ALBERT

Description: 1. An individual feeding experiment using forty-eight pigs and a group feeding experiment using twenty-nine pigs have been carried out with the object of testing the so-called Lehmann system of pig feeding, where the amount of meal allowed for the fattening pig is restricted to a basal ration of 2½ lb. each and farm bulky foods or food wastes fed ad lib. used as supplementary foods.2. Using a mixture of 6 parts mangold and 1 part biscuit waste as a supplementary food, live-weight gains only slightly less than with all-meal feeding have been obtained and a great saving in meal consumption effected. Under more favourable conditions as much as 1¾ lb. of meal has been saved for each 1 lb. live-weight gain.

Description: 1. The results of two trials involving twenty-four pigs did not provide a clue to the observed craving of pigs for metallic copper.2. There seems to be no advantage in supplementing a normal diet for fattening pigs which contains about 5 p.p.m. of copper with copper given in form of a solution of copper sulphate. The addition of a mixture of copper sulphate, manganese sulphate and iron pyrophosphate to the same normal diet had also no effect on the rate of growth of the pigs and their food consumption.3. The haemoglobin and copper contents of the blood appeared to be unaffected by the addition of copper to the diet. The copper content of the livers showed a tendency to be higher in the livers of the pigs receiving the copper supplements.

Description: Seven experiments are reported in which iodinated casein was fed to pigs. The daily doses varied from 0·25 to 1·5 g. of iodinated casein per pig daily for periods of several weeks. While the higher doses adversely affected the rate of growth of the pigs, the smaller doses were not sufficiently effective to have any practical importance.The thyroid glands of the pigs receiving the iodinated casein appeared to be slightly smaller in size, but their histological picture was not affected.

Description: 1. A survey and. statistical analysis of the records of litters born in the N.I.R.D. herd of Large White pigs over a period of 16 years are presented.2. The mean length of gestation was 114 days for both gilts and sows.3. The mean numbers of pigs born alive and born dead per litter from gilts, 10·0 and 0·2 respectively, were both significantly smaller than the corresponding figures for sows, 11·8 and O·8. No seasonal differences were found.4. The mean total losses of pigs from birth to weaning at 8 weeks were 29·5% of pigs born alive. The losses in litters from gilts, 23·0%, were significantly smaller than in litters from sows, 31·0%. The losses during the winter months both for gilts, 32·5%, and for sows, 35·9%, were significantly higher than during the summer months, 19·4% and 26·7% for gilts and sows respectively.5. Over 50% of the total losses were due to crushing by the dam, 74·1% of the losses from this cause occurring during the first 48 hr. after birth.6. The mean number of pigs weaned per litter was 8·0. The difference between the number weaned per litter from gilts, 7·7, and per litter from number of pigs was weaned per litter from sows during the summer months, 8·7, than during the winter months, 7·4.7. There was no significant difference between the number of male and of female pigs weaned.8. The mean weight at weaning was 29·9 lb., male pigs, 30·3 lb., being significantly heavier than females, 29·51b. Pigs in litters from gilts, 27·81b., were significantly lighter at weaning than those from sows, 30·0 lb., and for both gilts and sows, pigs reared during the summer months, 29·7 and 31·8 lb. respectively, were significantly heavier than those reared during the winter months, 25·9 and 28·2 lb. respectively.

Description: 1. Three experiments are described in which the value of electrically warmed floors for fattening pigs, aged 9 weeks or more at the start of the trials, was determined.2. Under the conditions of the experiments, no benefit was obtained either in live-weight gain or efficiency of food utilization by the provision of artificial floor warming.3. Data relating to the effect on floor surface temperatures of ambient inside temperature, electrical warming, provision of straw and the pigs themselves were presented.

