More good bulls are wrecked between 8 and 15 months of age than any other point in their relatively short lives, says Dan Larson, PhD, Great Plains Livestock Consulting, Inc., Eagle, Neb. While underfeeding can be an issue, over-fat bulls are far more prevalent, Larson says.

Larson offers the following table of basic bull requirements which details requirements for various stages of growth:

Age, Months

NEg Mcal/lb

Crude Protein, %

Calcium %

Phosphorous %

Zinc ppm

Copper ppm

8-12

0.58

14.0

0.60

0.35

60

15

12-15

0.56

13.0

0.60

0.35

60

15

Larson says these are general recommendations and producers/veterinarians should check with their nutritionist to design rations for their specific situation.

Zinc, copper and manganese are extremely important to scrotal development and sperm production, Larson adds. The test have a high concentration of both zinc and manganese, and depletion of these trace minerals can result in small scrotal circumference and poor sperm quality.

Read more about bull management by clicking here and clicking on the September/October issue.