Further studies on unrestricted whey for fattening pigs including the effect of omitting antibiotic from the diet during the later stages of fattening

Abstract

1. Results are reported of an experiment with fattening pigs carried out under commercial conditions, to obtain further information on the comparison of all-meal feeding with meal plus unrestricted amounts of whey. In addition, the effect of omitting the antibiotic, oxytetracycline, from the diet during the latter half of the fattening period was investigated.2. There were four treatments. (i) Meal only ad lib. up to a daily maximum of 6 lb./pig, with oxytetracycline included in the diet for the whole fattening period. (ii) As (i) but oxytetracycline included in the diet only up to an average pen live weight of 130 lb. (iii) 3 lb. meal reduced to 2 lb./pig/day by 13 weeks of age plus unrestricted amounts of whey with oxytetracycline included in the basal meal for the whole fattening period. (iv) As (iii) but oxytetracycline included in the diet only up to an average pen live weight of 130 lb.There were five pens of nine group-fed pigs on each treatment, involving a total of 180 pigs. The pigs were on experiment from approximately 8 weeks of age to bacon weight. Comprehensive carcass measurements were made on all pigs.3. The meal plus whey-fed pigs grew significantly slower and utilized their food significantly less efficiently than those fed meal only. They also had a significantly lower dressing percentage, but longer and less fat carcasses than the all-meal fed animals. The results are discussed in relation to those obtained in earlier experiments completed under similar conditions at the Cow and Gate farm.4. Comparison of the efficiency of food utilization results of the all-meal and meal plus whey-fed pigs showed that 1 gal. of whey replaced approximately 0·7 lb. of meal.5. The results showed that omission of antibiotic from the diet of either the all-meal or meal plus whey-fed pigs after they reached 130 lb. live weight, had no significant effect on growth rate, efficiency of food utilization or any carcass measurements of the pigs.We wish to thank the Director of Messrs C. and G. Prideaux, Ltd., Bacon Curers, Motcombe, Shaftesbury, Dorset, for permission to take carcass measurements of the experimental pigs, and we are greatly indebted to Messrs K. Lawrence and P. Prideaux who most conscientiously took these measurements.

A comparison of dried skim-milk and white fish meal as protein supplements for fattening pigs: IV. Further studies with pigs fed unrestricted amounts of whey under commercial conditions

“…The age at which the pigs reached their peak average daily consumption of whey, namely during about the 21st-23rd weeks of life, agrees approximately with the results of the first of two trials published in 1957 (5), but is some 4-5 weeks earlier than in the second of these two trials and in two other whey-feeding trials subsequently reported (1,4).…”

“…The earlier trial was made during the summer months, whereas the present experiment was in progress mainly during the early winter months; evidence of seasonal effects on whey consumption will be discussed later. Further, continuous breed improvement work is in progress in the Cow and Gate herd of pigs, and it is probable, for example, that the improvement in performance of the experimental pigs since trials were first made on the Cow and Gate farm observed by Braude et al (4) was at least in part a reflexion of this breeding work. One can speculate that changes in nutritive requirements for optimal performance may have occurred as this work on breed improvement progressed.…”

“…Pigs. Details of the pigs used, their pre-experimental management, breeds, selection for experiment and housing, were all identical with those in the trial reported by Braude, Mitchell, Cray, Franke & Sedgwick (4). There were five pens of nine pigs on each of the four treatments, making a total of 180 pigs for the experiment.…”

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

“…This was based on the observation made in previous trials that the rate of growth of pigs given 2 lb meal/day with unrestricted whey either declined as they got older (Braude et at. 1957;Braude, Mitchell, Cray, Franke & Sedgwick, 1958) or increased only very slightly (Braude, Mitchell, Cray, Franke & Sedgwick, 1959a;Braude et at. 19596).…”

“…Subsequent experiments using this system of feeding (Braude, Mitchell, Cray, Franke & Sedgwick, 19596), showed that either 10% white fish meal or 15% dried skim-milk should be considered the minimum amount of these protein supplements that should be included in the basal meal fed with unrestricted whey. It was shown also that reduction of the daily meal allowance to 1 lb or less had a marked adverse effect on the growth rate of the pigs.…”