Calf-feeding experiments in the nutrition herd at Beltsville were being continually disrupted by deaths from scours, pneumonia, and other ailments, when the hopeful reports on the control of calf scours were being made by the Wisconsin station. No division of animals into experimental and control groups was made, but nearly all the calves on feeding experiments from December 1943, to March 1945, received the supplements recommended to control "nutritional scours." During this period of about 15 months, 64 calves received capsules containing ascorbic acid (500 milligrams) , and niacin (100 milligrams). Each day the calves also received 20,000 to 40,000 International units of vitamin A from cod-liver oil. Eighteen of these calves, or 28 percent, died before 65 days of age. Eleven of the 18 died before 30 days of age. We did not keep a careful record of the condition of the feces during the first part of the period but of the 18 that died, autopsy reports of the station veterinarian showed scours as the cause of death in 13 cases, scours and pneumonia in 2 cases, and pneumonia in 3. Thirteen of the calves that died had received two capsules daily for the first 5 days and one capsule daily for the next 10 days if they lived that long. Thus, the calves that died had more than twice the amount of each of the supplements included in the capsules reported by the Wisconsin station as capable of controlling 90 percent of "nutritional scours" in calves.

Very few of the calves fed "scour-prevention capsules" at Beltsville were treated with sulfa drugs or any other therapeutic agents; however, one such calf might be cited as a specific case. A Jersey steer received colostrum for 3 days and then skim milk. Starting the day after birth 20 cubic centimeters of cod-liver oil or about 36,000 International units of vitamin A were fed daily. For 4 days starting the day after birth, the calf received two of the capsules daily or a daily dose of 1 gram of ascorbic acid and 200 milligrams of niacin. For the next 11 days the calf was fed one capsule. Although this dosage was much more generous than the Wisconsin recommendations, the calf started scouring on the fifth day after birth. The calf scoured from the fifth to the thirty-fourth day except for the eleventh, twelfth, and thirteen days, when the feces were soft. From the thirty-first day combined sulfaguanidine and sulfathiazole treatment was administered for 8 days. Scours were not observed after the fourth day of this treatment.

Sulfa Drugs for Calf Scours

The use of sulfa drugs began in March 1945, when we realized that the "scour prevention capsules" were not preventing deaths from scours of dairy calves. While there was some variation in dosages, all calves received at least 2 grams daily of either sulfaguanidine or sulfathiazole. These protective doses of sulfa drugs were usually started within 2 or 3 days after birth (sometimes on the day of birth) and were continued for 30 days or longer. If scours developed the dosage was increased for a few days until the scours subsided or the calf died. The severity of scours and the number of deaths was much less during the sulfa drug period than when "scour-prevention capsules" were fed.

From March 23, 1945, to January 19, 1946, 46 calves were placed on feeding experiments. Nearly all were taken from the maternity barn before 3 days of age. Of the 46 calves, 5 died. This gives a mortality rate of 10.6 percent, as compared with the loss of 28 percent among 64 calves fed "scour capsules." Of the 5 calves that received sulfa drugs that died, 1 seemed unable to swallow and consumed less than 1 pound of milk daily for the 6 days that it survived; 1 died at 1 month of age while running to the scales to be weighed, apparently in perfect health. Of the 5 calves that died only 3 had any history of scours.

Those responsible for the feeding of calves should be cautioned not to rely on the use either of sulfa drugs or large doses of vitamin A to prevent scours, pneumonia, or other infections among calves kept in unsanitary quarters. Calf pens should be kept clean and dry and they should be thoroughly disinfected frequently. The intensity of infections among calves is apt to be greater where large numbers of calves are continuously housed together than when only a few calves are kept.

THE AUTHOR

Henry T. Converse is a dairy husbandman in the Division of Nutrition and Physiology, Bureau of Dairy Industry. For 20 years Mr. Converse has conducted research in nutrition of dairy cows and calves, including energy requirements for growth and milk production and the calcium and vitamin A requirements of calves.