Sixty dairy Damascus goats were used to study the effect of cereal grain source (barley versus corn grain) and of frequency of concentrate allocation (once versus thrice daily) on the lactation performance. Neither source of cereal grain (milk yield: corn 1.87kg per day, barley 1.82kg per day; fat content: corn 43.7g/kg, barley 46.6g/kg) nor frequency of feeding (milk yield: feeding once daily 1.87kg per day, feeding thrice daily 1.82kg per day; fat content: feeding once daily 44.7g/kg, feeding thrice daily 45.3g/kg) had an effect on milk yield, milk composition and liveweight changes of Damascus goats. The in situ effective degradability (measured on three rumen-fistulated Damascus goats) of dry matter (barley 55.4%, corn 40.9%), organic matter (barley 55.7%, corn 40.5%) and crude protein (barley 49.9%, corn 31.6%) of corn grain was lower than that of barley grain. Digestive upsets, as indicated by the number of animals suffered from diarrhea were more (five versus zero) in the barley than the corn mixture, and might be associated to the more rapid fermentation in the rumen of barley than corn grain. It is concluded that concentrate mixtures of corn or barley grain can attain similar milk yields and milk composition when fed to dairy goats, and that at high concentrate diets, barley, but not corn grain, may result in digestive upsets. Finally, increasing the numbers of daily concentrate meals (once versus thrice) does not affect milk yield and composition.
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