Performance and economic viability of feedlot sheep fed different levels of roughage, concentrate, and water

Abstract

The aim of this study was to evaluate performance and economic viability of producing sheep fed different levels of roughage, concentrate, and water. Forty Santa Inês crossbred sheep with an average initial weight of 18.85 ± 2.80 kg and an average age of 5.0 ± 2.0 months were distributed in a completely randomized design with a 2 × 2 factorial arrangement composed of two proportions of roughage and concentrate (30:70 and 70:30) and two levels of water supply (ad libitum, and 50% restriction), with 10 replicates. Water restriction had a negative effect (P<0.05) on the intakes of dry matter and nutrients and total and daily weight gains, regardless of the proportions of roughage and concentrate. Water restriction did not affect (P>0.05) feed conversion or feed conversion. Total weight gain, average daily gain, feed conversion, and feed efficiency were influenced by the proportions of roughage and concentrate. In conclusion, the diet with 70% roughage, associated with a water restriction of 50%, reduced the uptake of energy and protein, compromising the animal performance. The combination of the diet plus concentrate and water restricted to 50% of the free consumption provides a better cost-benefit ratio. Key words: Water intake. Feed intake. Weight gain. Water restriction. ResumoObjetivou-se avaliar o desempenho e a viabilidade econômica da produção de ovinos recebendo diferentes ofertas de volumoso, concentrado e água. Utilizaram-se 40 ovinos mestiços de Santa Inês, não castrados, com peso inicial de 18,85 ± 2,80 kg e idade média de 5,0 ± 2,0 meses, distribuídos em um delineamento inteiramente casualizado, em um esquema fatorial 2 x 2, composto por duas proporções volumoso e concentrado: 30:70 e 70:30 e duas ofertas de água (água à vontade e restrito em 50%) com 10 repetições. A restrição de água causou efeito negativo (P<0,05) no consumo de matéria seca e nutrientes, ganho de peso total e diário, independentemente das proporções de volumoso e concentrado. Não houve efeito (P>0,05) da restrição de água na conversão e eficiência alimentar. O ganho de peso total, ganho médio diário, conversão e eficiência alimentar foram influenciados pelas proporções de volumoso e concentrado. Concluiu-se que a dieta com 70% de volumoso e associada a uma restrição hídrica de 50%, reduz o aporte de energia e proteína, desfavorecendo o desempenho animal. A combinação da dieta com mais concentrado e restrição hídrica de 50% do consumo permite melhor relação custo benefício. Palavras-chave: Consumo de água. Consumo de alimento. Ganho de peso. Restrição de água.

Different roughage:concentrate ratios and water supplies to feedlot lambs: carcass characteristics and meat chemical composition

“…These mechanisms may stimulate ruminants to ingest water while eating or not to eat when dehydrated. In the current study, water restriction reduced water intake (2.88 and 1.53 kg/day for water intake free and water restriction, respectively (Silva et al, 2016)). Forbes (2007) stated that water is the most important nutrient and that its intake is usually twice as much as the animal's DM intake.…”

“…The higher CP intake (113.40 g/day higher proportion of concentrate and 85.75 g/day for low, Silva et al, 2016) resulted in increased weight gain and carcass yield. This increased weight gain is a response to the higher TDN intake (679.91 g/day higher proportion of concentrate and 548.45 g/day for low, Silva et al, 2016), since, as stated by Pereira et al (2015), higher TDN intakes increase microbial protein production. Microbial protein is considered the main source of metabolizable protein (MP) for ruminants (Santos and Mendonça, 2011).…”

“…Water restriction to 0.5 of the daily requirement affected average daily weight gain, total weight gain and final BW ( Table 2). The lower daily DM intake in response to water restriction (724.55 g/day for water restriction and 879.55 g/day for water intake free, Silva et al, 2016) led to a decrease in average daily weight gain, consequently reducing total weight gain and final BW. Jaber et al (2013) reported that DM intake by ruminants may be influenced by changes in the osmolarity of body fluids such as hypovolemia and hyperosmolality due to saliva and gastric juice production.…”

Adaptability of sheep to three salinity levels in different environments

“…Small ruminants use water efficiently because of their small size, optimal utilization of ingested water (Araújo, Voltolini, Chizzoti, Turco, & Carvalho, 2010;Kumar, Singh, Kumar, Sahoo, Naqvi, 2016. ), ability to retain water and excrete dry stools and concentrated urine, high tolerance to water stress (Silva, Araújo, Oliveira, Azevedo, & Furtado, 2016), and tolerance to foods with high salt concentrations (Moreno et al, 2015;Castro et al, 2017) and high salinity water (Moura et al, 2016;Yousfi, Marques, Betti, Araus, & Serret, 2016). Potter (1968) reported that the consumption of high salinity water by sheep might increase the osmotic pressure in the rumen, without affecting the ruminal microbiota, and change the heart and respiratory rate of the animals (Duarte et al, 2014).…”

Ingestive behavior and thermoregulation in sheep fed forage cactus silage undergoing intermittent water supply

“…Given the demand for potable water by the population living in arid and semi-arid regions and the low precipitation associated with a high evaporation in the recurrent periods of drought that affect these regions, many researchers (ADOGLA-BESSA; AGANGA, 2000;CASAMASSIMA et al, 2008;ALAMER, 2009;SILVA et al, 2016) have sought water supply strategies that increase the efficiency in the use of this essential and limited element for animal production.…”