Nutrition – Management of Dairy Sheep – Goats on Pasture

1998 Annual Report for LNE98-108

Project Type: Research and Education
Funds awarded in 1998: $151,190.00
Projected End Date: 12/31/2002
Matching Federal Funds: $6,252.00
Matching Non-Federal Funds: $71,616.00
Region: Northeast
State: New Hampshire
Project Leader:

Nutrition – Management of Dairy Sheep – Goats on Pasture

Summary

Summary
We have completed two years of a three-year project to determine the optimum level of concentrate supplementation for lactating dairy sheep and goats grazing intensively managed, high quality pastures. Our work is showing that dairy sheep grazing high quality pasture need very little concentrate supplementation. For a 100-ewe flock, this could mean an annual savings of over $2,000 for purchased feed. For the dairy goats, our work is showing that even while grazing high quality pasture, high yielding dairy goats require significant levels of concentrate supplementation to reach their milk production potential.

Objective
To determine the optimum level of concentrate supplement to feed high yielding dairy sheep and goats grazing intensively managed pastures.

Approach
This project will use a team approach involving farmers, researchers, UVM and UNH Cooperative Extension, and NRCS personnel. The project will be conducted on two farms, the Major Farm in Westminster, Vermont, which has dairy sheep, and the Quarrier Farm in Acworth, New Hampshire, which has dairy goats.

The experimental design was developed by Dr. James Welch at the University of Vermont. In year one, we will conduct two experiments using a Randomized Complete Block Design. All available animals will be identified according to previous milk production, genetic potential for milk production, number of offspring nursed, weight, and age. Animals that are similar will be assigned to blocks of three according to the above criteria. Animals within blocks will be randomly assigned to one of the three treatments laid out below.

In the first experiment, we will look at the effect of different levels of supplements on early lactation. The animals on each farm—150 ewes and 60 does, respectively—will be divided at weaning into three treatment groups. Each animal will be identified by an ear tag or tattoo and by a colored leg band for quick identification at milking.

The three groups will receive different levels of a nutritionally complete supplement designed by Dr. Hogue at Cornell University. This supplement will be designed using the current information available on feeding high-milk-producing sheep and goats, and will use readily available feedstuffs. The National Research Council’s (NRC) “Nutrient Requirements of Sheep,” sixth edition, 1985, and “Nutrient Requirements of Goats,” 1981, will be used to determine the nutrient requirement baseline on which the level of supplementation will be determined.

Group 1 will be the control group. All animals this group will receive pasture plus a minimal level of supplement—ten to fifteen percent of the NRC requirement.

Group 2 will receive pasture plus a medium level of supplement—30 to 35 percent of the NRC requirement.

Group 3 will receive pasture plus a high level of supplement—50 to 60 percent of the NRC requirement.

All three groups will be grazed together. They will be allowed unlimited consumption of the same high quality pasture. At milking, each animal will receive the supplement according to which of the three groups it has been assigned. After milking, the animals return to a single group. Animals will receive new pasture after every milking.

All animals will receive care at the best management level from the last trimester of pregnancy through to weaning. Animal care will be monitored weekly by extension specialists or a licensed veterinarian. Weaning will occur at day one or two postpartum for does, and day 25 to 30 postpartum for ewes. As animals are weaned, the first experiment will begin and will continue until all animals have been on the experiment for a four-week period.

At the completion of the first experiment, the data will be immediately analyzed. The second four-week experiment will be conducted as soon as the data from the first experiment has been analyzed. The purpose of the second experiment is to look at the effect of different levels of supplementation on mid-to-late lactation. The same animals and the same experimental design will be used in the second experiment as was used in the first experiment.

The following measurements will be taken:
Weight. All animals will be weighed at the beginning of the last trimester of pregnancy, within one to two days postpartum, and at the beginning and end of each experiment period.

Milk. Milk will be weighed and analyzed weekly during each experiment for fat, protein, and somatic cell count. The milk will also be taste tested by an experienced milk grader. The milk will be analyzed at the New York DHIA lab.

Pasture. During each experiment, pasture dry matter yield will be measured and recorded at each change of pasture, or about every twelve hours. A rising plate pasture meter designed and made in New Zealand will be used for this measurement.

Soil. Soil tests will be taken at the beginning and end of each experiment. Soil tests will be done at the University of New Hampshire Analytical Lab and will measure pH, P2O5, K20, Ca and Mg.

Health. Animal health and overall condition will be assessed by a licensed veterinarian at the beginning of the last trimester and at the beginning and end of each experiment. Health treatments will be administered under the direction of the veterinarian.

An intern on each farm will assist in capturing and compiling data. All data compiled will be statistically analyzed. In years two and three, we will refine the feeding levels used in year one using a regression analysis design with several feeding levels. This will allow us to identify optimum feeding levels on which to base management decisions.

Results
After two years, the data from our work with the dairy sheep is showing no significant differences in milk yield or composition between low, medium, and high levels of concentrate feeding. In year three we will adjust our procedure so we can more easily compare the differences between individual sheep as well as differences in group averages.

The data from our work with the dairy goats tend to show the more typical lineal effect where the milk yield increases as concentrate level increase. We need to spend some more time analyzing the data before we make adjustments for the year-three trial with the dairy goats.

Impacts
If the results of the first two years are confirmed in year three, the most significant impact will be the recommendation to limit concentrate feeding of dairy sheep grazing high quality pasture to a half a pound a day rather than the more typical two pounds per day. For a 100-ewe flock, this could mean an annual savings of over $2,000 in feed costs. In addition, it would make it easier for a flock to become organically certified.

Reported December 2000

Collaborators:

David Major

Major Sheep Dairy
875 Patch Road
Putney, VT 05346
Heidi Smith

NRCS
Rt 12 Box 315
Walpole , NH 03608
Dr. Peter Erickson

Dairy Specialist
University of New Hampshire
129 Main Street
Kendall Hall
Durham, NH 03824
John Porter

UNH Dairy Specialist
University of New Hampshire
315 D.W. Highway
Boscawen, NH 03303
Dr. Stephen Major

DVM
Green Mt. Bovine Clinic
27 Bovine Ave
West Chesterfield, NH 03466
Dr. Stephen Judd

UNH Information Technology Specialist
University of New Hampshire
59 College Road
Durham, NH 03824
Mike Sciabarrasi

UNH Ag Business Management Specialist
University of New Hampshire
56 College Road
Durham, NH 03824
Carol Delaney

Small Ruminant Dairy Specialist
University of Vermont
212 Terril Hall
UVM
Burlington, VT 05405
Chester Parsons

UVM Sustainable Ag. Specialist
University of Vermont
278 S. Main Street
St. Albans, VT 05478
Dr James Welch

Professor Emeritus
University of Vermont
16 Raymond Road
Colchester, VT 05446
Dr. Douglas Hogue

Professor Emeritus
Cornell University
255 Morrison Hall
Ithaca, NY 14853
Keith & Leslie Quarrier

Quarrier Goat Dairy
PO Box 125
Alstead, NH 03602