This thesis compares growth and behaviour of domestic sows and piglets in confined pens versus get-away pens (where sows could leave their fitters at will), to ask whether parent-offspring conflict occurs, whether it increases with offspring age, whether it involves offspring access to the udder, and whether it affects animal production or welfare. Parent-offspring conflict occurs in domestic pigs: piglets of Confined sows suckled more and ate less solid food but grew at the same rate as piglets from Get-away sows, indicating they obtained more milk. Confined sows lost more weight than Get-away sows and returned to oestrus later, indicating a fitness cost of providing the additional milk. Parent-offspring conflict increased with piglet age: as the fitter aged, Get-away sows spent more time away from their young and the differences between Get-away sows and Confined sows in weight loss and nursing frequency increased. In Get-away sows, the reduction in contact with their young occurred rapidly, but its timing varied greatly among individual sows. Behavioural conflict over access to the udder is a plausible mechanism by which conflict is expressed in swine: piglets from Confined pens spent more time nuzzling the udder than piglets of Get-away sows. Piglets from Get-away sows nuzzled the udder a higher proportion of the time when the sow was present than piglets from Confined sows. Get-away sows terminated more nursings than Confined sows thus limiting the amount of contact piglets had with the udder after nursing. Mowing sows to control maternal provisioning improved productivity: there was a slight benefit of reduced time to the next oestrus for Get-away sows. Piglets from Get-away sows gained more weight and consumed more food after weaning than piglets from Confined sows. There was only slight evidence that get-away pens reduced behavioural indicators of post-weaning stress (e.g., movements, vocalizations, response to playback of vocalizations) for either the pi

Buvo nustatinėjami paršavedžių folikulų įvairių stadijų dydžiai. / Determined in sows of different stages of follicle sizes.

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2008. / Härtill 4 uppsatser.

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2003. / Härtill 4 uppsatser.

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2003. / Härtill 3 uppsatser.

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2005. / Härtill 4 uppsatser.

Thesis (M.S.)--University of Missouri-Columbia, 2007. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on April 9, 2009) Vita. Includes bibliographical references.

Thesis (Ph. D.)--Michigan State University. Dept. of Animal Science, 2008. / Title from PDF t.p. (viewed on July 23, 2009) Includes bibliographical references. Also issued in print.

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1993. / Vita. Abstract. Includes bibliographical references (leaves 64-77). Also available via the Internet.

The work deals with the analysis of some conditions to increase the level of piglets in factory farms. In addition to the genetic material used in crossing the farm, there is really important material support: good nutrition, breeding environment and nursing care. All these requirements were fullfilled in evaulated plant. In the breeding herd, were revealed a significant effect of early estrus and early pregnancy rate in the interval weaning of piglets. The obtained data showed that the percentage is not significantly different farrowing in sows and gilts. The number of live born piglets is no significant difference in sows and gilts. That's why is advantagous to continuously include gilts in basic herd and early replacement of saws according to their health status and number of past litters. Return breeding of sows should be at the annual breeding 23 to 25 piglets per sow.