Agriculture Reference
In-Depth Information
where CI is individual colostrum intake (g), t is time (min) elapsed between the 1
st
and 2
nd
weighing (which defines 'duration of colostrum intake'), BW24 is body weight at 24 h (kg),
BWB is birth weight (kg), and t
FS
is the interval between birth and first suckling (min).
The prediction equation by Devillers
et al.
(2004) was established using bottle-fed piglets.
However, the predicted colostrum intake of piglets, and hence colostrum yield of sows,
seems to be underestimated and the reason is likely that bottle-fed piglets have a much
lower physical activity than sow-reared piglets. An alternative method to quantify
colostrum intake of piglets, and hence colostrum yield of sows, is the deuterated water
(DO) dilution technique, whereby the water intake from colostrum is quantified using
DO. An initial blood sample (background) is collected from piglets immediately after birth
and deuterated water is then injected i.m. in the piglets. Enriched piglets are provided no
access to suckle colostrum for 1 h, at which time a second blood sample is collected and
piglets are then allowed to suckle colostrum. Then, 24 h after the 1
st
piglet was born, a
third blood sample is collected from each piglet and all blood samples are analysed for
content of DO. The dilution of DO between the second and third blood samples is used to
quantify the water intake from colostrum, and chemical analyses of collected colostrum
are used to convert colostrum water intake into colostrum intake. The technique is rather
accurate but quite expensive, and it requires a lot of labour and hence is not applicable in
most studies focusing on colostrum production. In a recent study (Theil
et al.
, 2014a), it
was found that colostrum intake quantified by the DO dilution technique was 43% higher
than that predicted by the equation proposed by Devillers
et al.
(2004).
8.3.3
Factors affecting colostrum yield
Regardless of the method used to estimate colostrum yield, the total yield of colostrum
secreted for 24 h is highly variable among sows. When quantified according to the
prediction equation proposed by Devillers
et al.
(2007), it averages 3.3 to 3.7 kg but
individual yields range from 1 to more than 6.0 kg (Devillers
et al.
, 2007; Quesnel, 2011).
Despite an increasing interest on colostrum production during the past decade, few
studies have provided knowledge on colostrum yield and its influencing factors. Thus,
this review will also refer to studies which described factors that might affect litter growth
in early lactation. Indeed, litter growth from birth to day 3, 5 or 7 of lactation is related
with consumption of colostrum during the 24 h after birth.
Sow vs. piglets
It is well known that sow milk production is stimulated by stimuli originating from
suckling piglets and thus depends on litter size and weight. The influence of the
litter, however, seems to be far less important during the colostral period. This was
demonstrated firstly by the fact that piglets which were bottle-fed with colostrum during
the first 24 h after birth had a voluntary intake exceeding 450 g/kg birth weight, which
was twice the average consumption of sow-reared piglets (Devillers
et al.,
2004). This
result suggests that sows normally produce less colostrum than could be consumed by the
litter. Secondly, colostrum is freely available during the first hours after parturition (De
Passillé and Rushen, 1989) and regular suckling by piglets to maintain lacteal secretions
