J. D. Garlich

Effect of fasting and acute heat stress on body temperature, blood acid-base and electrolyte status in chickens☆

1. The tolerance of chickens to acute heat stress, evaluated by the time required to reach the critical body temperature (Tr) of 44.5 degrees C, was markedly enhanced as the period of fasting was extended. 2. Fasting reduced the rates of heat-induced changes in blood acid-base and electrolyte status. 3. Changes in Tr were correlated with changes in blood pH, pCO2, [Cl-] and [Pi] but not with changes in [Na+] or [K+]. 4. Blood acid-base and electrolyte status were related to Tr rather than time of exposure to heat stress.

Glucose and electrolyte supplementation of drinking water improve the immune responses of poults with inanition

Abstract Enteric disorders predispose poultry to malnutrition. The objectives of this paper were 1) to simulate the inanition of poult enteritis mortality syndrome by restricting feed intake and 2) to develop a drinking water supplement that supports the immune functions of poults with inanition. Poults were restricted to 14 g of feed/d for 7 d beginning at 14 d of age then fed ad libitum until 36 d (recovery). The control was fed ad libitum. During the feed-restriction period, duplicate groups of 6 poults received 1 of 5 drinking water treatments: 1) restricted feed, unsupplemented water; 2) restricted feed + electrolytes (RE); 3) RE + glucose + citric acid (REGC); 4) REGC + betaine (REGCB); or 5) REGCB + zinc-methionine (REGCBZ). Immunological functions were assessed by inoculating poults with SRBC and B. abortus (BA) antigen at 15, 22, and 29 d of age. Antibody (Ab) titers were determined 7 d later for primary, secondary, and recovery responses. The primary and secondary total Ab titers to SRBC for restricted feed were 4.71 and 6.16 log3, which where lower (P < 0.05) than for controls (8.00 and 9.66 log3) and the other treatments. The recovery Ab titer for controls was 10.7, significantly higher than restricted feed (8.71) and RE (8.10) groups but not different from other treatments. The primary total Ab responses to BA were significantly lower in the restricted feed and RE groups as compared with the control and other treatments. Although feed restriction of poults to maintenance reduces the humoral immune responses, these responses can be significantly improved by drinking water containing electrolytes and especially sources of energy such as glucose and citric acid.

Growth and Digestive Function of Turkeys Surviving the Poult Enteritis And Mortality Syndrome

Abstract Stunted growth of poults afflicted by enteritis mortality syndrome (PEMS) may be associated with depressed digestive capabilities. We conducted two experiments to test this hypothesis. Survivors of PEMS were obtained from a research flock that had been purposefully infected at 5 d of age with PEMS inoculum that included turkey corona virus. The PEMS survivors were assigned to Experiments 1 and 2, beginning at 40 and 35 d of age, respectively. Three groups (large, L; medium, M; and small, S) and two groups (L and S) of 20 poults each were selected to represent different degrees of stunting in Experiments 1 and 2, respectively. When the body weights of each group in both experiments were plotted using initial body weight as the starting point, all of the weights fell on the normal growth curve except Group S in Experiment 1. Therefore, there was no evidence of compensatory growth over the period studied. In Experiment 1, apparent fat absorption (AFA) was significantly higher (P < 0.05) for control (85.9%) than for M (78.5%) and S (78.3%) groups, and AME, for the control group was significantly higher than all the PEMS-survivor groups. In Experiment 2, Group L had a higher AFA and AMEn than Group S. AFA and AMEn improved in both groups over time. The digestive capabilities of PEMS survivors were depressed proportionally to the degree of stunting. Impaired fat digestibility and dietary energy utilization in PEMS-afflicted birds are likely contributors to stunted growth and reduced recovery rates.