Ventura-Cordero, J. | bioRxiv Science

bioRxiv2023

Nutritional characterisation and seasonal variation of goat forages in Central Malawi

Goat ownership is prevalent across rural Malawi and provides a vital source of income, nutrition, and food security. However, goat performance is poor, and this presents a risk to individuals and communities who depend on them. Whilst mitigating this through supplementation of persevered forages may be possible, this is a challenge due to limitations of resources and the fact that goats typically free-roam during the dry season. Nutrition is fundamental to health and productivity of any livestock enterprise, it is required to be able to deal with stresses, such as disease, and to enable growth and production. The aim of this study was to characterise the nutritional profile of naturally available forages in Malawi, including the seasonal variation in nutrition. Samples of herbaceous forages and browse were collected over a 17-month period, across four villages (30 farms/smallholders) in Central Malawi. Forages underwent nutritional analysis for crude protein, fibre fractions, and ash/organic matter and NDVI obtained from satellite imagery was used as a measure of forage availability. Forage nutrition and availability were most adequate in the wet season, with higher concentrations of crude protein and a greater availability of herbaceous plants. There were significant differences in low-digestibility fibre fractions between locations, likely due to local factors such as soil and hydrology. The fall in crude protein concentrations from the wet season to the dry season represent a seasonal nutrition-gap which may result in risks to goat health and productivity.

zoology↗

bioRxiv2023

Opportunities to improve goat production and food security in Botswana through forage nutrition and the use of supplemental feeds

Goats fulfil a central role in food security across Africa with over half of households owning or rearing goats in rural areas. However, goat performance is poor and mortality high. This study assessed the nutritional quality of commonly used feeds and proposes feed-baskets to enhance goat nutrition and health. Feeds were collected from 11 areas within the Central District of Botswana, and macronutrient analyses were conducted, including crude protein, fibre fractions, ash, and metabolizable energy (ME). Forage nutrition was compared across seasons and soil types. Additionally, seasonal supplementation trials were conducted to evaluate consumption rates of various supplements, including crop residues, pellets, Lablab purpureus, and Dichrostachys cinerea. Each supplement was provided ad libitum for a 24-hour period, and consumption rates determined. Findings revealed significant differences in nutrition among various feed sources, across seasons, and in relation to soil types (p < 0.001). Consumption rates of supplements were higher during the dry season, possibly due to reduced forage availability. Supplement consumption rates varied across supplements, with crop residues accounting for approximately 1% of dry matter intake, compared to up to 45% for pellets, 13% for L. purpureus, and 15% for D. cinerea. While wet season feed baskets exhibited higher ME values compared to dry-season feed-baskets, the relative impact of supplementation was more pronounced during the dry season. These results highlight the potential for optimizing goat diets through improved grazing and browsing management, especially during the reduced nutritional availability in the dry season.

zoology↗