ABSTRACT

In two separate experiments, the replacement value of tiger nut meal (TNM) for maize offal was evaluated. The experiments were subjected to 4X4 Latin Square Design using four goats per experiment. ln the first experiment, nutrient digestibility and apparent nitrogen utilization by West African dwarf (WAD) bucks were evaluated while the second experiment was a lactation study involving WAD does. Four dietary treatments designated Tl, T2, T3 and T4 were formulated to contain 0, 30; l 0, 20; 20, IO and 30, O percentages of maize offal and TNM respectively. The bucks and does averaged 11.0kg and 14.5kg live weights respectively. The results showed that the diets; Tl, T2, T3 and T4 contained 14.35, 13.58, 13.31 and 13.33 % CP and 1.74, 1.70, 1.73 and 1.73 MJ/kg of energy respectively. Except ether extract, all the nutrients evaluated for apparent digestibility did not differ (P>0.05) statistically. Increasing levels of TNM promoted higher ether extract digestibility (P<0.05). Ether extract digestibility values ranged from 48.97- 69.82%. The apparent nitrogen (N) utilization study showed that all the parameters evaluated were statistically unaffected (P>0.05) by the treatments. Dry matter intake (DMI) was within the range of 2.85- 3.07% of live weight. Performance evaluation of the WAD docs showed non-significant (P>0.05) effect of diets. Milk yield (g/d) ranged from 68.52- 132.55. Apart from solids-not fat (SNF)(%) and fat-corrected milk (FCM)(g), all the milk constituents studied were influenced statistically (P<0.05) by the diets. Total solids (TS) were recorded highest in T4 while Tl had the highest milk protein. TS ranged from 12.37- 14.80% while 4.33 4.81% were recorded for milk protein. Butter fat percentage varied (P><0.05) statistically across the treatments. Increasing levels of TNM promoted higher butterfat percentage with a range ol 3.99 = 5.83 from TI- T4. Ash and lactose contents of milk were all influenced similarly by diets with ranges of 0.92- 1.03% and 4.26- 4.80% respectively. Solids-corrected milk (SCM, g) ranged from 98.90- 121.34 while milk energy (MJ/kg) recorded a range of 3.50- 4.33. Butterfat and SNF appeared to have great effect on the milk energy. From the results, it could be>deduced that tiger nut has great potential to improve milk yield and composition as well as overall animal performance if properly harnessed. It is recommended that TNM should replace maize off al up to 30% in the concentrate diet for lactating does for maximum yield and quality of milk.