Some thoughts on… Maternal Ability

By Joe C. Paschal · Livestock Specialist, Texas A&M AgriLife Extension.

What is maternal ability? Milk production or added weaning weight due to additional milk production (maternal weaning weight) comes to mind as does the dam’s ease of calving (maternal calving ease). Another measure of maternal ability is how the dam responds to or cares for her calf, especially when confronted by an intruder (docility). I include these in my definition of maternal ability plus other traits that reflect reproductive ability as well as fertility. In fact, there are 20 or more characters that likely impact maternal ability.

In addition to maternal calving ease and maternal weaning weight (or milk) and docility, earlier puberty should be considered a maternal trait although some will classify it as a reproductive or fertility trait. Milk is certainly a maternal trait but how much milk a cow needs to produce is an age-old question. I think enough to wean a decent calf while maintaining body condition and rebreeding early enough to calve within 365 days without additional supplement.

Along with milk production, attention to the three “S’s” of udders – size, shape and support and the spacing, length, and diameter of teats on them are very important. We have all heard the saying “as useless as teats on a boar hog”. Well, it turns out that the number of teats on a boar are good indicators of the number of functional teats on his daughters! I do not suggest counting teats on your bulls, but i do suggest you pay more attention to the udders and teats on your cows.

Mature size is a maternal character. Moderate sized cows and bulls reach puberty earlier and in a breed that exhibits later puberty as a breed characteristic, it would be useful to moderate size. Moderating size affects other characters besides puberty, it lowers nutrient demand and requirements and supplementation costs.

Moderating mature size (and weight) would also have an effect on structural soundness. How can a cow raise a calf without being structurally sound? Soundness begins with the feet and ends with the spine but there are many indicators in between of soundness. Hoof size and shape, pastern strength, correctness of legs, shape of pelvis all affect the ability of the cow to be maternal and long lived.

A great deal of research has been done on the production and economic effects of moderating cow size in many breeds, there is no reason to think that the results would be less desirable in Brahmans. Moderate size cows (and bulls) may be “easy keepers” meaning that their nutrient requirements are met more easily, they stay fleshier (in better body condition), and are likely more fertile and productive cows as a result. As to what is an optimal mature size, that will depend on your market. The USA cowherd, consisting of many different breeds probably is about a frame score 4 (48 – 50 inches at 2 – 4 years of age) while the frame score of most bulls might be a 6 or 7 (56 – 58 or 58 – 60 inches). How big are your cattle?

In addition to early puberty, desirable maternal ability includes fast return to estrus and rebreeding after calving. Part of this response is the cow’s ability to maintain herself during and after pregnancy nutritionally (moderate size and milk production) and to calve easily. Less stress and damage to the reproductive tract shortens the time to return to estrus and rebreeding.

First service conception rate is a maternal character. If the bull’s semen is fertile, why do some cows take more than one service to become pregnant while others require several services? Cows are responsible for ensuring implantation of the fertilized egg after breeding, often within a week or two after breeding. If implantation does not occur, the cow returns to estrus. Early pregnancy losses are real, some are due to disease, others are due to genetics. The same is true for maintenance of pregnancy, once a female is safe in calf, she should remain so barring disease or injury.

I haven’t left out those other traits that Brahman and Brahman influenced cattle are noted for and contribute to maternal ability. Heat and humidity tolerance is extremely important to the survival of the early embryo and fetus. Parasite and disease resistance are also high on the list. Having those attributes genetically as a breed does not exempt management to improve the ability of the animal’s resistance or tolerance, it only enhances them.

The last character of value, and of more value to the commercial cattle person than the purebred breeder, is longevity. Bos indicus cattle and their crosses are more maternal and longer lived than non-Bos indicus cattle if they are properly selected and managed. There are many factors that affect longevity, some of them affected maternal ability or fertility too. All of these characters can be selected for (and improved) in your herd, you have the desire to monitor them and record them and to select animals as parents to improve them, all you need is time.