Group Housing Systems for Calves

Group Housing Systems for Calves
6/15/2017

Group housing systems are commonly associated with use of computerized automatic calf feeders, though autofeeders are not required for housing calves in groups. Some group-housed calves may be fed by simple “mob” feeding systems or ad libitum through a simple nipple connected to a large milk tank. The presentation by Dr. James made several recommendations for managing calves in a group-housed system:

1. House calves individually for the first 3-7 days.

2. Calves in a group system must receive enough colostrum in the first 24 hours to achieve a minimum of 5.2 grams of total protein/100 milliliters of serum when blood is sampled at 24-72 hours after birth.

3. Facilities must be well ventilated and drained. The Dairyland Initiative website (https://thedairylandinitiative.vetmed.wisc.edu/) is an excellent resource for planning calf facilities. Limit group size to 15 calves and allow at least 35 square feet per calf. Calves with 45-50 square feet per calf have better health scores. Herds without positive pressure ventilation have been shown to have greater morbidity and mortality.

4. Sanitation of equipment is critical to the success of the program. Internal surfaces of autofeeders should be washed 4 times per day and all outside surfaces (including the nipple) once daily.

5. Milk replacers used should mix at lower temperatures than conventional milk replacers. Many autofeeders use water only at about 105°F.

6. Feeding plans should allow calves to double birth body weight by 56 days of age. Feeding plans generally utilize greater amounts of milk (8 liters/or 2 gallons) or more per day. Some group housing systems allow calves access to acidified whole milk ad libitum. Computerized feeding systems allow the user to program changes in amount of solids and water used to mix milk replacer. However, technical support and the dealer’s ability to program the autofeeders is quite limited and a problem on many farms. It is best to reach peak milk allowance by 14 days of age.

7. Personnel management and training is essential. New methods of training employees to properly utilize group housing and sophisticated feeding equipment are necessary.
Behavior of group housed calves will be quite different from calves housed individually. Some data suggest that early grouping of calves may improve post-weaning growth whereas calves housed individually may experience reduced post-weaning growth. Cross-sucking is a significant problem with group housed calves – feeding more milk or making nipples available may reduce this behavior.

Modeling Effects of Liquid Intake on Digestion in Calves

Modeling Effects of Liquid Intake on Digestion in Calves by Dr. Jim Quigley from Provimi North America reviewed recent research conducted at the Nurture Research Center in calves fed varying amounts of milk replacer. Several studies wherein calves were fed amounts of milk replacer ranging from about 1 lb. per day to >2 lbs. per day. Total tract digestion of nutrients was measured at various time points during each 16-week study.
Digestion of starch and neutral detergent fiber (NDF) in calf starter was generally low when calves were fed high amounts of milk replacer. This is very likely due to the limited starter intake and lack of rumen development in these calves. On the other hand, digestion of crude protein and fat were well developed, probably because calves have well developed ability to digest fat and protein from either milk or starter feed.
Total tract digestion of starch reaches nearly 100% within a few weeks of life and is likely driven by development of starch-digesting enzymes by the calf. Total disappearance of starch is >95% by 8 weeks of age, regardless of the amount of milk replacer consumed by the calf. An important question still unresolved is the site of disappearance – rumen, small intestine, or large intestine.

After weaning (usually at 42 or 49 days), the digestion of NDF appears to depend on the type of starter fed. Calves fed high NDF pelleted starters have higher NDF digestion whereas calves fed high starch texturized starters have consistently lower NDF digestion. It is not clear whether the lower NDF digestion is due to the form of the starter (pelleted or textured), amount of NDF or starch, or some combination of both factors. However, all studies consistently show that amount of starch in starters is positively correlated with greater growth.

Using the 2001 Dairy NRC as a guide, the authors estimated the total digestable nutrient (TDN) concentration of the starter feed at various ages. The sum of digestible non-fiber carbohydrate (NFC), NDF, protein and fat were used to estimate TDN; the TDN value was then used to estimate amount of starter metabolizable energy. This calculated ME value was then compared to the values calculated by the current 2001 Dairy NRC using standard values. The authors found discrepancies between the 2001 Dairy NRC values compared to the values estimated using the experimental data. When calves were fed large amounts of milk, the estimated ME available in calf starter was markedly lower than the ME calculated by the NRC. This was mainly due to lower digestion of NDF. Thus, calves fed higher milk and higher NDF starters would likely be least able to extract nutrients from the starter. As a result, growth would be impaired.

This approach of monitoring development of digestion and calculating amount of nutrients available for growth will give the Provimi researchers an ability to more accurately predict nutrient availability in calf starters and will improve our ability to formulate calf starters depending on the milk feeding program.

Quigley’s Quick Review:
Tri-State Nutrition Conference Calf Papers
Dairy Nutrition Newsletter
June 2017
©2017 Provimi North America, Inc.

Tags: Calves