Effects of restricted availability of drinking water on body weight and feed intake by Dorper, Katahdin, and St. Croix sheep from different regions of the USA

Abstract

Resilience to restricted availability of drinking water was evaluated with 44 Dorper (DOR; initial age = 3.7 ± 0.34 yr), 42 Katahdin (KAT; 3.9 ± 0.36 yr), and 42 St. Croix (STC; 2.7 ± 0.29 yr) sheep from 46 farms in 4 regions of the USA (Midwest, MW; Northwest, NW; Southeast, SE; central Texas, TX). Ad libitum water intake was determined during 2 wk of period 1, with 75% of this amount offered in 2 wk of period 2 and 50% in 5 wk (i.e., 5 to 9) of period 3. Body weight and DMI in week 2 of period 1 and week 9 of period 3 were analyzed with a mixed effects model. There was a breed × period interaction (P = 0.023) in water intake relative to BW (6.17, 6.69, and 7.19 in period 1 and 3.04%, 3.26%, and 3.36% BW in period 3 for DOR, KAT, and STC, respectively; SEM = 0.219). There were 3-way interactions of breed, region, and period in BW and DMI in g/d (P < 0.010). For STC, BW was greater (P < 0.05) in period 3 vs. 1 for all regions (50.1, 47.6, 42.4, and 45.8 kg in period 1 and 51.9, 49.3, 44.5, and 47.7 kg in period 3), whereas there was only a period difference for DOR from the MW and SE (61.4, 66.0, 64.6, and 59.6 kg in period 1 and 60.6, 66.5, 65.7, and 62.4 kg) and for KAT from TX (50.1, 47.6, 42.4, and 45.8 kg in period 1 and 51.9, 49.3, 44.5, and 47.7 kg in period 3 for MW, NW, SE, and TX, respectively; SEM = 2.57). In accordance, DMI by STC was similar (P > 0.05) between periods for all regions (1.25, 1.17, 1.06, and 1.16 kg/d in period 1 and 1.12, 1.08, 1.02, and 1.02 kg/d in period 3), as was also the case for DOR from MW and SE but not from NW or TX (1.54, 1.50, 1.30, and 1.41 kg/d in period 1 and 1.41, 1.13, 1.25, and 1.18 kg/d in period 3) and KAT from TX though not from the other 3 regions (1.47, 1.52, 1.48, and 1.40 kg/d in period 1 and 1.06, 1.15, 1.30, and 1.33 kg/d in period 3 for MW, NW, SE, and TX, respectively; SEM = 0.061). In conclusion, based on BW and DMI with water intake restricted at 50% of ad libitum consumption by individual animals, STC appeared more consistent in display of high resilience to restricted water availability, although DOR from 2 regions and KAT from 1 also were relatively resilient. The results suggest benefit to breed comparisons of inclusion of animals from multiple areas and that environmental conditions of regions may have disparate effects with different breeds of hair sheep.

Effects of water restriction on feed intake, digestion, and energy utilization by mature female St. Croix sheep

“…The NDF concentration of 33.6% was similar to that noted by Tadesse et al. (2019b) ; 34.2%) though lower than reported in other experiments (36.9, 37.7, and 42.4% in Hussein et al. (2020) , Tadesse et al.…”

“…The chemical composition of the diet ( Table 1 ) was fairly similar to that of the same diet used by Hussein et al. (2020) and Tadesse et al., (2019a , Tadesse et al., 2019b , Tadesse et al., 2019c ) in studies of the same project, but the CP concentration was slightly greater (19.4 vs. 17.3–18.2%).…”

“…, 1.4 kg, SED of 0.29). However, Hussein et al. (2020) noted greater BW in the fifth week of an experiment when drinking water availability was limited to 50% of earlier ad libitum intake of St. Croix from each of the four regions (differences of 1.7–2.1 kg), Dorper from two of the regions (differences of 2.2 and 2.5 kg), and Katahdin from one region (difference of 2.8 kg).…”

“…A possible reason for relatively high variability is that the animals were derived from four areas of the USA with different climatic conditions. As described by Hussein et al. (2020) , regions were the Midwest (portions of Iowa, Minnesota, Wisconsin, and Illinois), Northwest (primarily Oregon with one farm in southern Washington), Southeast (Florida), and central/eastern Texas.…”

“…(2019c) conducted a study with hair sheep to determine effects of restricted feed intake on digestibility and energy utilization to help explain effects on variables such as BW observed in a companion study with a relatively large number of hair sheep of different breeds from regions of the USA with varying climatic conditions. Similarly, Hussein et al. (2020) evaluated resilience of the same hair sheep to availability of drinking water limited to 50% of prior ad libitum consumption.…”