This study assessed the use of pasture attributes to control daily intake and diet quality during progressive defoliation on pastures of Axonopus catarinensis. Three consecutive 12‐day grazing treatments of progressive defoliation were conducted with Brahman cross‐steers. Daily forage intake and defoliation dynamics were assessed using a pasture‐based method. The treatments differed in initial sward height (33, 44 and 61 cm) and herbage mass (1030, 1740 and 2240 kg ha−1). The post‐grazing residual sward height, at which forage intake decreased, appeared to increase with the initial sward height (12·3, 14·6 and 15·5 cm). Steers grazed up to four distinctive grazing strata in all treatments. The depth and herbage mass content of the top grazing stratum were at least five times higher than the lower grazing strata in all treatments. This explains why forage intake decreased when the top grazing stratum was removed in approximately 93% of the pasture area in all treatments, equivalent to approximately 7% of the pasture area remaining ungrazed. We conclude that the residual ungrazed area of the pasture, rather than residual sward height, can be used to develop grazing management strategies to control forage intake and diet quality in a wide range of pasture conditions.

Information is lacking on inheritance of in vitro dry matter digestibility (IVDMD), neutral detergent fiber (NDF), acid detergent fiber (ADF), and hemicellulose (HEM) of tall fescue (Festuca arundinacea Schreb.) seed and their relationship to these quality traits in herbage. if a close relationship were found between seed and herbage quality, indirect selection for improved herbage quality would be effective. Objectives of this study were to evaluate genetic variation for these quality traits and yield of herbage and seed and to examine association of these quality parameters between seed and herbage. Twenty‐three endophyte‐free parents were randomly chosen from a genetically broad‐based population, and their respective half‐sib families were generated. Herbage and seed samples were analyzed for quality parameters using near infrared reflectance spectroscopy. Significant (P < 0.01) variation was observed in herbage for all traits in the summer (immediately after seed harvest) and the fall for parents. There was no significant variation for IVDMD of herbage in summer or fall or for NDF and ADF in the summer for half‐sib families. For seed, all traits had highly significant variation. Narrow‐sense heritabilities for herbage ranged from 0% for IVDMD, NDF, and yield in the summer to 71% for HEM in the summer. Narrow‐sense heritability of IVDMD for seed was 78%. Heritabilities from herbage estimated by genotypic regressions were higher, ranging from 26% for IVDMD in the summer to 80% for NDF. Seed traits had a similar relationship, with genotypic regression heritabilities ranging from 62% for IVDMD to 86% for NDF. Correlation coefficients of quality traits between herbage and seed were low. Data indicated that indirect selection for improved forage quality via the seed is not useful. Selection for herbage quality directly would also be difficult because gains from selection were low.

SUMMARYSugarcane is an important forage resource in sub-tropical and tropical areas as it is used during the winter or dry season when the growth rate of pastures is significantly reduced. The current research study assessed the effect of four vertical sections of sugarcane in a pen trial and the level of sugarcane utilization in a grazing trial on the ingestive behaviour and forage intake of two age groups of steers (1 and 2 years old). The pen trial was comprised of two simultaneous 4 × 4 balanced Latin square designs (one for each age group of animals) of four periods, four animals and four feeding treatments, which consisted of four equal vertical sections of sugarcane. Dry matter (DM) and digestible DM (DDM) intake per kilogram of metabolic weight declined gradually from top to bottom of the sugarcane, with no significant differences between the age groups of steers. This difference in intake was associated with a decline in intake of neutral detergent fibre (NDF) as a proportion of the liveweight of the animal and an increase of total chewing time per kilogram of DM or NDF from top to bottom of the sugarcane. It was concluded that the toughness of plant material played a significant role regulating intake, which was higher for the top sections of sugarcane. In the grazing trial, steers of both age groups grazed down sugarcane in three plots over 9 days. Steers grazed up to four distinctive grazing strata. Digestible DM intake (DDM intake) was high at low levels of horizontal utilization of the top grazing stratum but DDM intake started to decline sharply when this stratum was removed in 0·92 of paddock area (i.e. equivalent to 0·08 of the pasture area remaining un-grazed). It was concluded that the proportion of un-grazed area of the pasture can be used as a grazing management strategy to control forage intake for sugarcane.

Materials and Methods Two hundred and forty flesh chicks of the ROSS variety were randomly selected to be parts of 12 lots of 20 each. Ten (10) diets were prepared as different treatments using crude, boiled and grilled Acacia macrostachya seeds at a rate 5, 10 or 15% including the control diet or treatment. The nine (9) diets (treatments) using Acacia seed were fed to the lots of chicks respectively, but the control diet was repeated three times, in order to determine the best diet. Two durations of breeding were observed. Results At the end of the experiment using 15% boiled seed of Acacia in the diet of chicks resulted in the best weight gained as well as the lowest index of consumption and the best economic profit during the time o the breeding. The 10% feed level of boiled seeds was also better than the control. The worst result was the crude seed fed at 10%.

Evaluación de un sistema de manejo de Axonopus catarinensis en rotación basado en el remanente de forraje no pastado (Renopa)Long-term assessment of a new rotational-grazing management strategy called PUP-grazing (proportion of un-grazed Palabras clave: Consumo de forraje, ganado vacuno, ganancia de peso, manejo del pastoreo, margen bruto. AbstractA new rotational-grazing management strategy called PUP-grazing (proportion of un-grazed pasture, which is the estimated percentage of pasture vegetation without signs of being consumed) was compared with the traditional rotational-grazing management strategy (TGMS, which is based on residual sward height) using Brahman cross steers on Axonopus catarinensis over two periods (2013/14 and 2015/16) in Misiones, Argentina. The proportion of un-grazed pasture for PUP and TGMS was 11.5 and 3.4%, respectively, of the pasture area. Average daily liveweight gain/animal was significantly higher for PUP than for TGMS (606 vs. 420 g/d; P<0.05) while liveweight gain per hectare was 35% greater for PUP (194 vs. 144 kg/ha/period). The gross margin per hectare was much higher for PUP than for TGMS (US$ 85.7 vs. 8.4/ha/period). These results indicate that on A. catarinensis pastures PUP-grazing has the potential for greater animal and economic performance than the TGMS.