Fresh citrus pulp is palatable to cattle but may require some adaptation, and storing (one or two weeks storage have been reported) to maximise feed intake. The higher palatability may be due to changes in the citrus pulp rather than to an adaptation of the cows (Crawshaw, 2004). Citrus pulp can be fed fresh or as silage to ruminants. Mature cattle accustomed to this, assuming 20% DM as quoted above, will consume 6-10 kg DM/day (Göhl, 1978). Intakes of 11 kg/day citrus press cake silage have been reported for mature cows in Florida (Becker et al., 1946).
As stated above, fresh or ensiled citrus pulp, as all citrus by-products, have an unbalanced Ca:P ratio that may cause milk fever in cattle at, or soon after, parturition (Bath et al., 1980 cited by Bampidis et al., 2006).
Fresh citrus pulp silage offered to crossbred dairy cows fed ad libitum on a restricted tropical pasture/concentrate (0.5 kg) based diet resulted in lower milk yield (6.4 kg/cow/day vs. 7.3 kg/cow/day) but did not alter milk quality (Montejo et al., 2008).
Crossbred cull cows (380-428 kg live weight) grazing poor quality winter tropical native grassland and supplemented with 15 kg/day of fresh citrus pulp (about 2 kg DM) for 3-4 months had higher daily weight gains than unsupplemented cows (352-612 g/d vs. 73-372 g/d) (Navamuel et al., 2002; Coppo et al., 2003). Under similar conditions, fresh citrus pulp supplementation of younger animals (220 kg) did not improve weight gain during a 3-month period (Coppo et al., 2006). In Cuba, fattening bulls fed on ensiled citrus pulp, hay and concentrate gained 633 g/day/head (Ojeda Garcia, 2010).
Fresh citrus pulp can replace 30% lucerne hay in late gestation and post-lambing ewes, because it enhances total diet digestibility and decreases consumption, without deleterious effects on lamb growth, wool production or ewe live weight (Sparkes et al., 2010). Fresh citrus pulp included at 70% in a silage mixture had no effect on milk production or milk composition but increased fat content (6.85% vs. 5.85% ) when offered to primiparous dairy ewes in late lactation (Volanis et al., 2006).
Pressed citrus pulp can replace up to 75% corn silage in a fattening diet for lambs without any effect on growth or carcass composition. The higher daily weight gain is obtained with 50% replacement of the corn silage (Pereira et al., 2008).
A silage mixture of 80% fresh citrus pulp and 20% wheat straw, with 70% of the concentrate normally offered to lambs in an oat hay/concentrate based diet, resulted in lower concentrate intake and had no effect on daily weight gain or dressing percentage. Citrus silage gave better carcass conformation and less carcass fatness and proved to be economically interesting for lamb production (Scerra et al., 2001).
Fresh citrus pulp included at up to 30% of the diet can replace lupin seeds in an alfalfa chaff-based diet for wethers without altering intake, daily weight gain and wool quality (Fung et al., 2010).