Soymilk Replacer versus Whole Milk: Effects on Calf Performance. Australian Dairy Symposium

Abstract

The demand for milk and its importance in human nutrition limits its availability for neonatal dairy calves, especially in regions where the local breeds of dairy cows have low genetic potential for milk production. Calves are prone to stress during the preweaning period (2-3 months) and therefore need adequate nutritional management (Jenkins, 2021). The early life nutrition of calves has a lasting impact on their productivity and fertility throughout their lifespan (Drackley, 1999; Roy et al., 2016). To enhance the survival and health of young pre-ruminants, alternative sources of milk can be provided (Khan et al., 2012; Dairy Australia, 2020). Soymilk is a plant-based alternative to cow's milk that is made from soybeans (Gadzama et al., 2017). It contains protein, fat, carbohydrates, vitamins and minerals, but it also has some anti-nutritional factors (ANFs) that can interfere with the digestion and absorption of nutrients by calves. However, adequate processing can inactivate ANFs in soymilk making it a promising alternative as a milk replacer (Gernah et al., 2013; Gadzama et al., 2017; Dairy Australia, 2020). This study evaluated the effect of substituting a portion of whole milk with soymilk on the preweaning growth performance of dairy calves. We hypothesized that soymilk could partially replace whole milk without compromising the growth performance of preweaning calves. A total of 16 Holstein x Bunaji calves with an average initial live weight of 34.8 ± 0.7 kg (mean ± standard deviation) were randomly assigned to one of four dietary treatments: 1) control, without soymilk; 2) low, with 25% DM soymilk; 3) medium, with 50% DM soymilk; 4) high, with 75% DM soymilk in a completely randomized design. Each calf received 2 litres of liquid feed twice daily for 98 days and their body weight, average daily gain, feed intake, feed efficiency, and health status were monitored. To promote rumen development, the animals received a measured amount of concentrate feed. In addition, all calves had ad libitum access to Digitaria hay and clean fresh drinking water. All data were analysed in SAS using the General Linear (PROC GLM) procedure with repeated measures that adjusted for fixed and random effects. The results showed that replacing whole milk with 25% DM soymilk improved the feed conversion ratio and calf performance compared to the control group. Calves that received 25 and 50% DM soymilk had significantly (P<0.05) higher total weight gain than the control group. This suggests that soymilk replacer had a positive effect on the growth of the calves up to a certain point. Calves fed 25% DM of soymilk were more efficient with lower total dry matter intake and feed conversion ratio and higher average daily gain compared to the control group. The reason for the peak at 25% DM of soymilk may be related to the optimal balance between the protein and energy content of the diet, as well as the digestibility and palatability of the feed. However, as the proportion of soymilk increased beyond 25% DM, the performance of the calves declined. The calves that received 75% DM of soymilk had the lowest final live weight, total weight gain and average daily gain. This indicates that excessive inclusion of soymilk may have negative effects on the health and nutrition of calves. Therefore, this study indicates that partial replacement of whole milk with up to 25% DM soymilk in calves' diets can improve feed efficiency and growth performance. The findings suggest that soymilk can partially replace whole milk in preweaning calf feeding programs without compromising performance.

