until the end of lactation (ESC.1) or 60% of requirements from the 3 rd to the 13 th week of lactation and 15% from 14 th until the end of lactation (ESC.2); and evaluate the animal response to these strategies of supplementation with concentrate in a semi-confined or pasture systems. Thirty one animals were used in a completely randomized design. The system of production affected the total intake of concentrate and total milk production; at pasture system the values for these two variables were higher. The supplementation with concentrate affected the total intake of concentrate and total production of milk and the relation of milk/consumption of concentrate. The highest value for relation of milk/consumption of concentrate and the least for the total consumption of concentrate were obtained at ESC.1. Body weight affected of the system of production, resulting in a higher value to the system of pasture. Weight and body condition had different responses to he supplementation with concentrate according to the system of production. The semi-confined system ESC.2 resulted in a higher value to the body condition; the body weight was no affected. At pasture system the highest values for weight and body condition were obtained in the supplementation with concentrate ESC.1. Reproductive parameters did not affect supplementation with concentrate and system of production.