**5. Effect of rumen-inert fat supplementation on the voluntary consumption**

Salvador *et al.* (2009) reported that there were not significant differences between groups in terms of voluntary consumption of food. Both groups consumed the whole dose of concentrate (200 g with 18% of crude protein) across the lactation period. Also, there were no differences (P > 0.05) in terms of consumption of hay of Bermuda grass (*Cynodon dactylon*) offered ad libitum between groups (0.85 ± 0.02 kg and 0.83 ± 0.02 kg for treatment and control group respectively). These results are consistent with those reported by Teh *et al*. (1994), González and Bas (2002) and Sanz Sampelayo *et al*. (2002a).

Figure 4 shows that there was a significant effect (P < 0.05) of days in milk on the consumption of hay, showing that hay consumption increased immediately after the peak of lactation and decreased as the milk production reduces, coinciding with results reported by Jimeno *et al*. (2003) who pointes out that the lowest level of consumption is just one week before calving. On the other hand, the voluntary consumption increased after calving up to the maximum consumption between 6 to 10 weeks; However, it was not linear increase. Then, subsequent to the peak of milk the consumption declined linearly as the milk production decreased.

**Figure 4.** Effect of rumen-inert fat on the voluntary consumption of hay in crossbreed Canarian goats during lactation.

Regarding to the consumption of the of rumen-inert fat (80 g) by goats in the treated group, there was no rejection of the fat, consuming all the by-pass offered.

Results showed that the addition of this type of rumen-inert fat has no a substitute effect of the main component of the diet of ruminants (grass) but works as a supplement, thereby improving the quality of the diet, reducing the NEB, and improving the productive and reproductive parameters.
