A Nutritional Investigation of Major Feed Types and Feed Rations Used in Medium-Scale Dairy Production Systems in Sri Lanka

• Published in: Animals (Basel) 2022-09, Vol.12 (18), p.2391
• Main Authors: Kumara, Sagara N., Parkinson, Tim J., Laven, Richard A., Waghorn, Garry C., Pushpakumara, Anil, Donaghy, Daniel J.
• Format: Article
• Language: English
• Subjects: Agriculture; Animal lactation; Availability; Carbon monoxide; Cattle; Cattle feeds; Chemical composition; Corn; Cow's milk; cows; Dairy cattle; Dairy farming; Dairy farms; Diet; Digestibility; Dry matter; energy; Energy requirements; Farmers; Feeds; forages; Gliricidia sepium; Grasses; Investigations; Laboratories; Lactation; Legumes; Livestock; Milk; Milk production; Nutritional requirements; Nutritive value; Panicum maximum; Pennisetum americanum; Pennisetum purpureum; protein; Proteins; Rations; tropical dairy farming; Zea mays
• ISSN: 2076-2615; 2076-2615
• DOI: 10.3390/ani12182391

In this paper, the nutritional quality, digestibility, and chemical composition of major feed types as well as the use of those feeds in rations by medium-scale dairy farmers in the Kurunegala district of Sri Lanka were studied. Nine dairy farms were visited fortnightly over a five-month period to identify the feeds that were commonly used. All farms operated under a stall-feeding system in which a manually mixed ration (MMR) was fed 2–3 times daily. Four forages were identified: Guinea grass ecotype A (Panicum maximum), called Guinea grass; Hybrid Napier CO-3 (Pennisetum purpureum × Pennisetum americanum), called CO-3 grass; Gliricidia (Gliricidia sepium); and maize stover (Zea mays L.), along with three other supplementary feeds (maize silage, barley distillers’ by-products, and commercially formulated cattle feed). These feeds were subjected to proximate analysis and in vitro digestibility analysis. The metabolisable energy (ME) of the forages ranged from 7.5–10.0 MJ/kg dry matter (DM), with the ME of Guinea grass and CO-3 grass (7.5 and 8.0 MJ/kg DM, respectively) being lower than that of Gliricidia (10.0 MJ/kg DM). The neutral detergent fibre (NDF) concentration of both Guinea grass and CO-3 grass (both 72% DM) was much higher than that of Gliricidia (47% DM). Crude protein (CP) was higher in Gliricidia (17.5% DM) than in either Guinea grass or CO-3 grass (8.0 and 8.8% DM, respectively). The ME of the supplementary feeds varied between 11.0 and 12.8 MJ/kg DM, while CP varied between 15.0 and 24.0% DM. The daily ME intake of cows was consistently 10% lower than their calculated daily energy requirement; for dry cows, the mean intake was 90 MJ/cow/day supplied vs. 101 MJ required, while for cows in early lactation the mean intake was 126 MJ/cow/day supplied vs. 140 MJ required. The average CP intake of lactating cows (13.5% DM) was inadequate (requirements: 16 to 17.5% DM), while the average CP intake of dry cows (11.8% DM) was satisfactory (requirements: 11 to 12% DM). The current study shows that the majority of the feed types used in these medium-scale dairy farms provide insufficient ME or CP to meet the nutritional requirements of either lactating or dry cows irrespective of the quantity of feed provided.