Around 40% of the dairy operations in the US raised off-site their heifer replacements pre-weaning in large calf-raising facilities. Balancing calf-feeding strategies in large dairy operations is complex, as many calves must be provided with adequate calories and protein to support optimal growth several times a day. Moreover, diarrhea and pneumonia morbidity and mortality can peak during the pre-weaning period, leading some dairy operations to rely on antibiotics to maintain calf health. Nutrition plays a key role in the health and growth of dairy calves. However, raising heifer replacements is the second greatest production cost for dairy operations, and feeding during the pre-weaning period is the most expensive part of growing heifer replacements. 

We hypothesize that calves fed a higher-energy and protein-liquid diet during the pre-weaning period will improve production and reduce methane intensity compared to calves fed a low-nutritional diet. The goal is to test the effects of improved feeding plans for dairy calves and measure their methane intensity at different time points post-weaning with a previously validated GHG sensor. Then, we will model their emissions, predict them during the first lactation, and compare them with those of calves fed the conventional low-feeding profile pre-weaning.