The objective this study was to evaluate three supplementation strategies on yield
characteristics of the pasture and its reflection in animal production. Was also
evaluated the effect of supplementation strategies in feeding behavior of grazing
cattle. The experiment was conducted at the Federal University of Tocantins, in the
School of Medicine and Animal Science Veterinary and Animal husbandry –
University Campus of Araguaína-TO. 18 beef cattle were used, males, with initial
weight of 291 kg. The animals were kept in 4.8 ha of Piata grass (Urochloa brizantha
cv. Piata), from January to May 2014. The pasture was divided into 24 plots of 0.2
hectares, managed under intermittent grazing with period variable rest being applied
60 kg/ha P2O5 at baseline and 50 kg/ha of NK each grazing cycle. The control
treatment of animals received mineral supplementation at will, and the animals of
energy treatments (ES) and protein-energy (PES) received 2g daily supplement for
each kilogram of body weight. The average daily gain (ADG) was higher for the
animals supplemented with SPE and SE in relation to MS, and of 1,097; 0.974 and
0.831 kg/animal/day, respectively. Highest total weight gain and by area and
increased stocking rate was observed for the PES and ES strategies. The stocking
rate was 4.78; 4.56 and 3.84 AU / ha, to the strategies of PES, SE and MS,
respectively. The additional weight gain of the animals receiving PES and ES was
0.266 and 0.143 kg / animal / day, respectively, compared to MS. Due to the
supplementation, grazing behavior has changed. The grazing time (PT), rumination
(TR) and other activities (OA) were modified by supplementation strategies, and
observed higher PR and lower TR and OA in the output condition, with average TP
105.56 minutes more and TR and AO 53.33 and 52.22 minutes less with respect to
the input condition, regardless of supplementation strategy. A more meals with less
time per meal was found in a condition of entry over the output averaged nine meals
with an average time of 48.32 minutes. The highest rate of TB-bits (bits / second)
was observed in a condition of entry, with an average of 41.84 bits / second, but the
total number of output bits was higher in condition, with an average of value
9
20287.98 bits. Due to increased TB, the number of bits and the time per feeding
station (s) were higher in the input condition, with an average of 9.70 bits with time of
13.84 seconds per feeding station. Due to the MMaller amount of forage in the
condition close to the end of the busy period, the animals increases the total number
of feeding stations, and consequently cover a greater area looking for grazing
favorable sites. The strategic supplementation of grazing cattle is an economically
viable alternative for growing in the rainy season and the choice supplementation
strategy must take into account the objectives to be achieved, the quality of available
forage and the desired economic results.
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