PERFORMANCE AND BLOOD-CHEMISTRY IN LAMBS FOLLOWING FASTING AND TRANSPORT

Thirty-six 5-month-old Dorset ram lambs (28 . 7 kg) were used to inves tigate the effects of fasting and transport on performance and selecte d blood parameters. Three treatment groups (no. = 12) were: (1) contro l-food and water, without transport; (2) fasting for 72 h, without tra nsport; and (3) transport in a trailer to a nearby auction-barn, then driven 8 h/day for 3 days without food or water for a total of 72 h. L ambs were given a total mixed diet containing 163 g/kg crude protein t hroughout the 28-day post-transport period. Both fasted and transporte d lambs consumed less food than the control group during the first 7 d ays post treatment (P < 0 . 05). Water intake was similar for all trea tment groups on the 1st day post transport, after which both fasted an d transport lambs drank less water than control lambs during the follo wing 6 days (P < 0 . 05). Live-weight loss after the 3-day fast and tr ansport period and subsequent body-weight gain during the 28-day reali mentation period differed across all treatment groups (P < 0 . 05 and P < 0 . 09; (1) 1% and 305 g, (2) 148 . 0 and 343 g, and (3) 20 . 0% a nd 390 g, respectively, though control lambs had the highest weight ga ins over the 32-day experimental period. Plasma urea nitrogen was lowe r in both fasted and transported lambs on days 6, 7 and 11 compared wi th control lambs (P < 0 . 05). Plasma glucose concentrations on days 4 and 5 were lower in transported lambs than in fasted lambs, and highe st in control lambs (P < 0 . 05); glucose concentration levels remaine d lower in both fasted and transported lambs than in control lambs on days 6 and 7 (P < 0 . 05). Plasma cortisol concentrations were highest in transported lambs during the 3-day transport period and for 2 days in immediately following transport (P < 0 . 05). Effects of the 72 h fast were exacerbated by auction born activity and subsequent transpor t, and compensatory gains by fasted and transport lambs were incomplet e within the 28-day post transport period.