Italian Journal of Animal Science (Jan 2010)

Feeding behaviour, digestibility, energy balance and productive performance of lactating goats fed forage-based and forage-free diets

  • Gianni Matteo Crovetto,
  • Alberto Tamburini,
  • Luciana Bava,
  • Luca Rapetti

DOI
https://doi.org/10.4081/ijas.2005.71
Journal volume & issue
Vol. 4, no. 1
pp. 71 – 83

Abstract

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Six lactating Saanen goats have been used in a Latin Square design to evaluate a grass-based diet (G), a hay-based diet(H) and a nonforage diet (NF). On dry matter, grass and hay contributed for 55% of the diets and had 13.7 and 16.1%CP, 55.4 and 49.4% NDF, 38.0 and 31.6% ADF, respectively. Diet NF had beet pulp, cracked carob beans and whole cottonseedas main ingredients, with more than 75% of the particles greater than 2 mm.Independently of the dietary treatment, the goats spent more time eating than ruminating. Diet NF proved to be effectivein stimulating chewing activity, despite a trend for a lower chewing activity for eating (178, 185, 125 min/kg DMIfor diets G, H and NF, respectively), but not for ruminating (84, 80, 80 min/kg DMI for diets G, H and NF, respectively).Feed intake did not differ among diets, while regarding digestibility diet NF had the highest values for DM (74.1%), OM(75.7%) and non-fibrous carbohydrates (92.0%), but the lowest for ADF (44.5%). For treatments G, H and NF milk yieldswere 3011, 3688 and 3212 g/d (P2.96% (Pml, PC18:0, C18:1 and C18:3 in comparison to the other two diets. No difference among treatments was recorded for CLA.Intake energy was digested to a lesser extent for diet G (68.9, 70.0, 72.7%, Pquality forage. Urinary energy losses reflected the corresponding protein contents of the diets, while no difference wasrecorded for methane production. ME resulted higher for diet NF (60.0, 60.7, 65.1% of the intake energy, Pheat production and milk energy yield were similar in the three treatments. Diet NF had a higher ME content (11.13,11.26, 11.93 MJ/kg DM, P0.69) and NEl (7.20, 7.93, 8.30 MJ/kg DM).It is concluded from the study that a nonforage diet with an adequate amount of structured fibre could substitute a rationbased on poor quality forage in lactating goats; however, good forage seems to enhance milk performance to a greaterextent.

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