Whole-crop triticale silage for dairy cows grazing perennial ryegrass (Lolium perenne) or tall fescue (Lolium arundinaceum) pastures in small-scale dairy systems during the dry season in the highlands of Mexico.

Abstract

The dry season in central Mexico is a difficult time for small-scale dairy systems to meet feed requirements for their herds as pasture growth is limited. Conserved forage options are needed to complement pastures. The objective was to assess on-farm the production of dairy cows complemented with triticale silage (X. Triticosecale Witt. (TSL)) at two levels of inclusion (5.0 and 7.5kg DM/d), grazing pastures of two grass species during the dry season: perennial ryegrass (PRG; Lolium perenne) or tall fescue (TFC; Lolium arundinaceum) (TFC) with white clover (Trifolium repens), and 4.65kg DM/d concentrate. Experimental design was a 2× 2 factorial in repeated 4 × 4 Latin squares. Chemical composition of TSL was 96g CP/kg DM, 667g NDF/kg DM, 713g in vitro enzymatic digestibility of OM (IVEDOM)/kg DM, and pH of 4.6. There were differences (P< 0.05) in net herbage accumulation (NHA) and sward height between pastures, with higher NHA in TFC than that in PRG, although the chemical composition of PRG was higher (P< 0.05) in PC, IVEDOM, and estimated ME. There were no differences (P> 0.05) in milk yield (12.3 ± 2.63kg/cow/day), milk compositions (33.1 ± 0.45g milkfat/kg, 41 33.3 ± 0.21g milk protein/kg, 47.9 ± 0.36g lactose/kg, and 10.47 ± 2.25mg MUN/dL), body condition score (2.4 ± 0.22), or live weight (490 ± 72.8kg). At a higher inclusion of TSL, there was lower intake of pasture. Inclusion of 5.0kg DM/cow/day of triticale silage better complements grazing and sustains moderate milk yields when pasture growth and intake are limited.