Description: 1. A review of the literature relating to the frequency at which pigs suckle under natural conditions was made. The evidence indicated that the average interval between successive sucklings is approximately 1–1¼ hr.2. A number of sows and their litters were continuously observed for varying periods of time under natural conditions and a similar average interval between sucklings was observed.3. A review of the literature relating to the determination of milk production of sows was made. This showed that the majority of previous workers imposed, during the periods when the litters were being weighed before and after every suckling, a suckling frequency that did not simulate the natural behaviour of the animals. Evidence suggesting that the imposition of such unnatural conditions invalidated the findings, in so far as they might indicate the true milking capacity of the animals, was discussed.4. An experiment to obtain direct evidence on the importance of the suckling interval in relation to the milk obtained by the pigs was carried out. Conclusive evidence was obtained that when suckling was allowed every hour, both the quantity of milk obtained by the litters and their live-weight gain in 24 hr. periods were much greater than was the case when suckling was allowed only every 2½ or 3 hr. In addition, the pigs on the hourly suckling frequency utilized their milk intake more efficiently.5. An experiment was carried out in which an attempt was made to obtain, under natural conditions, a valid estimate of the 56 days' lactation yield of three Large White gilts. The method of weighing the individual pigs before and after suckling was used, and the animals were allowed to suckle every hour.6. The estimated average lactation yield was 768 lb., with a range of from 882 to 655 lb., although it was suggested that the true yield might be some 5–10% higher. The figures obtained in this work were shown to be very much higher than the yields reported by most of the previous workers.7. The nursing and suckling behaviour of the dams and their litters was studied. Observations of significance in relation to the variation in growth of pigs within a litter were made.8. Data were obtained concerning the average amount of milk obtained by individual pigs at a suckling, the total amount ejected at a suckling, the effect of daylight and of darkness on the amount of milk obtained, the relative productivity of the individual mammary glands and the efficiency with which the milk intake was utilized by the individual pigs in the litter.9. A close positive relation between milk intake and live-weight gain during the first 3 weeks of life was found. During the last 5 weeks of lactation, when supplementary food was available, this close relationship was not seen.10. The growth rate of the suckling pig, as related to the supply of food, was discussed. The evidence available suggested that the supply of sow's milk was frequently insufficient to meet the requirements of the pigs for optimum growth.11. The chemical composition of sow's milk in relation to the stage of lactation was studied.

Description: 1. Results are reported from two experiments in a series to determine the optimal amount of meal to be fed in conjunction with unrestricted whey for fattening pigs.2. In both experiments, one carried out during the summer and the other during the winter season, the same four treatments were given. The control pigs received meal ad. lib up to a maximum of 6½ lb./ head daily. Pigs on the other three treatments received whey ad lib., and either 3 lb., or 3 lb. reduced at two different stages to 2 lb. of meal per head daily. There were ten pens of nine pigs on each treatment, involving a total of 360 pigs. Comprehensive carcass measurements were made on all pigs.3. The data obtained showed that satisfactory results could be obtained by feeding a daily allowance of 3 lb./pig of a proprietary sow and weaner meal throughout the fattening period, in conjunction with unrestricted whey. Where the utilization of as much whey and as little meal as possible was required, it was shown that a reduction from 3 to 2 lb. meal/pig/day by the 13th week of life could be made without adverse effects, apart from an increase of approximately 12 days in the time taken to reach bacon weights.4. Carcass grading results of all whey-fed pigs were reasonably satisfactory, but both the carcass grading and general performance of the control animals was not good. Possible reasons for this were discussed.5. Data concerning the pattern of food consumption over 14-day periods throughout the experiments were presented. Pigs given 3 lb. of meal/day throughout, or 3 lb. reduced to 2 lb./day, consumed up to approximately 3¼–3½ or 3¾–4 gal. of whey/day respectively.

Description: 1. Sixty Large White pigs in ten blocks of six litter-mates were individually fed on six different planes of feeding. Three groups were fed according to live weight and according to three different scales, and in the other three groups the pigs were given as much food as they would eat in 30 min. at two feeds daily up to a maximum of 7·0, 6·5 and 6·0 lb./day respectively. All pigs received the same meal mixtures.2. Although the groups being fed according to the various scales took slightly longer to reach bacon weight, they utilized their food more efficiently than the groups fed on the ‘to appetite’ systems. Thus the pigs fed according to the scale shown in Table 1, but up to a daily maximum of 6½ lb. meal/pig, required about 35 lb. less meal to reach bacon weight than those pigs fed ‘to appetite’ up to a maximum of 7 lb. meal/day. The saving in food costs at present-day prices was approximately 10s. per pig.3. The percentages of grade A carcasses were very high in all groups, but there was a marked tendency for the ‘to appetite’ fed groups to have thicker midback and loin fats, the latter being reflected in the poorer commercial grading results.4. The importance of interpreting the results in the light of the influence of the strain of pig, environment and type of diet fed on the question of plane of feeding, was emphasised.