Dairy sheep production research at the University of Wisconsin-Madison, USA – a review

Abstract

Commercial milking of sheep is a new agricultural industry in the United States starting approximately 30 yr ago. The industry is still small, but it is growing. The majority of the sheep milk is used in the production of specialty cheeses. The United States is the major importer of sheep milk cheeses with 50 to 60% of annual world exports coming to the United States during the past 20 yr. Therefore, there is considerable growth potential for the industry in the United States. The only dairy sheep research flock in North America is located at the Spooner Agricultural Research Station of the University of Wisconsin-Madison. The research program started in 1993 and has been multifaceted; dealing with several areas important to commercial dairy sheep farmers. The East Friesian and Lacaune dairy breeds were compared and introduced to the industry through the research program. Both dairy breeds produced significantly more milk than traditional meat-wool breeds found in the U.S., but the two breeds differed in their production traits. East Friesian-cross ewes produced more lambs and slightly more milk than Lacaune-cross ewes whereas Lacaune-cross ewes produced milk with a higher percentage of fat and protein than East Friesian-cross ewes. Lactation physiology studies have shown that ewes with active corpora lutea have increased milk yields, oxytocin release during milking is required to obtain normal fat percentages in the milk, large udder cisterns of dairy ewes can allow for increased milking intervals, and short daylengths during late pregnancy results in increased milk yield. In the nutrition area, legume-grass pastures and forages with a higher percentage of legume will result in increased milk production. Grazing ewes respond to additional supplementation with increased milk yield, but it is important to match the supplement to the quality of the grazing. Ewes on high quality legume-grass pastures that are high in rumen degradable protein respond with increased milk production to supplements high in energy and/or high in rumen undegraded protein.

Influence of Maternal Factors (Weight, Body Condition, Parity, and Pregnancy Rank) on Plasma Metabolites of Dairy Ewes and Their Lambs

“…Lamb birth weights were within the physiological range for the Lacaune breed (3.90 ± 0.7 and 4.6 ± 0.2 for female and male lambs, respectively) [62,63]. Males were slightly heavier than females at birth, consistent with previous work [64], but this difference disappeared 17 days later.…”

Invited review: Current production trends, farm structures, and economics of the dairy sheep and goat sectors

“…Despite the large commercial demand for sheep-milk cheeses in the United States, the country has not succeeded in developing an important dairy sheep industry. Several attempts have been made to develop the US industry by importing East Friesian and Lacaune sheep and semen in 1993 and 1998, respectively, and Awassi later (Meisegeier, 2013;Thomas et al, 2014;Karras, 2017). However, the US dairy sheep industry is still very small and, so far, there are no organizations for the recording of pedigrees and performances for dairy sheep in the country.…”

The influence of lamb rearing system on ewe milk and lamb growth traits in dairy sheep

“…neighbouring countries. Highly productive ewes are able to produce more milk than suckling lambs need for their growth Thomas et al, 2014). However, rearing systems with lambs enabled to suckle ewes either exclusively or partially prior to exclusive machine milking occur occasionally (Marnet and McKusick, 2001); in spite of fact that about 25 to 30% proportion of milk yield is produced during first 30 to 60 days of lactation (Folman et al, 1966;Dikmen et al, 2007).…”