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EFFECT OF GRADED LEVELS OF MEXICAN SUNFLOWER LEAF …
Introduction
Lactation plays an important role in the life of
sheep. Apart from provision of milk for humans,
lactation is an indication of good lamb performance.
Owen (1981) reported that the main difference in
lamb growth arising from lactation is due to
variation in the yield of milk. Poor quality feed
especially during the dry season has been identified
as one of the major constraints to small scale dairy
production (Barje et al., 1999).
In most animals not specialized for milk
production, the composition of milk is, apart from
vitamins, is largely independent of the quality of the
diets, any inadequacy or shortages being reflected
by a diminished yield (McDonald et al., 1987).
Sheep milk composition can also be influenced by
different feeds, grazing systems and by subclinical
mastitic conditions (Bufano et al., 1996). Milk
composition of major and minor components is
affected by feeding regimes, ration components and
forage : grain ratios (Perea et al., 2000). Studies by
Ekeocha et al., 2012 have shown that lactating West
African dwarf ewes fed on Mexican sunflower leaf
meal based diets have substantial mineral profile at
her disposal.
However, research emphasis worldwide has
been on sheep wool and meat production and their
characteristics, not on sheep milk.
Most textbooks on “Milk” deal only with cow
milk, and human milk to some extent (Kon and
Cowie, 1961; Falconer, 1971; Renner, 1982;
Gravert, 1983). The only major sources of research
information on sheep milk appear to be the bulletins
and proceedings of the International Dairy
Federation Seminars held in Greece in 1985 and
1995 (IDF, 1983; 1986; 1996). Not even the 1 st
World Congress of Dairy Products in Human
Health and Nutrition (Serrano Rios, 1994)
recognized the existence or contribution of sheep
milk products to human nutrition, nor does the
handbook of the US Sheep Industry Development
Program (Scott, 1986). In France, the scientific
journal Le Lait devoted an entire issue to goat milk,
including its role as an alternative to cow milk (Le
Lait, 1993). A biobliography on goat milk (Freund,
2000), and the proceedings of a national colloquium
on the nutritional and dietetic qualities of goat milk
(Freund, 1996) have been published, but similar
efforts on sheep milk are still missing. Even a book
on buffalo milk is available (Deepak Sahai, 1996).
Searching the CAB for the past 10 years, the
numbers of publications worldwide on sheep milk,
sheep cheese and allergies related to sheep milk are
minor compared to those on cow milk (King, 1988).
Certainly there are more publications in earlier
years, but those would be based on less
sophisticated analytical methods. Publications on
the nutritional value of sheep milk often give only
gross composition without detailed identification of
more specific unique components of benefit in
human nutrition, although trade magazines contain
many anecdotal reports that are waiting for
scientific evaluation. However, among the 1,000
research projects on sheep worldwide (King, 1988),
less than 4% deal with topics of sheep milk and
sheep dairying.
This experiment is aimed at evaluating feed
intake and weight change from WAD ewes fed
MSLM based diets during lactation.
Materials and Methods
Experimental Site
This study was carried out at the sheep unit of
the University of Ibadan Teaching and Research
farm.
Management of Experimental Animals
Sixteen WAD ewes aged between 16 - 17
months and weighing 19.50 – 22.46kg were used.
The management of experimental animals was same
as for the feeding trial.
Oestrus Synchronisation
Oestrus was artificially synchronized in all the
animals using Dinoprost tromethanine solution
PGF 2 -Tuco products, Canada),
administered intra-muscularly in two doses of 1ml
given 19 days apart. Rams bred at the sheep unit of
Teaching and Research farm were introduced once
signs of heat were detected. Mating was allowed
before 08.00hrs and after 18.00hrs to minimize heat
stress on the rams. All ewes were weighed at mating
and monthly thereafter till parturition and continued
till end of lactation.
728 J. Anim. Sci. Adv., 2012, 2(9):727-733