The effect of wide swathing on wilting times and nutritive value of alfalfa haylage

Abstract

On 3 consecutive cuttings, alfalfa from a single field was mowed with a John Deere 946 mower-conditioner (4-m cut width; Moline, IL) to leave narrow swaths (NS) ranging from 1.2 to 1.52 m wide (30-37% of cutter bar width) and wide swaths (WS) ranging from 2.44 to 2.74 m wide (62-67% of cutter bar width). Samples were collected from windrows and dry matter (DM) was monitored during wilting until a target of 43 to 45% DM was obtained. Forage from random windrows (n=4-6) was harvested by hand, chopped through a forage harvester before being packed in replicated vacuum-sealed bags, and allowed to ensile for 65 d. There was no swath width x cutting interaction for any parameter tested. Over all cuttings, the resulting silage DM was not different between the NS silage (43.8%) and the WS silage (44.9%). However, wide swathing greatly reduced the time of wilting before making silage. The hours of wilting time needed to reach the targeted DM for the NS silage compared with the WS silage at cuttings 1, 2, and 3 were 50 versus 29, 54 versus 28, and 25 versus 6, respectively. At the time of ensiling, the WS silage had more water-soluble carbohydrates (5.1%) than did the NS silage (3.7%). The WS silage had a lower pH (4.58) than did the NS silage (4.66), but swath width did not affect fermentation end products (lactic acid, acetic acid, and ethanol). The NS silage had more NH(3)-N (0.26%) than did the WS silage (0.21%). Wide swathing did not affect the concentration of ash or the digestibility of NDF, but it lowered the N content (NS=3.45%; WS=3.23%) and increased the ADF content (NS=39.7%; WS=40.9%) of the resulting silage. Wide swathing can markedly reduce the time that alfalfa must wilt before it can be chopped for silage, but under good conditions, as in this study, the resulting silage quality was generally not improved.

Nonstructural Carbohydrate Concentration during Field Wilting of PM‐ and AM‐Cut Alfalfa

“…Wilting alfalfa in wide swaths reduced the drying time needed to reach 350 g DM kg −1 FM by 9 h (−28%) under slow wilting (i.e., the spring of 2008) and by 2 h (−18%) under fast drying conditions (i.e., the summer and autumn of 2008, and spring and summer of 2009). This result concurs with Kung et al (2010) who reported that the drying time to reach 350 g DM kg −1 FM was reduced by 3 to 4 h (11 to 50%) in wide swaths, resulting in greater NSC concentration compared with narrow swaths. Shinners and Herzmann (2006) with alfalfa and Wilkinson et al (1999) with perennial ryegrass reported similar results.…”

“…Drying phases for cut plants include: (i) rapid initial drying with water loss mostly by evapotranspiration through open stomata, (ii) a longer drying period with water loss through stem and leaf cuticle, and (iii) slow loss of the remaining tightly‐held water (Demarquilly, 1987; Moser, 1995). Allowing the forage to dry in wide swaths rather than in narrow swaths accelerates all three phases (Rotz, 1995; Wilkinson et al, 1999; Kung et al, 2010). Wilting conditions affect forage NSC concentration because metabolism remains active after cutting and depletes carbon reserves until dehydration reaches the point where respiration is impaired.…”

“…Although previous studies evaluated changes in NSC concentration during wilting [Alli et al (1985) in alfalfa and timothy; Trevino et al (1995) in oat ( Avena sativa L.)] relative to swath management [Wilkinson et al (1999) in perennial ryegrass ( Lolium perenne L.); Shinners and Herzmann (2006) and Kung et al (2010) in alfalfa], limited information is available for the changes in the NSC concentration following PM‐ and AM‐cutting. To establish management practices that favor high NSC concentration in forages, we monitored the changes in NSC concentration during field wilting of PM‐ and AM‐cut alfalfa for narrow and wide swaths.…”

Effects of dairy slurry on silage fermentation characteristics and nutritive value of alfalfa

“…Buffering capacity tended to be greater for forages receiving no slurry compared with slurry-applied forages (383 vs. 364 mEq/kg; P = 0.063), and for ideal compared with dry forages (380 vs. 357 mEq/kg; P = 0.065). Concentrations of WSC and starch were not affected (P ≥ 0.099) by slurry application or initial bale moisture, although the overall concentration of WSC in pre-ensiled HARV1 forages (7.2%) was greater than reported in other studies (Kiziksimsek et al, 2007;Schmidt et al, 2009;Kung et al, 2010), and may have been related to the drought conditions that became increasingly stressful for growing forage plants throughout the late July.…”

Clinical biochemistry profile of American Quarter Horse broodmares fed Tifton-85 (Cynodon spp.) hay and haylage

“…The purpose of this addition was to balance the microbial population in the material for haylage production, improving anaerobic fermentation. Approximately 1.3kg of green mass was wrapped in polyethylene bags (40 x 60cm) and vacuum sealed according to the technique described earlier (Kung Junior et al 2010). Diet composition is described in Table 1 and haylage composition is established in Table 2.…”