Reproductive management in pigs: emphasis on the different roles of the boar and on optimal insemination management

Boars have different roles in the reproductive management in pigs. Boar contact can stimulate follicle development and thereby induce oestrus, both in gilts and sows. Boar contact during oestrus is essential for good oestrus expression, which is essential for the correct timing of insemination and the proper use of boar contact during insemination can stimulate sperm transport and thereby fertilisation. Stimulation by boars clearly has an olfactory component (the boar smell), but can also have an auditory, visual and evn tactile component. The background of the different roles and some of these different components of the boar are discussed. To enable a good farrowing rate and litter size, sows should be inseminated between 0 and 24h before ovulation. However, it is not possible to accurately predict the time of ovulation in sows. Although ovulation takes place at a relatively fixed 60-75% of the duration of oestrus, the duration of oestrus varies considerably between sows and between farms, resulting in a variable ovulation time from onset of oestrus. Therefore, most farmers inseminate their sows every day of oestrus to ensure insemination within the optimal period. Since post-ovulation inseminations should be avoided, it is adviced to only inseminate sows while they still show an optimal standing respons

Effecten van eenvoudige koolhydraten en fermenteerbare koolhydraten op de binnentoom variatie bij varkens

2 proeven werden uitgevoerd. Het doel van de 1e was nader inzicht te krijgen in het mechanisme dat ten grondslag ligt aan de relatie tussen insuline-stimulerend voer (dextrose+lactose) tijdens het interval spenenovulatie, follikelontwikkeling in de laatste dagen voor inseminatie en (variatie in) ontwikkeling van embryo's tijdens de vroege dracht. Het doel van de 2e proef was om nader inzicht te krijgen in de directe effecten van de specifieke voercomponenten dextrose, lactose, sucrose en suikerbietenpulp (zowel apart als gecombineerd) op glucose, insuline en IGF-1 profielen in zeugen om zo diëten te vinden met de hoogste potentie om insuline en IGF-1 afgifte te stimuleren

Effects of loose housing and the provision of alternative nesting material on peri-partum sow behaviour and piglet survival

Sows are strongly motivated to perform nestbuilding behaviour before parturition. This behaviour is often restricted in commercial systems due to confinement of the sow and lack of suitable nesting material to be used on slatted floors. This study aimed to investigate effects of loose vs. crated housing and the provision of alternative nesting material on periparturient sow behaviour and piglet survival. In a 2 × 2 arrangement, sixty-eight sows were assigned to either loose housing or crates and were either or not provided with nesting material consisting of jute sacks and straw balls. All sows had a rope. Postures and manipulation of materials and pen were observed using 5 min scan sampling for the 12 h before and the 24 h after parturition. Behaviour during parturition was scored continuously and included nose-nose contact between sow and piglets and crushing incidences. No interactions between treatments were found. In the 12 h prepartum, loose housed sows showed less sitting (5 vs. 9%) and ventral lying (29 vs. 38%) and more lateral lying (33 vs. 23%) and floor manipulation (10 vs. 5%) than crated sows. During parturition, loose housed sows spent less time sitting (2 vs. 6%), had fewer postural changes (34 vs. 50), showed less fence manipulation (0.1 vs. 2%) and had more nose contact with piglets (56 vs. 19 times). Provision of nesting material increased pre-partum lying (63 vs. 57%), increased manipulation of materials (14 vs. 8%) and reduced manipulation of floor (5 vs. 10%) and fence (5 vs. 9%). During parturition, sows with nesting material showed less standing (6 vs. 10%) and more lying (90 vs. 84%). No effects were found on behaviour in the 24 h after parturition or on parturition duration (3.3 ± 0.1 h). During parturition, the times lying down and the number of piglets that died by crushing tended to be lower with provision of nesting material (0.1 vs. 0.3). In the 48 h after parturition, loose housed sows crushed more piglets. In conclusion, both loose housing and the provision of alternative nesting materials affected prepartum sow behaviour and resulted in less activity during parturition, with some tendencies for beneficial effects on (near-) crushing of piglets during this period. Thus, both loose housing and the provision of alternative nesting materials, likely particularly the jute sacks, have a beneficial effect on periparturient sow behaviour

Groepshuisvesting van zeugen tijdens de vroege dracht = Group housing of sows during early gestation

This study investigated what the success factors and risk factors are for group housing for sows within 4 days post-insemination. We concluded that with each system of group housing good reproduction results and adequate welfare of the sows can be achieved at introducing the sows into the group within 4 days post-insemination. An animal-directed approach (i.e., attention for the individual animal’s needs), attention for farm management and farm optimisation, in other words, the farmer’s management, and an adequate rearing of gilts are important success factor

The second litter syndrome in sows; causes, consequences and possibilities of prevention

Second parity sows may have suboptimal farrowing rate and litter size, resulting from relatively high weight losses during first lactation. Sows with low performance in second parity on average also have a lower performance in later parities and increased chances of early culling. To overcome this reduced second parity reproductive performance, feed intake during first lactation needs to be improved. To realise this, both pre-farrowing and lactational –nutritional- management needs to be optimised. On the other hand, also post-weaning management strategies can influence second parity performance. Improved follicle recovery prior to insemination can be achieved by applying either skip-a-heat, or daily altrenogest treatments. These both postpone insemination time after oestrus, resulting in improved performance