The role vitamins play in colostrum quality

Neither vitamin A nor E cross the placenta in amounts high enough to meet requirements of newborn calves, which increases the importance of recognizing seasonal changes in forage vitamin concentration, the role vitamins play in colostrum quality and the importance of supplementation.

Adele Harty

High-quality green forages such as summer pasture and alfalfa are the best sources of vitamin A and E. The challenge in the northern Great Plains, however, is access to these forages year-round. Knowing the role vitamins play in the newborn calf and how to ensure proper nutrition through colostrum can improve health and performance.

Spring 2018 presented challenges for cattle producers across the northern Great Plains as a result of a drought in 2017 followed by a colder winter with limited feed resources. Additionally, prices increased dramatically for vitamins A and E due to manufacturing issues that created supply shortages. When calving started, there was a higher incidence of “weak calf syndrome” or “failure to thrive.” When all of the factors from the year combined, a common link seemed to be vitamin A and E deficiency in cows.

Vitamin A

Approximately 70 to 90 percent of the cow’s body reserves of vitamin A are in the liver. If dietary vitamin A levels are provided beyond requirements, liver reserves are developed. Research indicates liver stores may be available for approximately four months in mature cows. However, the amount of storage is difficult to predict, and relying on liver stores to provide adequate levels of vitamin A is not recommended.

This becomes particularly important during winter when utilizing low-quality or stored feeds for longer time periods. Because liver storage is variable, it may not be adequate to provide sufficient vitamin A in colostrum. Providing supplemental vitamin A may be necessary to achieve expected calf performance. Pregnant heifers and cows require 1,273 international units (IU) per pound of feed, while lactating cows require 1,773 IU per pound of feed.

Research has shown vitamin A-rich colostrum can have positive effects on metabolism, health and growth of young ruminants. Calves are born with very low liver reserves; therefore, they have to ingest high amounts of vitamin A through colostrum immediately after birth.

If vitamin A deficiency exists in cows, symptoms affecting newborn calves may include weakness, blindness, incoordination or stillbirths. If the calf is born alive and blind, it will have trouble gaining balance and lack the instinct to nurse.

Oftentimes, vitamin A-deficient newborn calves experience a very severe, often fatal, diarrhea. Calves born with low vitamin A liver stores should receive a minimum of 7,500 IU per 100 pounds of bodyweight, with three to five times this amount recommended to build up liver stores in the first few months of life. Vitamin A level in 8 pounds of colostrum from cows with adequate vitamin A is over 26,000 IU, which should meet newborn calf requirements.

Vitamin E

In contrast to vitamin A, there is very little vitamin E storage in the body. In addition, forages can lose up to 80 percent of vitamin E as it matures or is put up for hay in longer-term storage. The amount of vitamin E loss in forages can vary greatly depending on stage of maturity at harvest and drying time. Once hay is placed in storage, 50 percent of the remaining vitamin E can be lost within a month. Longer storage results in lower vitamin E concentrations. These factors increase the importance of a supplementation program that overcomes deficiencies.

Vitamin E requirements are unknown for most classes of cattle; however, research has shown increased colostrum vitamin E levels decreased incidence of scours and increased average daily gains as a result of feeding supplemental vitamin E during the last trimester of gestation. These studies confirm winter- and spring-calving beef cows and their calves benefit from 1,000 IU per day of supplemental vitamin E during the last 60 to 90 days of gestation.

White muscle disease is a characteristic of vitamin E deficiency, with symptoms including leg weakness, stiffness of gait and muscle degeneration. Additionally, calves have difficulty standing, exhibit crossover walking and have an impaired suckling reflex. In milder cases, clinical signs can include stiffness and difficulty standing, but rapid recovery can be achieved with a vitamin E-selenium injection followed by dietary supplementation.

Supplementation

Most commercial mineral supplements include a vitamin package with vitamin A and E. Levels vary depending on the product and recommended intake. Reading the feed tag becomes extremely important in determining how a product meets the cow’s requirements to provide the greatest opportunity to produce high-quality colostrum for the calf. If the supplement has 300,000 IU per pound vitamin A, and the recommended intake is 2 ounces per day, cows would receive 37,500 IU of vitamin A from the supplement.

A 1,400-pound cow during gestation requires 40,736 IU vitamin A per day, while its requirement increases to 56,736 IU per day after calving based on intake of 2.2 percent bodyweight dry matter (DM) basis. If that same supplement has 300 IU per pound vitamin E, cows would receive 37.5 IU per day from the supplement. The research discussed previously showed the benefit of 1,000 IU per day supplemental vitamin E; therefore, it may be advantageous to provide additional vitamin E.

When purchasing mineral supplements, keep in mind: Vitamin A is rapidly destroyed by oxygen, heat, light and acids. Additionally, moisture and trace minerals reduce vitamin A activity in feeds. Several factors affect the stability of vitamin A in processed feeds, but keep in mind: The longer a product is stored, the more vitamin A will continue to be lost.

Providing a balanced vitamin and mineral supplement is important for many aspects of cattle health and performance. Take time to evaluate supplements to ensure they will provide adequate levels of vitamin A and E to increase colostrum quality and give calves the best possible start.

PHOTO: High-quality green forages are the best source of vitamin A and E, so when cows don’t have access to these forages year-round, supplementation is needed to meet the requirements of newborn calves. Getty Images.