Effects of stage of maturity at harvest of cereal crops on biomass and quality, estimated forage dry matter intake, beef cow performance, and system economics

Abstract

The objective of this study was to evaluate the effects of maturity at harvest of cereal crops on biomass, quality, cow performance, and economics. In each of 3 yr, a 48-ha field was divided into 3 paddocks (16 ha per treatment) and seeded to either barley (Hordeum vulgare CDC Maverick, 135 kg/ha), oat (Avena sativa CDC 29 SO1, 135 kg/ha), or triticale (Triticosecale Taza, 135 kg/ha). Half of each field (8 ha) was swathed at either soft dough (SDo) or hard dough (HDo) stage for grazing. Each year, 120 dry pregnant beef cows (631 kg) were randomly allocated to 1 of 6 replicated (n = 2) paddocks for 90, 106, and 88 d in yr 1, 2, and 3, respectively. Triticale had 19 and 23% greater total yield than oat and barley, respectively. Barley CP was greater (P < 0.05; 10.9%) than oat (9.3%) or triticale (9.8%) at HDo stage. The animal unit months (AUM) per hectare were greater for HDo (11.5 ± 0.8 AUM/ha) than SDo (9.15 ± 0.8 AUM/ha) stage. Cow ADG was greater (P = 0.01) for barley (0.61 kg/d) compared with triticale (0.39 kg/d). Total crop cost averaged Can$426, Can$437, and Can$458/ha for oat, barley, and triticale, respectively. The HDo stage had Can$0.40 lower dollars per cow per day in-field costs (P = 0.02) than the SDo stage and 10% (Can$26.25 per cow/d) lower feeding costs (P = 0.02) over 3 yr. Delaying harvest to hard dough can increase yield and reduce feeding costs without affecting cow performance.