Full text

Soymilk Replacer versus Whole Milk: Effects on Calf Performance
I.U. GadzamaAC, and S.M. YashimB
ACUniversity of Queensland, Gatton, QLD, 4343
BAhmadu Bello University, Zaria, Nigeria, 810105
CCorresponding author. Email: i.gadzama@uq.edu.au
Abstract
The demand for milk and its importance in human nutrition limits its availability for neonatal dairy calves,
especially in regions where the local breeds of dairy cows have low genetic potential for milk production.
Calves are prone to stress during the preweaning period (2-3 months) and therefore need adequate
nutritional management (Jenkins, 2021). The early life nutrition of calves has a lasting impact on their
productivity and fertility throughout their lifespan (Drackley, 1999; Roy et al., 2016). To enhance the
survival and health of young pre-ruminants, alternative sources of milk can be provided (Khan et al.,
2012; Dairy Australia, 2020). Soymilk is a plant-based alternative to cow's milk that is made from
soybeans (Gadzama et al., 2017). It contains protein, fat, carbohydrates, vitamins and minerals, but it
also has some anti-nutritional factors (ANFs) that can interfere with the digestion and absorption of
nutrients by calves. However, adequate processing can inactivate ANFs in soymilk making it a promising
alternative as a milk replacer (Gernah et al., 2013; Gadzama et al., 2017; Dairy Australia, 2020). This
study evaluated the effect of substituting a portion of whole milk with soymilk on the preweaning growth
performance of dairy calves. We hypothesized that soymilk could partially replace whole milk without
compromising the growth performance of preweaning calves. A total of 16 Holstein x Bunaji calves with
an average initial live weight of 34.8 ± 0.7 kg (mean ± standard deviation) were randomly assigned
to one of four dietary treatments: 1) control, without soymilk; 2) low, with 25% DM soymilk; 3) medium,
with 50% DM soymilk; 4) high, with 75% DM soymilk in a completely randomized design. Each calf
received 2 litres of liquid feed twice daily for 98 days and their body weight, average daily gain, feed
intake, feed efficiency, and health status were monitored. To promote rumen development, the animals
received a measured amount of concentrate feed. In addition, all calves had ad libitum access to Digitaria
hay and clean fresh drinking water. All data were analysed in SAS using the General Linear (PROC
GLM) procedure with repeated measures that adjusted for fixed and random effects. The results showed
that replacing whole milk with 25% DM soymilk improved the feed conversion ratio and calf performance
compared to the control group. Calves that received 25 and 50% DM soymilk had significantly (P<0.05)
higher total weight gain than the control group. This suggests that soymilk replacer had a positive effect
on the growth of the calves up to a certain point. Calves fed 25% DM of soymilk were more efficient
with lower total dry matter intake and feed conversion ratio and higher average daily gain compared
to the control group. The reason for the peak at 25% DM of soymilk may be related to the optimal
balance between the protein and energy content of the diet, as well as the digestibility and palatability
of the feed. However, as the proportion of soymilk increased beyond 25% DM, the performance of the
calves declined. The calves that received 75% DM of soymilk had the lowest final live weight, total
weight gain and average daily gain. This indicates that excessive inclusion of soymilk may have negative
effects on the health and nutrition of calves. Therefore, this study indicates that partial replacement of
whole milk with up to 25% DM soymilk in calves’ diets can improve feed efficiency and growth
performance. The findings suggest that soymilk can partially replace whole milk in preweaning calf
feeding programs without compromising performance.
Keywords: Milk-replacer, soymilk, preweaning, calf, performance
Table 1: Performance parameters of calves fed soymilk replacer
Parameter
Inclusion levels of soymilk
Control
(0%)
Low
(25%)
Medium
(50%)
High
(75%)
SEM
Initial live weight, kg
34.50
35.50
34.00
35.25
2.43
Final live weight, kg
100.50ab
109.75a
106.00a
93.50b
3.83
Total weight gain, kg
66.00b
74.25a
72.00a
58.25c
2.64
Average daily gain, kg
0.67b
0.76a
0.73ab
0.59c
0.03

Dry matter intake, kg/day
4.25a
4.18c
4.22b
4.22b
0.01
Feed conversion ratio kgDMI/kg gain
6.31b
5.52a
5.74ab
7.11c
0.29
a
-cMeans with different superscripts within the same row differed significantly (P <0.05).
References
Dairy Australia. (2020). Understanding calf milk replacers. https://cdn-prod.dairyaustralia.com.au/-/media/project/dairy-
australia-sites/national-home/resources/2020/07/09/understanding-calf-milk-replacers-factsheet/understanding-calf-milk-
replacers-factsheet.pdf?rev=50e229990c904b98953c73fafdf08ae1
Drackley, J.K. (1999). Critical Evaluation of Feeding Options for Replacement Calves. Advances in Dairy Technology, 11: 141 –
152.
Gadzama, I. U., Yashim, S. M., Abdu, S. B., Makun, H. J., Barje, P. P., & Achi, N. P. (2017). Feed intake, growth performance
and nutrient utilization in Friesian x Bunaji calves fed soymilk-based milk replacer. Journal of Animal Production Research, 29(2),
96-111.
https://www.researchgate.net/publication/322419499_feed_intake_growth_performance_and_nutrient_utilization_in_friesi
an_x_bunaji_calves_fed_soymilk_based_milk_replacer
Gernah, D.I., Ikya, J.K., Ojobo, H.E. and Oni, O.K. (2013). Effect of Cooking Temperature on Some Quality Characteristics of
Soy Milk. Advance Journal of Food Science and Technology, 5(5): 543 – 546.
Jenkins, K. H. (2021). Managing Early Weaned Calves. UNL BeefWatch. Retrieved from
https://beef.unl.edu/beefwatch/2021/managing-early-weaned-calves
Khan, M.A., Sajj, G., Bahkt, A., Khan, D., Iqbal, M.K., Pervez, F. & Pakistan, H. (2012). Effect of Milk Replacer on Performance
Parameters of Different Bovine Breeds. Journal of Nutrition, 11(12): 1190 – 1193.
Roy, B.K., Sarker, N.R. Alam, M.K. & Huque, K.S. (2016). Growth Performance of Calves Fed Shoti, Wheat and Soybean Based
Milk Replacers. Bangladesh Journal of Livestock Research, 19(1and2): 33 – 43.