Page 7 - Effects of dried citrus pulp on nutrient intake, nitrogen balance and growth performance in Lohi lambs

INTRODUCTION

A tremendous increase in the population of Pakistan has elevated the demand of

grains, consequently increasing the competition between humans and animals for grains

and other food sources, which has resulted in higher prices of concentrate. Most of the
livestock farmers are unable to feed concentrate to their animals to fulfill their requirements

which is adversely affecting performance of their animal. In this situation, there is demand
for exploring cheaper non-conventional feed resources that can replace concentrate sources,

especially grains.

Different agro-industrial by-products especially fruit wastes are used mainly as an

energy source for feeding livestock (Crickenberger, 1991). Citrus pulp is an important by-

product obtained after extraction of juice from the citrus fruit. A large quantity of pulp is
produced which is not commonly fed to animals and causes disposal problems as well as

environmental pollution (Intrigliolo et al., 2001; Ralphs et al., 1995). It consists of peels,

inside residue and culled fruits (Mirzaei-Aghsaghali and Maheri-Sis, 2008). Citrus pulp can
be used as cereal grain replacer in the diet of ruminants on fresh basis. Fresh whole citrus

pulp is 49.2 to 69.2 % of the fresh citrus fruit (Martinez and Fernandez 1980). According
to NRC (1996), it contains about 82% total digestible nutrients (TDN) but its crude protein

(CP) is 6.7% which is considered as poor for animal feeding. However, due to high
transportation cost, perishability and seasonal availability, its use on fresh basis is limited.

By proper conservation, citrus pulp can be used in the diet of ruminant animals throughout

the year without any chemical change (Caparra et al., 2007). It can be conserved by drying
(dehydration) or ensiling (Bueno et al., 2002). However, handling and transportation of

dried citrus pulp is easy as compared to wet form (Arthington et al., 2002).

Dried citrus pulp has high nutritive profile. It is a concentrate source (Arthington et

al., 2002) which contains 120 to 400g sugar and less than 10g starch per kg of DM (Hall,

2000). It also contains 250g pectin contents per kg of DM which are approximately 98%
digestible (Arthington et al., 2002). Ruminal bacteria can easily degrade the pectin content

of dried citrus pulp (Sunvold et al., 1995). It can be used as an energy source to replace
grains (Al Khawajah, 2003; Barrios-Urdaneta et al., 2003; Caparra et al., 2007;

Crickenberger, 1991; Gado et al., 2009; Strobel and Russell, 1986). Addition of dried citrus

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