Feed intake, growth rate and some anatomical characteristics of broilers fed commercial diets supplemented with green feeds

A study was conducted on the Teaching and Research Farm of the Rivers State University of Science and Technology, Nigeria to evaluate the nutritional suitability of four treatments, namely a commercial type broiler diet as compared with the commercial diet supplemented with either fresh centrosema (Centrosema molle), pueraria (Pueraria phaseoloides), or waterleaf (Talinium triangulare) leaves. These diets were fed to 120 day-old chicks (Lohmann Brown) over a 62-day period with treatments arranged in a completely randomized design (CRD). Chemical composition of broiler basal diets differed significantly from the three green foliage supplements. Dry matter (DM) of leaf meals ranged from 97.8 to 227.0 g kg-1 which was significantly (P<0.05) lower than that of broiler basal diets which averaged 900 g kg-1. Crude protein (CP) of leaf meals, however, ranged from 182.0 to 244.0 g kg-1 which was generally higher than basal diets (130-153 g kg-1). Similarly, crude fiber (CF) was highest for centrosema and pueraria leaves (330-342 g kg-1) and lowest in basal diets (164-222 g kg-1). However, ether extract (EE) and nitrogen-free extract (NFE) were significantly higher in broiler basal diets. Broiler daily and total feed intake over 62 days were similar between treatments and the control, averaging 112 g d-1, while diets containing waterleaf were slightly (2.5%) lower. Total and daily bodyweight (BW) gains (2110 g and 34 g d-1) were also similar between treatments and the control, except that gains where the broiler diet was supplemented with centrosema foliage were 2.9% higher. A higher feed conversion ratio (FCR) and lower protein efficiency ratio (PER) for the diet supplemented with pueraria indicates a higher feed efficiency and better protein efficiency in the commercial control diet. Carcass characteristics with the commercial control diet included greater (P<0.05) intestinal length and gizzard and spleen weights than with green foliage supplements. However, broiler carcass weight was generally lowest (P<0.05) in the control group (64.3 g/100 g BW) and highest in the waterleaf group (71.3 g/100 g BW). Small differences in carcass weight among the treatments tested reduces the effectiveness of green feeds for practical and economic intensive broiler production. However, increased effectiveness of green feed supplementation for broiler production might likely be observed where broilers are managed on fenced rangelands planted to selected green feeds or in integrated systems where other livestock (rabbits, sheep, goats, etc.) are jointly reared. These results support the recommendation that leaf meals of green feeds should be incorporated into broiler diets in future studies.