Nutrition Update
Volume 13 No.3, February 2003

One of the biggest factors affecting farm/ranch profitability is the herd's reproductive rate. Producers need female animals to produce one healthy calf each year, and improper nutrition, particularly in young females, can have a dramatic effect on reproductive performance. Special attention must be paid to developing and first/second calf heifers.

The nutritional status of replacement heifers will impact the onset of puberty and subsequent pregnancy rates. The herd's young, growing heifers require higher quality feeds since they can not eat as much dry matter as mature cows and their over all nutritional requirements are higher since they themselves are still growing.

Developing heifers' reproductive performance is linked to age, weight and breed. One of the biggest reasons for reproductive failure is due to inadequate weight at puberty and weight is the factor most easily controlled by the producer. Ideally, developing heifers should achieve 65-70% of their adult weight at breeding, approximately at 14-15 months of age. If the heifer does not achieve adequate weight levels, due to insufficient dietary energy levels, puberty can be delayed. Delayed puberty can delay breeding; therefore, the first calf heifers will calf later in the season and wean lighter calves. Too much weight gain can be just as detrimental to the heifers overall fertility. Excess fat, due to high energy levels in the diet, can be deposited in the mammary gland and thus inhibiting mammary development having a negative impact on future milk production.

In order for heifers to achieve desired weight gains and production levels it is critical that balanced rations be provided. Therefore, take advantage of services available from government agriculture offices or feed companies and have rations formulated. Feed developing and first calf heifers your higher quality feedstuffs and separate them from the rest of your herd. This allows them to compete at the feed bunk and maximize their genetic potential for growth and production.