Chitin ranks next to cellulose as the most important bio-polysaccharide which can primarily be extracted from crustacean shells. However, the emergence of new areas of the application of chitin and its derivatives are on the increase and there is growing demand for new chitin sources. In this study, therefore, an attempt was made to extract chitin from the house cricket (Brachytrupes portentosus) by a chemical method. The physicochemical properties of chitin and chitosan extracted from crickets were compared with commercial chitin and chitosan extracted from shrimps, in terms of proximate analysis in particular, of their ash and moisture content. Also, infrared spectroscopy, x-ray diffraction (XRD), scanning electron microscopy and elemental analysis were conducted. The chitin and chitosan yield of the house cricket ranges over 4.3%-7.1% and 2.4%-5.8% respectively. Chitin and chitosan from crickets compares favourably with those extracted from shrimps, and were found to exhibit some similarities. The result shows that cricket and shrimp chitin and chitosan have the same degree of acetylation and degree of deacetylation of 108.1% and 80.5% respectively, following Fourier transform infrared spectroscopy. The characteristic XRD strong/sharp peaks of 9.4 and 19.4° for α-chitin are common for both cricket and shrimp chitin. The percentage ash content of chitin and chitosan extracted from B. portentosus is 1%, which is lower than that obtained from shrimp products. Therefore, cricket chitin and chitosan can be said to be of better quality and of purer form than commercially produced chitin and chitosan from shrimp. Based on the quality of the product, chitin and chitosan isolated from B. portentosus can replace commercial chitin and chitosan in terms of utilization and applications. Therefore, B. portentosus is a promising alternative source of chitin and chitosan.

No abstract

In the present work six metals (Cu, Pb, Zn, Cd, Mn and Ni) were analyzed for, using atomic absorption spectrophotometry in three main feed brands commonly used in Sokoto (2 commercial feed and 1 locally compounded chicken feed). Initially, the samples were digested with concentrated nitric acid and perchloric acid at about 3700C to 4500C heat in a digestion block. The concentration in ìg/ml of the six metals analyzed for in the feed samples ranged between 0.04 and 1.21 for Cu, 0.01 and 0.55 for Pb, 1.43 and 11.65 for Zn, 0.10 and 0.12 Cd, 0.94 and 3.12 for Mn and 0.004 and 0.25 for Ni. In most of the analyzed samples, the concentration of Cu, Zn, Mn and Ni was found to be lower than the nutritional requirement of broiler chicken at a level which could be harmful for the poultry. Also the study showed the presence of heavy metals (Pb and Cd) in all the feed samples analyzed, but none exceeded permissible levels as set by European Union and National Research Council.Keywords: Atomic absorption spectrophotometry, Chicken feeds, Contamination, Heavy metals, Sokoto, Toxicity

Majority of the studies on the effect of chitin and chitosan on growth and carcass characteristics of broiler chickens has concentrated more on shrimp chitin and shrimp chitosan, and often with contradictory results. Therefore, the objective of this present study is to evaluate and compare the effect of dietary chitin and chitosan from cricket and shrimp on growth performance, carcass, and organ characteristics of broiler chickens. One hundred fifty-day-old male Cobb500 broiler chicks of similar average weight were randomly allotted into one of the five dietary treatments with three replicates. Treatment 1 (T1) chicks were fed basal diet only (control), treatment 2 and 3 (T2 and T3) chicks were given basal diet with 0.5 g/kg diet of cricket chitin and cricket chitosan, respectively, while treatment 4 and 5 (T4 and T5) chicks were served basal diet with 0.5 g/kg diet of shrimp chitin and shrimp chitosan respectively. No significant variation occurred between cricket chitin and shrimp chitin, although data on growth performance were higher in cricket chitin, but growth performance varied significantly between cricket chitosan and shrimp chitosan. This study revealed that cricket chitin at 0.5 g/ kg significantly improved growth performance, carcass quality, and organ characteristics of broilers more than chitosan. Birds fed basal diet alone, although gained more weight, also accumulated more fat having the poorest feed conversion ratio (FCR) and the highest mortality. However, carcass of birds fed cricket chitin was the leanest and thus economically beneficial as they consumed the least amount of feed with the best FCR.