Taxonomic and nutritive validation of fodder grasses of central Punjab, Pakistan

Abstract

The grasses have acquired a sufficient scientific attention and belong to largest plant family (Poaceae). The world’s dry land is enclosed about one-third by the Poaceae members and a great number of people rely profoundly on cereal grasses. Moreover this is predominantly true for the grasses that they are the part of exclusive animal feed as well. Fertile plain of Central Punjab Pakistan is rich with fodder grasses and from centuries the local inhabitants of this area have been using their regional grasses for ruminant feeding. However little or no information was available about the nutritional potential of these ethnobotanically used grasses. Moreover grasses always faced difficulties in identification because of their more or less identical leaf shapes, indefinite variations in stem branching pattern and reduced floral parts. Hence this study took an initiative to establish a nutritive data bank of these ethnobotanically used fodder grasses along with provision of taxonomically viable tools for their identification. Data regarding ethnobotanically used grass fodder species was collected by using snowball technique to identify key informants, whereas semistructured questionnaires, face-to-face interviews and site visits were used for describing the fodder grasses. For taxonomic evaluation classical taxonomic parameters (morphological, anatomical and palynological) were employed. In order to develop a nutritional profile proximate analysis (moisture, dry matter, ash, organic matter, crude proteins, fats, neutral and acid detergent fibre, lignin, cellulose, hemicellulose) and anti-nutritional analysis (total phenols, total tannins, condensed tannins) in combination to mineral and digestibility analysis were determined. Besides their nutritional evaluation, the legitimacy of ethnobotanical knowledge of local inhabitants of Central Punjab Pakistan about these fodder grasses was also verified. Data analysis was done by using SPSS 22 software. This software was used for descriptive statistics and interpretation of associations among studied parameters. Microsoft Excel was used to present data as % values and graphs. Overall results reported 53 fodder grasses which were grouped into high (A), medium (B) and low priority (C) groups. Group A grasses were reported as not only the most abundant but also the most palatable forages to all types of ruminants. Taxonomic data provided some valuable identification tools whereas nutritional results suggested that majority (77%) of these fodder grasses can be regarded as good quality fodders because of their high protein (up to 169g/kg) and digestible nutrients with low fibre (≤ 601.65g/kg), lignin (≤ 50.24 g/kg) and anti-nutrients (total phenols ≤ 87.32 g/kg, total tannins ≤ 77.81 g/kg, condensed tannins ≤ 61.23 g/kg). A positive relationship was identified between ethnobotanical knowledge and nutritional results for certain fodder grasses. Spearman correlation showed that ranking of species based on ethnobotanical preferences was highly correlated with the laboratory results of individual grass species with ‘r’ values for CP (0.85), NDF (-0.76), ADF (-0.72) and ADL (-0.62). The resilient complementarities between ethnobotanical preferences and nutritive analysis suggested the incorporation of these ethnobotanically used fodders into modern ruminant feeding system. These findings are significant for appropriate fodder selection and development of supplements for the sustainable and economically viable livestock industry.