By RAINEY ROSEMOND
It is widely assumed that calves receive all required nutrients from liquid feeds – milk or milk replacer – until weaning. However, it has been shown that offering grain at 3 days of age drastically improves rumen development by weaning. Additionally, the amount of grain and number of days grain is consumed prior to weaning is commonly used as a metric for ensuring a smooth transition. A commonly forgotten nutrient for rumen development is access to drinking water outside of the milk provided.
In general, whether group housed or individually housed, clean water should be provided to newborn calves starting from birth. Water provided to newborn calves should be clean and residue free to encourage intake. Water with residue, mold, or that is generally unclean could discourage newborn calves from drinking – negating any potential benefits of providing water. Like all equipment utilized by newborn calves, water buckets should be thoroughly cleaned and disinfected between each calf and group. Intake of contaminated water sources could contribute to disease spread or further health complications.
Pennsylvania dairy farms vary in their calf water availability with some farms providing water shortly after birth and others waiting until calves are moved into group housing. Water provided to calves varies in quality and cleanliness. If water quality is suspected of impacting calf health, a sample can be collected and tested by a laboratory. While not much research has been conducted about the added benefits of providing drinking water to calves from birth throughout the liquid feeding period, a recent study by Wickramasinghe et. al. (2019) provides clarity on this topic.
The researchers conducted a study comparing calves offered water at birth or 17 days later. Comparisons across both study groups included milk and starter intake, performance, health status, and nutrient digestibility.
Calves were offered free choice drinking water access and bottle fed 6 kilograms (kg) per day (2 kg at 3 feeding times) until 14 days of age and then milk increased to 9.6 kg per day. Results from the first 16 days of this study showed that drinking water intake alone was 0.75 ± 0.05 kg per day. The researchers concluded that the water requirements of calves are typically not met in a production setting as a large portion of dairy calves are fed less than 5.0 kg per day of milk replacer and not offered free choice water until 17 days of age.
Milk intake of calves offered supplemental water starting at birth increased through the preweaning process. Contrary to milk intake, starter intake remained unchanged between calves offered water starting at birth versus those offered water starting at day 17. As expected, water and starter intake both increased drastically when calves were partially weaned.
Although there was no difference in average dairy gain preweaning, calves offered water from birth tended to have increased body weight and heart girth compared to calves offered water at day 17. Post-weaned calves offered water starting at birth were taller, indicated by increased hip height, and had longer bodies than calves offered supplemental water starting at day 17. Average daily gain did not differ between the two groups, either preweaning or post weaning.
Offering supplemental water starting from birth had no impact on protein or starch digestibility and reduced apparent total tract digestibility of ether extract (fat). However, apparent total tract digestibility of both neutral detergent fiber and acid detergent fiber improved in calves offered water starting at birth. Improved fiber digestibility was related to a trend in improved feed efficiency (defined as average daily gain) post weaning. Water consumed free choice, without suckling stimulation, travels directly into the rumen rather than being diverted past the rumen into the abomasum. It has been established that water entering the rumen can affect rumen development, pH, feed mixing and passage, as well as volatile fatty acid composition. Unlike other nutrients, fiber digestion occurs mostly in the rumen and because of this improved fiber digestion typically suggests improved rumen function.
Scours in calves can be a common occurrence on some farms. It is assumed that supplemental water during the early days of a calf’s life will lead to increased scour events. However, offering calves water starting at birth had no impact on the number of scours or the number of days they lasted in the above research.
The researchers concluded that offering calves supplemental drinking water starting at birth resulted in better growth performance and apparent total tract digestibility of nutrients. Calves receiving supplemental water at birth had improved rumen function – leading to improved growth and feed efficiency; however, this was not directly measured. With expected increases in feed expenses continuing into next year, improving feed efficiency by offering drinking water at birth could be a focus for producers in their heifer raising programs.
Source : psu.edu