Negative Effects of a High Level of Nutrient Intake on Mammary Gland Development of Prepubertal Goats

¹ Department of Animal and Food Sciences, University of Vermont, Burlington 05405
² William H. Miner, Agricultural Research Institute, Chazy, NY 12921

Ten French Alpine kids were used to determine whether mammary development was altered by level of nutrient intake during the prepubertal period. At 6 wk of age, kids were paired on the basis of BW and assigned to an ad libitum or restricted diet of milk from Jersey cows. Kids on the restricted diet were fed 70% of their pair mate's milk intake for 4 wk and then 50% for 9 wk. Low quality grass hay was available for all kids. The ADG was greater for kids fed for ad libitum intake. Kids fed for ad libitum intake had larger mammary glands and increased adipose deposition. Measurement of hydroxyproline indicated that connective tissue increased with gland size. Kids on the restricted diet had more DNA and protein per gram of mammary gland, indicating greater secretory development. Goats can be used as a model to study the effect of level of nutrient intake on hormones and growth factors that regulate mammary gland development.

Key Words: mammary development • nutrition • kids • goats

Submitted on September 26, 1994
Accepted on April 4, 1995