Agriculture Reference
In-Depth Information
feeding level is generally introduced 2 to 4 wk before parturition. This practice is applied
as a simplistic attempt to match the increased requirements for amino acids due to fetal
growth, but it does not take into account that fetal growth rate changes exponentially
during this phase (Noblet et al. , 1985), and that fetuses retain steadily more nitrogen and
lysine. Yet, other farms choose to feed sows the same daily amount throughout the entire
gestation period whereas some farms use a high-fiber diet and allow the sows ad libitum
access to feed in order to keep things manageable. Increasing the dietary fiber level does
indeed reduce the mean energy intake within a herd (Danielsen and Vestergaard, 2001),
however, ad libitum feeding cannot be recommended for gestating sows because it creates
huge variations in body condition over time. The various impacts of feeding high fiber
diets to sows during gestation are described in details in Chapter 5 (Meunier-Salaün and
Bolhuis, 2015).
In late gestation, most sows are fed at or above the energy requirement (Figure 7.3). At
parturition, sows are typically fed a constant level similar to that used immediately prior
to parturition and then, on d 3 postpartum, the feed allowance is increased daily or in
a stepwise fashion in order to account for the increased demands of milk production
(Hansen et al. , 2012b). The appetite of sows seems to be a limiting factor for nutrient
intake when the feed supply is increased in early lactation and therefore it is common to
feed sows well below their energy requirement. Ideally, feed intake should be increased
quite fast to avoid excessive mobilization of body fat and protein, but sow feed intake
often drops if the feed allotment is increased too rapidly in early lactation (Hansen, 2012).
The recommended feeding level seems to be rather comparable in Canada, Denmark,
France, the Netherlands, and the USA. In spite of that, a great variation in feed supply is
seen at different farms and the feeding levels applied to transition sows seem to be based
merely on current beliefs and practical possibilities rather than on nutrient requirements.
Many farmers attempt to restore the body condition of sows during early- and mid-
pregnancy. In contrast, during the transition period, the feeding curves (and even the
dietary recommendations) are identical for all sows irrespective of parity, live weight,
10
8
6
4
2
0
-10
-5
0
5
10
Days relative to parturition
Figure 7.3. Required amount of feed (solid line) and commonly applied feeding curves (dotted and dashed
lines) for sows during the transition period.
Search WWH ::




Custom Search