Maximizing Reproductive Performance in Beef Cows Keith VanderVelde Livestock Agent Marquette Co. UWEX Spring 2004 Cow Calf Programs Mauston-March 6 Plover-March 13 Montello-March 20

Reproductive Performance Cows Job Description is ??

Reproductive Performance Cows Job Description 1.Produce & Wean Live calf each 365 Year Requires regular breeding 2.Make a positive return to labor & management Dependent on Feed Cost Calf Prices

Reproductive Performance It all starts with the heifers 1.Reach Puberty at 10 months of age 1.Varies by breed-Jersey to Brahman 2.Use 65% of mature weight as guide when to breed 3.Breed heifer to calve 30 days in advance of cows 1.Allows heifers more time post partum 2.Requires additional feed and labor

Reproductive Performance It all starts with the heifers 1.At calving 1.Assist after 30 minutes of hard labor 2.Feed heifers to weigh 85% of mature size 3.Have heifers on gaining weight 30 prior to calving thru rebreeding 4.Body condition scores should be 5 or 6

Reproductive Performance Cows need regular reproduction 1. Cows must rebreed 85 days after calving to stay on 365 day calving interval 2.Cows need to be gaining weight from calving to rebreeding 1.Calves will compete for energy 2.Energy and protein needs increase by 50% after calving

Reproductive Performance How to manage cows to insure regular reproduction 1.Feed cows to gain from mid-gestation to 90 days after calving 2.Body Condition Cows in the fall and spring 3.Consider calf removal as a management tool 4.Provide adequate high protein, high energy feed for period from calving to rebreeding 1.Consider hold back the best feed for this period 2.Supplement with grain and Soybean Meal

Maximizing Reproductive Performance Vaccination Programs –BVD and IBR –Leptospirosis –Campylobacteriosis(Vibro) –Trichomoniasis(Trich)

Maximizing Reproductive Performance Vaccination Programs –Yearly vaccinations recommended for open herd with animals coming into herd –Or Vaccinate in response to disease outbreak is best suited to closed herds

Maximizing Reproductive Performance Vaccination Programs –Recommended BVD IBR PI3 Bovine Respiratory Syncitial Virus(BRSV) Clostridial strains Haemophilus somnus Pasteurella haemolytica Lepto

Maximizing Reproductive Performance Conduct annual Pregnancy Checks –Can be done 45 days after bulls are removed –Or should be done 4 months after bulls are introduced to cows for rebreeding –Open cows should be culled or moved to a alternate calving program—Fall Calving –BULL Management Fertility Check bulls 60 days before breeding season

Maximizing Reproductive Performance Leaving the Bull Out Too Long –Length of Breeding Season Matters –Oklahoma, Texas, New Mexico Study, Glenn Selk, OSU Extension Animal Reproduction Specialist –394 Ranch Records –Positive Relationship between number of days of breeding season on cost per hundred weight of calf weaned –For each additional day of breeding season the cost per cwt increased by 4.7 cents and pounds of calf weaned per cow decreased by pound

Maximizing Reproductive Performance Leaving the Bull Out Too Long Conclusions: –365 day breeding season results in additional cost of $13.63 per hundred weight of weaned calf as opposed to the 75 day breeding season. –365 day breeding season results in 46 fewer pounds sold per cow per year when compared to 75 day breeding season –On a 50 cow operation the impact is: Two thousand ninety one (2291) less lbs sold An increased cost of $68.15 per head for 500 lb calf $3408 increased cost assuming 100% conception rate

Body Condition Scoring The main factors determining the pounds-of-calf- weaned in a beef herd are growth rate of the calf, the proportion of cows pregnant and the calving patterns of the cow herd. Producers working with beef cows should: 1) Know how to estimate body condition 2) Understand the influence body condition has on production. 3) Know how and when to change body condition. 4) Be able to calculate the costs and returns for changing body condition.

Practical Importance of Body Conditioning Scoring Body condition scoring is a subjective measure of the amount of fat in an animal’s body. Body condition influences production in a beef cow herd in three ways: 1) Growth rate of a calf suckling a thin cow is decreased. 2) Pregnancy rate in thin cows is lowered. 3) Thin cows become pregnant later in the breeding season and thus calve later in the following year.

Determination of Body Condition Two methods currently used to determine body condition are: 1)Measurement of covering over the ribs, shoulder and back. 2) Measurement of covering over the short rib and tailhead. Both methods appear to be accurate, and the system used is largely a matter of preference. The Nebraska System scores cows from 1 (thin) through 9 (fat) and the Scottish System from 1 (thin)to 5 (fat).

1……………………………emaciated 2……………………………very thin 3……………………………thin 4……………………………borderline 5……………………………moderate 6……………………………good 7……………………………fleshy 8……………………………fat 9……………………………extremely fat

Pregnancy Rate and Post-Partum Estrus Studies have shown a decrease in pregnancy rates in thin cows Cows that were grazed on similar pastures during a 120-day breeding season varied in pregnancy rate from 23% for body condition score ‘2’ to a 95% pregnancy rate for body condition score ‘7’ Other studies have shown similar results with the difference ranging from 10% to 20% less in pregnancy rates for cows with body condition score of ‘4’ or less. The reason the pregnancy rate is lowered is cows that are in thin condition have a delay in the onset of estrus.

Body condition and pregnancy rate in a group of cows in Florida BODY CONDITION NEAR CALVING 2345&67 very thinthinborderlinemoderategood No. Of Cows Pregnant After Breeding 60 days (%) days (%)

Missouri Trial Young Beef Cows Condition score at calving Condition score change after calving to day

Proportion of cows showing estrus at different times after calving Body Condition ThinModerateGood No. of Cows Days post-calving 303 a a % of cows showing estrus by this time.

Condition at calving determines rebreeding rate

Post-Calving Nutrition It is desirable to maintain cows at a BCS of 5 or more through breeding. Cows less than 5 need to be fed to improve their condition, which is expensive to accomplish while nursing a calf. Research shows that moderate condition cows losing weight after calving tended to show estrus sooner after calving than cows gaining weight.

Post-Calving Nutrition These differences continued until 80 post- calving. This information indicated that body condition at calving has more influence on the onset of estrus than feed level post- calving.

Growth Rate of the Suckling Calf and Milk Production of the Cow Milk consumption and calf growth rates were lower in thin conditioned heifers than those that were in moderate condition. The energy level received post-calving had little influence on milk production or calf growth in heifers.

Growth Rate for the Suckling Calf and Milk Production of the Cow This data indicates that cows that calve thin will have lower milk production and, consequently, slower calf growth than those calving in moderate or good condition.

Improving Production by Changing Body Condition Improvement in body condition will improve the pounds-of-calf-weaned in three ways: 1) Calves suckling a cow in moderate or good condition grow faster than calves suckling a thin cow. 2) More cows in moderate or good body condition will be pregnant at the end of the breeding season. 3) More cows in moderate or good body condition will calve early next year.

Weight Changes Needed to Change BCS a Last 100 days of pregnancy.

What is “GOOD” Body Condition?

Body Condition 3

Body Condition 6

Body Condition Scoring Tips Have a neighbor score your cows Accept his scores We often see our own cows too often If in doubt about condition put in chute and feel animal over the ribs. Feed to improve to desired condition If cows are too fat 7+ do not put on diet until rebreeding has occurred