Production of small ruminants such as ram and goats, play a significant role in the food chain and overall livelihoods of rural households. The production of ruminants such as ram is mainly based on a low-input traditional extensive system where animals are supplemented on agricultural waste e.g. Corn, corn cob, peels of cassava, yam, plantain and cocoyam which are not always available in adequate amounts resulting in low levels of productivity (reduced growth and reproductive performance) and loss of animals especially lambs (Baiden and Obese, 2010). Therefore, there is a need for conservation and improvement of the nutritive values of such agricultural waste because inadequate nutrition is one of the main causes of low ruminant production in Nigeria. Agricultural waste is increasingly being viewed as a valuable resource though they are usually fibrous, with poor quality nutrients which make their digestibility low.
In Nigeria there are more than 21 million tonnes of plant by-products produced annually, among them is the corn crop residues which include; green corn, corn Stover, corn stalk and corncobs (Fajemisin et al., 2012). Biochemically treated corncob silage meal is a high-quality feed that contains a high concentration of energy, protein and some mineral elements. Silage can be an economical source of nutrients for sheep and goats, especially on large farms where feeding can be mechanized (Susan, 2009). The use of urea or ammonia, lye solution and poultry litter to upgrade the nutritive value of straws and other low quality crop residues have been world wide spread in the last three decades (Chineke et al., 2013). Urea and poultry litter are the most commonly used. Inexpensive non-protein nitrogen (NPN) is alternative source and attractive protein replacement compared with nowadays tremendously expensive natural proteins. Using lye solution, urea and poultry litter to upgrade the nutritive value of corncobs could help to enhance the use of corncobs as protein rich resources for small ruminants during dry season and feed scarcity. Also, using corncobs in animal feeding would help in reducing environmental pollution from burnt corncobs.
Over the years, the increasing demand for food and sustenance of food security by the rapidly growing human population led to intensification of more farm land for crop production. This situation resulted to abundance of crop residues, which are left on the field following harvest or farm level processing. Corncob and cassava peel are crop residues obtained during processing of maize and cassava after harvesting from the field. They are available in large quantities and could be utilized as feedstuffs during periods of acute fodder shortage for ruminant in small holder farming systems in South Western parts of Nigeria. Although, corncob are of low digestibility due to its high ligno-cellulose contents (Chineke et al., 2013), however, they are important source of energy in ruminant feeding. Improved performance have been reported (Fajemisin et al. 2012) for West African Dwarf goats and N’dama heifers fed corncob in compounded ration. In the same vein, cassava peel (a by-product of tuber processing) is widely used as an important energy feed in ruminant diets or as energy supplement to forage in ruminant feeding. Depending on the variety, cassava peel is low in protein content but high in fiber, fermentable carbohydrates, and is rapidly or well degraded in the rumen (Adegbola et al., 2010). Although, cassava peel is well relished by ruminants, the concentration of hydrocyanic acid, which is approximately 623 ppm (Uza et al., 2005) could be harmful except they are reduced to a level not harmful to the animals either by oven drying, sun drying or ensiling.
Moreover, feed intake and nutrients digestibility in ruminant occur in a sequential process, digestion in ruminants occurs sequentially in a four-chambered stomach. Plant material is initially taken into the Rumen, where it is processed mechanically and exposed to bacteria than can break down cellulose (foregut fermentation). The Reticulum allows the animal to regurgitate & reprocess particulate matter ("chew its cud"). More finely-divided food is then passed to the Omasum, for further mechanical processing. The mass is finally passed to the true stomach, the Abomasum, where the digestive enzyme lysozyme breaks down the bacteria so as to release nutrients. Use of plant material is thus indirect, with primary processing by the bacterial flora maintained in the stomach. Nutrients absorbed from the digestive tract include volatile fatty acids, amino acids, fatty acids, glucose, minerals, and vitamins. These are used in the synthesis of the many different compounds found in meat, and wool, and to replace nutrients used for maintaining life processes including reproduction. Digestion begins when an animal takes a bite from the pasture. The rate of digestibility of straw depends on the rate and extent of colonisation of fibre and the biomass of adherent organisms (Okolo et al., 2012) and the high digestibility forage supplement may act to seed microbes onto the less digestible straw. It has been reported (Adegbola, 2002) that poor quality roughages fed to ruminants without supplementation during the dry season caused considerable weight losses and finally the death of the animal. The prices of conventional sources of protein in livestock ration have risen exorbitantly (Susan, 2009) and this has necessitated the search for cheap alternative feed materials that can meet nutritional requirements of farm animals.
Corncob serve as a cheap and alternative dietary protein supplement that can provide fermentable nitrogen in order to ensure an adequate level of ammonia nitrogen within the rumen and release of nitrogen to support biological activities. Despite its dietary protein content, corncob is also known to have a low nutritive quality which brought about the incorporation of Cassava peel and poultry dropping to the corncob in order to boost its nutritive content. Corncob, cassava peel and poultry dropping silages could be diet for sustainable ruminant production during periods of acute fodder shortage since it consist of poultry dropping which could be harnessed as alternative nitrogen supplement to reduce the cost of feed production and enhanced optimal performance of WAD rams (Leo et al., 2009). The use of locally available feed resources such corncob and cassava peel gotten from crop residues can be used to improve ruminant production systems and more importantly, dietary supplements of nitrogen sources that will enhance feed intake and utilization by ruminant fed poor roughage diets.
- General Objective
The general objective of this research work is to evaluate the feed intake and nutrients digestibility of wad ram fed corncob, cassava peel and poultry droppings silage.
- Specific Objectives
- To determine the chemical composition of corn cob, cassava peel and poultry dropping.
- To determine nutrient digestibility of corn cob, poultry dropping.
iii. To determine the level of feed intake by the WAD ram.