Effect of crabgrass (Digitaria ciliaris) hay harvest interval on forage quality and performance of growing calves fed mixed diets1

Abstract

Twelve 0.81-ha crabgrass (Digitaria ciliaris [Retz.] Koel.) hay fields were harvested at 21, 35, and 49 d of regrowth (average phonological growth stage of 30, 51, and 56, respectively). Increased harvest interval exhibited a linear decrease (P < 0.01) in CP (14.1, 13.7, and 10.6% of DM, respectively) and increase (P < 0.01) in NDF (65.3, 70.6, and 70.2% of DM, respectively) and ADF (35.7, 38.9, and 42.7% of DM, respectively). Hays were incorporated into 3 diets that contained 20% (DM basis) crabgrass hay, ground corn (33%), and soybean hulls (32%). Diets contained 14.4, 14.4, and 13.6% CP; 1.83, 1.72, and 1.81 Mcal of NE(m)/kg; and 1.21, 1.10, and 1.17 Mcal of NE(g)/kg; respectively. Diets were fed to beef calves in 12 pens at a rate of 2.3% (DM basis) of BW in 1 experiment (n = 120, initial BW 210 +/- 4.4 kg) and ad libitum in another experiment (n = 60, initial BW 207 +/- 4.4 kg). To measure passage rate of the hay and concentrate portions of the diets, 12 heifer calves (BW = 145 +/- 4.5 kg) were individually fed at 2.3% of BW for 14 d and dosed with Dy-labeled soybean hulls and Yb-labeled hay. In situ DM digestibility of the hays and diets were determined using 3 ruminally cannulated steers (BW = 584 +/- 10.4 kg). Harvest interval did not affect (P > or = 0.11) ADG of limit-fed calves during the diet acclimation or growing phases (average 0.32 and 0.80 kg, respectively) or ADG of calves fed ad libitum (average 1.21 kg). Dry matter intake of calves fed ad libitum averaged 7.9 kg/d (3.28% of BW) and was not affected (P > or = 0.22) by harvest interval. Gain:feed was not affected (P > or = 0.20) by harvest interval (0.13 and 0.15 for limit-fed and ad libitum-fed calves, respectively). Increased harvest interval linearly increased (P < 0.01) ruminal retention time of the hay and tended (P = 0.06) to linearly increase ruminal retention time of the concentrate portions of the diet. Harvest interval linearly decreased (P < or = 0.05) the extent of degradability and effective degradability of DM and NDF of hays, but DM disappearance of the total diet did not differ (P > or = 0.35). In the conditions of this study, increasing harvest interval of crabgrass hay from 21 to 49 d had no deleterious impact on animal performance or efficiency of gain when fed to growing calves in a high-concentrate mixture.

Influence of Height‐Based Management on Forage Nutritive Value of Four Warm‐Season Forage Grasses

“…Neither ADF nor NDF differed among cuttings until 3 wk post cutting, at which the first cut had lower ADF and NDF amounts and greater NDFD amounts than second cut (Table 5). These results support the statements of Dalrymple et al (1999) as well as the results of Teutsch et al (2005) and Beck et al (2015) indicating that crabgrass produces forage of high nutritive value throughout the growing season with appropriate nitrogen fertilization, appropriate harvest intervals, and adequate moisture.…”

“…In all species, the observed ranges of CP, ADF, NDF, and NDFD were comparable to those recorded in other experiments (Bosworth et al, 1980; Griffin and Jung, 1983; Vona et al, 1984; Teutsch et al, 2005; Starks et. al., 2006; Beck et al, 2015 Burns and Fisher, 2008; Temu et al, 2014; Gelley et al, 2016). It was expected that nutritive value would differ among cuts of each species, with earlier cuts producing herbage with higher nutritive value than later cuts when the samples were compared at similar stages of maturity (weeks postcutting) (Tables 2, 3, 4, and 5).…”

Effect of brown midrib gene and maturity at harvest on forage yield and nutritive quality of sudangrass

“…hay fields harvested at 21, 35 and 49 days of regrowth (average phenologic growth stage of 30, 51 and 56, respectively; Beck et al . ). There was a significant BMR by roughage concentration interaction ( P < 0.01) for diet DM intake per steer (Table ).…”

Harvest Management Effects on Canopy Height and Light Interception of ‘Performer’ Switchgrass and its Relationship with Weed Infestation

“…(Fig. However, crabgrass has greater nutritive value and is readily grazed by livestock compared with most other warm-season grasses (Beck et al, 2007). Fig.…”