Relationships between botanical composition,yield and forage quality of permanent grasslands over the first growth cycle

This study examined the relationships between botanical composition and forage parameters (yield and forage quality variables) in 153 permanent grasslands located in the Massif Central of France. Grasslands were sampled at two vegetation stages in the first growth cycle. Botanical composition, yield, ash, crude protein, neutral detergent fibre, acid detergent fibre, acid detergent lignin, organic matter digestibility (OMD) and voluntary intake (VI) were estimated for each sample. Temporal variability in species–forage parameter relationships were accounted for using innovative multivariate analyses applied mainly in ecological science. Crude protein and OMD were weakly correlated when each harvest time was analysed separately. Species–forage parameter relationships remained stable during the first growth cycle. The stability of these relationships indicates that permanent grasslands dominated by competitive species were associated with high yield and forage quality values whereas permanent grasslands composed of conservative species and/or high proportions of senescent material were associated with high structural carbohydrate values and low yield, OMD and VI values. Based on these relationships, we propose a typology of permanent grasslands along with a set of indicator species enabling non‐specialist botanists to easily classify grasslands for grassland management purposes.     

The effect of different grazing heights on carcass and meat quality characteristics of Nellore cattle fattened in pastures of Convert grass

Carcass characteristic and meat quality from bulls and Nellore steers (n?=?64 total) subjected to different grazing heights (15, 25, 35, and 45 cm) were evaluated isolatedly, under continuous grazing and variable load, in pastures of Convert grass. The experimental period was from May 2015 to June 2017, in an area of 16 ha, divided into 16 paddocks of 1 ha. The experimental design was randomized blocks with four replications. Each paddock was grazed by three animals and regulators, used to adjust grazing heights. The final slaughter weight, hot carcass, and crude protein in the meat of steers were higher when the pastures were managed at 42 cm. When the pasture was managed between 25 and 35 cm in height, greater fat thickness, marbling, muscle:bone and muscle+fat:bone ratio and lower color* of the meat and percentage of bone were found. For the steers, the height of 40 cm provided higher fat thickness and marbling in the meat. The loss during thawing in meat was greater at 28 cm in height. The heights of grazing alter the carcass characteristics and meat of bulls and steers.