Grouping of animals
Twenty-two buffaloes in the advanced stage of pregnancy (-30 days) were selected and grouped into three equal groups based on their most probable producing ability (MPPA) for milk (average 2184.58 kg), parity (average 2.27) and body weights (average 589.22 kg). Eight buffaloes were assigned to control, while seven each in two treatment groups,
i.e. T
1 and T
2.
Chemical composition of feeds
The chemical composition of representative feed samples collected during the experimental period indicated that the feed was capable to fulfill the nutrient requirements (ICAR, 2013) of buffaloes. Concentrate mixture, wheat straw and green berseem had 19.21%, 3.08% and 16.19% crude protein and 56.25%, 44.79% and 47.9% nitrogen-free extract, respectively.
Variation in colostrum composition
The colostrum composition is highly variable and is affected by factors like the breed of buffalo, parity, pre-partum and dry period nutrition and also the length of the dry period. The day-wise variation in colostrum composition due to supplementation of vitamin A and E in Murrah buffaloes is represented in Table 2.
Colostrum fat
No significant (P>0.05) variation was observed on colostrum fat % due to treatment effect (Table 2), though values were high in treatment groups and were up to the tune of about 20% or higher as compared to control group on the day just after parturition.
Mutoni et al., (2012) also reported improvement in colostrum fat (4.88% vs. 5.05%, P>0.05) percentage due to supplementation of vitamin E in Sahiwal cows as compared to the un-supplemented group. Similar to present findings De
Ondarza et al., (2009) also reported improvement in milk fat % due to supplementation of beta carotene especially in early lactation cows and mature cows. Lotthammer (1979) in his studies concluded that β-carotene deficiency was related to a lower milk fat percentage in dairy cattle. Improvement in milk fat percentage in response to β-carotene supplementation may be due to higher rumen cellulolytic bacteria, as seen in an
in-vitro study by
Hino et al., (1993). Another possible mode of action could be that supplemental β-carotene altered rumen bio-hydrogenation and reduced the formation of trans-10 isomers in the rumen, resulting in less milk fat depression, as vitamin E has been shown to do
(Bell et al., 2006; Pottier
et al. 2006).
Over the period of time
i.e. day 1 to 5, a reduction was apparent in the fat percentage of colostrum in all three groups, though significant reduction (P<0.05) was observed only in control and T1 groups (Table 2).
Kehoe et al., (2007), Abd
El-Fattah et al., (2012) and
Morrill et al., (2012) also showed that all components of colostrum except lactose decreased gradually with the advancement of the period after calving.
Colostrum protein
Improved protein % was observed in colostrum of buffaloes of both the treatment groups, during the first three days of the collection as compared to buffaloes of the control group, though the values were significant (P<0.05) in group T2 only. Similar to present observation
Mutoni et al., (2012) also reported an improvement in colostrum protein (4.27% vs. 4.35%, P>0.05) percentage due to supplementation of vitamin E in Sahiwal cows as compared to control group. Likewise,
Oliveira et al., (2015) reported an increase in milk protein content from 2.90 to 2.96% when supplemented beta carotene @ 1.2 gram/day/cow for 14 days pre-partum.
Nieto et al., (2015) also reported that Colostrum protein concentration was affected by supplementation of vitamin E in Ewes (14.3% vs. 17.3%, P<0.05).
Reducing tendency was also visible in colostrum protein % with the advancement of days after calving in all three groups, though non-significant. Previous workers (Georgiev and Penchev, 2005;
Kehoe et al., 2007; Patto et al., 2016) also reported reduced protein % of colostrum with the advancement of days after parturition.
Colostrum lactose
A significant (P<0.05) improvement was observed in colostrum lactose % on day 3
rd in the T1 group as compared to the other two groups. In a study,
Mutoni et al., (2012) reported an improvement in colostrum lactose (3.12% vs. 4.37%, P<0.05) percentage due to supplementation of vitamin E in Sahiwal cows as compared to control group.
Nieto et al., (2015) interpreted that lactose synthesis regulates the amount of colostrum and thus had a significant role to play.
No significant (P>0.05) variation was observed in lactose % with the advancement of days after parturition in all three groups but an inclining pattern was being almost followed over the period of time. Likewise,
Kehoe et al., (2007), Abd El
-Fattah et al., (2012) and
Morrill et al., (2012) also showed that lactose content gets increased gradually with the advancement of the period after calving.
Colostrum solid-not-fat
A significant (P<0.05) improvement was observed in colostrum solid-not-fat % at day 3
rd in group T1 as compared to T2 and control groups. No significant (P>0.05) variation was also observed in solid-not-fat% over a period of time after parturition, though a numerical reduction was reported in values due to the advancement of days after parturition.
Kehoe et al., (2007), Abd
El-Fattah et al., (2012) and
Morrill et al., (2012) also reported a declining trend in most of the colostrum constituents with the advancement of days in milk except lactose.
Colostrum total solids
Total solids of colostrum in buffaloes of treated groups were significantly high (P<0.05) during the first two days of study though the values were numerically high throughout the collection period over the values of the control group. Similar to present observation
Capper et al., (2006) observed improvement in the quality of colostrum due to vitamin E in late pregnancy.
Oldham et al., (1991) also observed a trend for increased milk yield when cows were supplemented with β-carotene from -75 d prepartum to 42 d postpartum. These results suggest that to elicit a positive milk yield response to β-carotene, the supplementation may need to occur in early lactation.
A significant (P<0.05) reduction was apparent in total solids values of group T1 over a period of time, while the effect was non-significant (P=0.129) in group T2. Previous workers
(Kehoe et al., 2007; Abd El
-Fattah et al., 2012 and
Morrill et al., 2012) also concluded regarding a similar trend in most of the components of colostrum.