Dietary Whey Supplementation in Experimental Models of Wound Healing

Whey is a dairy product containing milk serum proteins with diverse biological effects. In this study, the effect of dietary whey supplementation on wound healing was investigated. Rats were fed a standard or whey-supplemented diet for three weeks. Wound healing parameters, glutathione, and lipid peroxide levels were determined three days after the application of two different models of wound healing, i.e. laparotomy and colonic anastomosis. Dietary whey supplementation significantly increased glutathione levels and suppressed lipid peroxidation after experimental laparotomy and colonic anastomosis. Bursting pressures, hydroxyproline, and cytokine levels were not changed. Our results show that dietary whey supplementation increases glutathione synthesis and cellular antioxidant defense. Long-term effects of whey feeding on wound healing remains to be investigated.

EVALUATION OF CONCENTRATED WHEY AND CANOLA MEAL MIXTURE AS A SUBSTITUTE FOR GRAIN IN THE RATIONS OF CALVES

Twenty-four male Holstein calves averaging 117 kg body weight were each randomly assigned to one of four treatments: I, grain mixture, 2.0 kg·animal−1∙day−1; II, evaporated whey-canola meal mixture (EWC), 1.0 kg∙animal−1∙day−1; III, EWC, 2.0 kg·animal−1∙day−1; and IV, EWC, 4.0 kg∙animal−1∙day−1. All four groups were fed hay free choice. The effect of level of whey feeding on body weight gain, rumen fermentation and plasma minerals was then measured over a period of 120 days. The intake of EWC dry matter (DM) was 17.2, 34.4 and 55.5% of total DM intake for treatments II, III and IV, respectively, while the grain mixture represented 42.8% of DM intake for treatment I. Body weight gain during the 4-mo feeding period averaged 1.00, 0.93, 1.00 and 1.12 kg/day for treatments I–IV, respectively. Level of whey feeding had a marked influence on rumen fermentation. The molar proportion of rumen acetate was significantly lower and that of butyrate and valerate were significantly higher for treatments II and IV compared with treatments I and II. The effect of level of whey feeding on blood metabolites was less consistent although there was a trend towards a lower hematocrit and blood urea nitrogen levels with the highest level of whey feeding. The results of this trial indicated that the feeding of the EWC product at 2.0 and 4.0 kg/day caused a marked change in rumen fermentation but was a suitable source of energy for growing calves fed hay. Key words: Whey, utilization, dairy calves, rumen volatile acids

THE CONSUMPTION OF ACID WHEY BY LACTATING COWS

Acid whey with 0.1% formalin added as a preservative was fed free choice for 14 days to four lactating Holsteins. Whey intake averaged 55 kg/cow/day (3.6 kg of whey dry matter (DM)). Intake of corn silage decreased from 7.1 to 3.9 DM/day and intake of hay was stimulated slightly. Milk yield was sustained and milk protein content increased during the whey-feeding period.

The effect on the performance of growing pigs of the level of meal fed in conjunction with an unrestricted supply of whey

SummaryResults are reported of an experiment made under commercial conditions on the effect of the level of meal fed in conjunction with an unrestricted supply of whey on the performance and carcass quality of pigs.All the pigs received the same meal mixture and had continuous access to an unrestricted supply of whey. The four treatments were: (1) 3 lb meal per pig per day reduced to 2 lb at 13 weeks of age; (2) 3 lb meal per pig per day throughout; (3) 2½ lb meal per pig per day throughout; and (4) as (1) but the daily allowance of meal increased to 2½ lb/pig at 20 weeks of age. There were five pens of nine group-fed pigs on each treatment, involving a total of 180 pigs. The pigs were on experiment from 8–9 weeks of age to bacon weight. Comprehensive carcass measurements were made on all the pigs.Mean differences in rate of growth, efficiency of food utilization and carcass quality between the four groups of pigs were small and were not statistically significant. The significant differences in the proportions of meal and of whey consumed by the pigs on the different treatments during the growing period are discussed in relation to relative prices of the two foods. It is concluded that where unrestricted whey feeding is to be used, the feeding system employed in treatment 3 could be recommended in most of the environmental and economic situations likely to be encountered in practice.The superior performance of the pigs in the experiment compared with that in earlier trials is discussed in relation to the stock improvement work and concurrent improvements in housing and management carried out during the intervening years on the Cow and Gate farm in Dorset where the experiments were conducted.