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developing alternative feeds for goats and for proper
feeding practices that enhance gain or production
effi ciency.
The newly revised book, Nutrient Requirements of
Sheep, Goats, Cervides and Camelids (NRC, 2007), has
relied in part on the information from sheep and cattle,
except for energy and protein requirements of goats. The
Small Ruminant Committee of the National Research
Council, of which the senior author was a part, faced
tremendous challenges to accomplish the task due to the
lack of published information on the basic science of goats,
especially vitamins and minerals. It should be noted that
the majority of the information may exist but it is not
properly reported.
Goat nutrition research has received much less attention
when compared with the amount of similar research for
sheep and cattle (Table 19.1). There is a need for basic and
fundamental studies to address factors infl uencing nutrient
requirements of goats and factors such as genotype, sex,
environment, and physiological processes responsible for
their metabolic effi ciency. Future research should address
and quantify the energy and protein requirements among
sexes. Energy expenditure in grazing and browsing or even
in confi nement of goats is not fully understood. Goats are
very social animals and spend more time playing and
socializing. This may justify additional energy require-
ments for such activities. Future research should address
the impact of restricted protein and energy feeding prior
to refeeding on tissue accretion and body weight gain as
affected by prior body condition score of the goat.
Is the commonly acceptable minimum digestible dry
matter of 65% in the diet of cattle suffi cient to allow
adequate intake for growth and productivity in goats? Also
browse selectivity and level of intake are poorly investi-
gated in goats. Another area that is practically ignored is
information on particulate and fl uid passage rates and their
effects on intake and microbial fermentation in goats.
Trace mineral requirements of goats are different from
other species; however, many of the goat requirements are
using data from sheep and cattle. As was indicated based
on literature searches, this area of nutrition has received
the least attention after vitamin research. Trace minerals
play an important role in an animal's metabolism, besides
protein and energy metabolism and immune responses.
Trace mineral supplements designed for cattle and recom-
mended based on requirements and level of intake by cattle
may be misleading when used for goats. Future research
should focus on more refi ned prediction of intake for goats
for mineral supplements and total dry matter intake. Goats
have a stronger sense of taste and may have different
preferences for salty or sweet feeds than cattle or sheep.
Trace mineral supplements designed for cattle assume pro-
portional intake based on salt level, but goats may have
different intake. More research should be focused on taste
preferences of goats as well as their requirements to enable
nutritionists to design proper diets, salt blocks, and trace
mineral mixes appropriate for goat intake to avoid defi -
ciency or toxicity. Studies on vitamin requirements for
goats are hard to fi nd even if available.
Goat Reproduction
According to the database search of reported literature,
there is less research conducted on goat reproduction than
for sheep or cattle. Certain areas of goat reproduction have
been researched less when compared to sheep and cattle
reproduction; however, this area has received more atten-
tion when compared with other areas of research in goats.
With newly introduced goat breeds and composites, more
research is justifi ed to reconnect and confi rm validity and
applicability of the collected and reported data. Research
is needed that could be used and extend as a tool in genetic
improvement of goats including semen and embryo cryo-
preservation, embryo sexing, and the use of artifi cial
insemination to improve production in goats.
Table 19.2
Continued
1
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MEDLINE and other life science journals for biomedical articles back to 1948. PubMed includes links to full text
articles and other related resources.
2
PubMed Central (PMC) is the U.S. National Institutes of Health's (NIH) free digital archive of biomedical and life
sciences journal literature.
3
USDA covers all United States Department of Agriculture databases.
4
Agricola is a bibliographic database of citations to the agricultural literature created by the National Agricultural
Library and its cooperators.
5
Google is the most popular search engine on the Web.
