Effects of dietary Original XPC on selected blood variables in layer pullets challenged with Mycoplasma gallisepticum,.

Effects of dietary Original XPC (XPC) on 17 selected blood variables in commercial layer pullets challenged with the virulent, low-passage R strain of Mycoplasma gallisepticum (RlowMG) were investigated. Hy-Line W-36 pullets sourced from M. gallisepticum-clean layer breeders were fed a basal diet with XPC (1.25 kg/metric ton) or without from hatch until 12 wk of age (woa). At 8 and 10 woa, half of the birds in each dietary treatment were challenged with RlowMG. Blood samples were taken immediately before the initial RlowMG challenge at 8 woa and again at 12 woa (4 wk after challenge). At 8 woa, blood pH was lower and glucose concentration was higher in the preassigned challenge treatment groups. At 12 woa, the concentration of oxygen dissolved in the blood was significantly lower in the RlowMG-challenged group than the unchallenged group of birds regardless of dietary treatment. The RlowMG challenge significantly increased blood carbon dioxide partial pressure, calcium, sodium, anion gap, osmolality, glucose, and corticosterone levels but significantly decreased blood oxygen partial pressure, oxyhemoglobin concentration, concentration of oxygen dissolved in the blood, chloride, and pH levels. Because blood pH and glucose concentration at 8 woa were examined before challenge, their baseline values were biased with respect to challenge treatment before treatment was applied. However, the lack of a significant main effect due to diet at 8 woa for blood pH and glucose concentration, along with the other 15 blood variables, indicate that the baseline data with respect to dietary treatment were unbiased, allowing for real dietary effects to be accurately assessed. In conclusion, layer pullets challenged with RlowMG undergo a stress response associated with changes in various physiological blood variables, and a decrease in pH and increase in carbon dioxide partial pressure, in association with a lack of change in bicarbonate, indicates that the stress response caused by the RlowMG challenge was associated with respiratory acidosis. Nevertheless, feeding XPC did not influence the effects of challenge treatment on these postchallenge physiological blood values.

Utilizing original XPC™ in feed to reduce stress susceptibility of broilers.

Reduction of stress is an important factor in improving poultry welfare, especially during periods of heat stress. A study was conducted to evaluate the effects of feeding the functional metabolites of Diamond V Original XPCTM to broilers reared under ambient or heat stress temperatures. Dietary treatments included: control feed (CON) and Original XPC fed continuously at 1.25 kg/MT (XPC). Half the birds in each dietary treatment were subjected to either no heat stress (24°C constant) or heat stress (35°C:24°C for 18:6 h daily) from 28 to 42 d. At the end of the heat stress period, blood was collected from 40 birds/treatment. Blood was analyzed for plasma corticosterone (CORT), plasma HSP70 (HSP70), and heterophil/lymphocyte ratios (H/L). At 42 d, bilateral metatarsal traits were also measured in 40 birds/treatment to assess physical asymmetry. Birds fed XPC had significantly lower CORT levels than CON (P < 0.001; 5,129 ± 617 vs. 8,433 ± 730, respectively). Physical asymmetry scores were also significantly higher in CON compared to XPC fed broilers (P < 0.001; 1.50 ± 0.13 vs. 0.54 ± 0.05, respectively). H/L ratios were significantly greater in CON than for XPC birds (P = 0.01; 0.81 ± 0.05 mm vs. 0.62 ± 0.05 mm, respectively). No differences were observed between CON and XPC fed broilers in HSP70. However, heat stress did increase (P < 0.0001) HSP70 compared to no heat stress birds (5.65 ± 0.12 vs. 4.78 ± 0.11 pg/mL, for heat stress and no heat stress, respectively). Feeding XPC to broiler chickens improved animal welfare via reduced stress indicators while under heat stress or no heat stress conditions. These results indicate that feeding XPC may improve poultry welfare by reducing heat stress susceptibility.

Effects of feeding Original XPC™ to broilers with a live coccidiosis-vaccine under industry conditions: Part 1. Growth performance and Salmonella inhibition.

Supplementation of poultry diets with Diamond V Original XPC™ (XPC) has been proposed as a means to ameliorate the commonly observed loss of appetite and depression of growth in birds given a live coccidiosis vaccine. A study was conducted to compare the effects on bird performance of a live coccidiosis vaccine in broilers, with and without the dietary inclusion of XPC (1.25 g/kg). Ross 708 male broilers (n = 1,280) were allocated to one of 4 feed treatments: cocci-vaccine (T1), cocci-vaccine + XPC (T2), cocci-vaccine + salinomycin in the grower diet only, (T3), and cocci-vaccine + salinomycin in the grower diet + XPC (T4). Birds consuming diets containing XPC (T2 and T4) and salinomycin (T3) exhibited increased (P < 0.05) feed intake and significantly heavier body weights at 28 d (1.70, 1.74, and 1.67 kg, respectively) and 42 d (3.29, 3.31, and 3.26 kg, respectively). Feed conversion ratio at 28 d was improved (P < 0.05) by adding XPC to diets (T2: 1.47 and T4: 1.44) compared to control diets (T1: 1.50 and T3: 1.47). Salmonella prevalence determined via selective media indicated the inclusion of XPC in the diet resulted in a significant reduction of Salmonella when compared to treatments lacking XPC. Molecular confirmation of Salmonella species indicated S. Kentucky to be present in 38 of the 39 positive samples. Results revealed the ability of XPC in reducing the prevalence of Salmonella. Results from this study also suggest that XPC could be used in conjunction with a live coccidiosis-vaccine to increase growth rate and improve feed conversion of broilers. However, further work is needed to delineate more specific effects directly attributable to XPC.