Supplementation of dairy cows with commercial concentrate or ground maize grain under cut-and-carry or grazing of cultivated pastures in small-scale systems in the highlands of central Mexico

Abstract

Small-scale dairy systems (SSDS) in Mexico represent over 78% of dairy farms and 37% of milk production. In the central highlands, many SSDS base the feeding of herds on irrigated cultivated pastures (mostly cut-and-carry), straws, and large amounts of commercial concentrates that result in high feeding costs and low economic sustainability. Intensive grazing may result in lower feeding costs when compared with cut-and-carry strategies. The high protein content of pasture may meet requirements of dairy cows with moderate milk yield (16–20 kg milk/cow.day), so that lower protein supplements, like ground maize grain, may substitute for commercial concentrates. An on-farm experiment following a participatory rural research approach was undertaken with seven farmers evaluating commercial concentrate (CC) or ground maize grain (MG) as supplement; and two pasture managements, grazing (G) or cut-and-carry (C) of irrigated ryegrass/white clover pastures to assess productive performance and feeding costs. Six farmers participated with four milking cows each and one farmer with two groups of four milking cows in a 2 by 2 factorial experiment. Daily milk yield per cow before the experiment was used as covariate. The experiment lasted 12 weeks. There is a trend in G for higher protein content in milk (P < 0.10). CC showed higher body condition score than MG with a significant interaction for body condition score with the highest body condition score in CCC (P < 0.05). Feeding costs were 15% higher per kg of milk yield and 19% per kg of energy-corrected milk under cut-and-carry but no statistical differences were detected (P > 0.05) in comparison with the grazing strategy. Supplementing with home-grown ground maize grain resulted in 28.5% higher margins per kg of milk produced. Implementing grazing involves less work burden for small-scale dairy farmers, and combined with home-grown grains as supplement is a viable option that may reduce feeding costs in these systems.

Feeding Forage Mixtures of Ryegrass (Lolium spp.) with Clover (Trifolium spp.) Supplemented with Local Feed Diets to Reduce Enteric Methane Emission Efficiency in Small-Scale Dairy Systems: A Simulated Study

“…To determine the diet specifications, the following variables were kept constant: live weight (LW), days of lactation, milk yield, and chemical composition ( Table 2 ) in all treatments. The data were obtained from previous research studies in the region [ 8 , 9 , 30 , 31 ]. Briefly, samples of pastures (red clover (RC) ( Trifolium pratense) with perennial ryegrass ( Lolium perenne ) and white clover (WC) ( Trifolium repens ) with annual ryegrass ( Lolium multiflorum ), commercial concentrate, ground maize grains (GMG), and wet distillers’ grains (WDG), were dried in a forced-air oven at 60 °C for 48 h. Once dried, they were ground with a Wiley mill (2.0 mm screen; Arthur H. Thomas, Philadelphia, PA, USA) and analyzed in duplicates for DM (930.15) and nitrogen (N; 990.02) using the Association of Official Analytical Chemists (AOAC) [ 32 ] standard methods.…”

“…In vitro dry matter digestibility (IVDMD) was performed of each ingredient by the Ankom–Daiy method [ 17 , 34 ]. Other details on diet preparation, including the control and supplementation strategies, were described previously [ 8 , 9 , 30 , 31 ].…”

“…The chemical composition of feeds was obtained from information collected for previous research studies in the region during the dry season [ 9 , 30 ] and rainy season [ 8 , 31 ]; missing data were obtained using data from the National Research Council (NRC) [ 35 ] and the Institut National de la Recherche Agronomique (INRA) [ 36 ]. The diets were formulated using two pasture management strategies (M): grazing of cultivated pastures (G), which has been a successful technology adopted by farmers to reduce feeding costs [ 30 ], and cut-and-carry (C), a conventional feeding strategy used by the SSDS [ 31 ]. The two pasture management strategies (G and C) were composed of different clover varieties (Var): RC ( Trifolium pratense ) with perennial ryegrass ( Lolium perenne ) and WC ( Trifolium repens ) with annual ryegrass ( Lolium multiflorum ).…”

“…In vitro dry matter digestibility (IVDMD) was performed of each ingredient by the Ankom-Daiy method [17,34]. Other details on diet preparation, including the control and supplementation strategies, were described previously [8,9,30,31]. Dairy production is one of the main activities in Aculco, State of Mexico, where 82% of milk is destined for artisanal cheese production.…”

The Mode of Grass Supply to Dairy Cows Impacts on Fatty Acid and Antioxidant Profile of Milk

“…However, not all animals have the possibility of grazing, either due to lack of available surface or due to handling difficulties. Thus many farmers have to adopt a cut-and-carry system or provide preserved grass to the manger [ 26 , 27 ].…”