Studies on milk production of Large White pigs

Abstract

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.

Teat order affects postweaning behaviour in piglets

“…However, between birth and weaning, the piglets that suckled anterior teats gained more weight than the other piglets, confirming results from other studies (FRASER & JONES, 1975;PLUSKE et al, 2007;SKOK et al, 2007;PEDERSEN et al, 2011). This can be attributed to a greater milk intake after birth in piglets that suckle anterior teats, as it has been shown that the anterior mammary glands of the sow tend to produce more milk than the posterior ones (BARBER et al, 1955;SKOK et al, 2007), and there is a correlation between milk intake and growth of piglets until the third week of nursing (BARBER et al, 1955). In contrast, it is unlikely that the greater weight gain of AT piglets is due to differences in feed intake, as this is very low in suckling piglets during their first weeks of life.…”

The milk ejection reflex in the pig

“…In these instances we never observed a milk ejection. One of the most notable deviations from the usual pattern was 'incomplete suckling', which has been defined as apparetly normal suckling which does not lead to milk ejection (Barber, Braude & Mitchell, 1955;Whittemore & Fraser, 1974). Identification of 'incomplete suckling' has so far been based on behavioural observations or by attempts to milk the udder manually.…”

Effect of Rearing Practices on the Water Consumption by Piglets in the First Eight Weeks after Birth

“…Suckled by the sow, piglets developed a rigid nutritional stereotype divided into three to five phases, recurring at about 1-h intervals, soon after birth. They suck milk under active participation of the sow only during one phase lasting merely 13 to 37 s (Barber et al 1955;Gill and Thompson 1956;Whittemore and Frazer 1974;Newberry and Wood-Gush 1985;Holub 1988;Jensen 1988). From 3 to 5 days of age, however, they not only suck water in milk but also drink it from watering installations (Groth 1980) similarly to grown-up pigs.…”

“…Under such rearing practices their total water intake increases from 481 (in the 1st week) to 1729 g. d-l (in the 8th week) (Aumaitre 1964(Aumaitre , 1965. However, the consumption of free water by drinking is lower (Bauer et al 1978;W6jcik et al 1978;Bauer 1983, Fraser et al 1988.…”