Gilt feeding – Ad libitum feeding

Optimum feeding of gilts by ad libitum feeding

 

Figure 1 Feed curve ensuring ensure a balance of the feed amount in relation to age and weight.

 

 

Find P2 about 7 cm from the backbone. When measured in a straight line from the tip of the last up towards the backbone

 

Gilts represent the future production of the sow herd, and DanBred gilts come with an extraordinary genetic potential for reproductive performance.

Careful attention to the feeding of the DanBred gilt will be rewarded in the farrowing unit- setting a prime starting point on the road to release the genetic capability for optimum lifetime performance.

The recommended feed curve will ensure a balance of the feed amount in relation to the age and weight of the gilts as shown in figure 1 (on the left).

 

 

The huge potential for growth in the DanBred animals means that there must be a focus to limit the growth rate in the DanBred gilts, which is why the feed energy level is a very important factor when working with DanBred gilts.

The optimum lifetime production for DanBred gilts is reached when the gilt is mated for the first time in the second heat, at the age of 230-250 days weighing between 140-160 kg with a back-fat thickness of 14-15mm at the P2 measuring point (2).

Moderation of gilt growth

Age, Days (weeks) Weight, Kg ADG, g/day
28 (4) 7 250
56 (8) 17 430
70 (10) 25 430
84 (12) 30 500
112 (16) 48 500
140 (20) 71 500
168 (24) 96 570
196 (28) 121 615
224 (32) 143 640
245 (35) 160 650
From
56 to 135 days
145 770
Table 1: Optimum ADG from weaning to first mating.

The feeding strategy for DanBred gilts is set to meet nutrient requirements as well as maximisation of long-term productivity.

A daily gain of 750-800 g/day from 30 kg to 140 kg will lead to the best possible basis for long-term reproduction productivity in DanBred gilts [2].

 

Figure 2 Feed to ensure balanced steady growth

 

Feeding of DanBred gilts should ensure a steady continuous but controlled weight gain throughout the period of growth. Expected weight development from following the DanBred recommendations is shown in figure 2.

 

The target is to initiate puberty and the onset of the oestrus cycle, support the pre-pubertal mammary development and maximise the productivity of litter size and longevity.

Studies indicate that the age of the gilt, as well as the correct introduction of boar contact, are the main factors when it comes to the onset of puberty [2][3].

The amount of body fat in the gilts might help the onset of puberty in gilts [1].

The managed growth rate for replacement gilts has shown to positively correlate with sow longevity because the moderated growth rate has a positive effect on bone growth giving the gilts stronger legs and thereby increasing longevity in breeding animals [5].

In a 2004 trial, Vestergaard et. al. found that 50 to 60 % of sows were culled due to leg problems and this can be related to unmanaged growth rates during gilt development.  Managing growth and increasing fat deposit through feeding will give lighter but slightly fatter gilts at the age of first mating.

 

Gilt body fat content can play a role in the onset of puberty, therefore, it is important to ensure a back fat target of 15 mm  (or at least 14 mm) at first mating.

Mammary development in the replacement gilts is not affected by the more linear growth curve, as the vast part of the udder, growth happens in the last third of gestation [2].

Size of first litter might be marginally decreased at steady growth rate, but flushing the gilts before mating has proven to be a very efficient way of increasing the ovulation rate at mating in the second oestrus and thereby enlarge the litter size [1].