Effects of hybrid type, stage of maturity, and fermentation length on whole plant corn silage quality

İki farklı mısır silajı hibriti (Tane; T, Silajlık; S) erken sütlenme (ES), 72 sütlenme (72 S) ve siyah katman (SK) olgunluk derecelerinde hasat edilmiştir. Her bir hibrit ve olgunluk derecesindeki mısır silajları sırasıyla 0, 1,2, 4, 8, ve 16 haftalık sürelerde fermantasyona tabi tutulmuştur. Silaj kalite parametreleri sırasıyla pH, kuru madde (KM), ham protein (HP) ve ruminal in situ KM sindirilebilirliği olarak ölçülmüştür. Uzayan fermantasyon süresi optimum silaj pH değerini sağlamıştır (8 hafta = 3,97, 16 hafta = 3,93). Optimum silaj KM düzeyi her iki hibritte de ortalama olarak V2 S olgunluk derecesinde oluşmuştur (% 36,4). In situ KM sindirilebilirliği S hibritinde T hibritine göre % 4 daha yüksek gözlemlenmiştir. Mısır silajlarında, fermantasyon uzunluğu ile in situ KM sindirilebilirliği arasında bir ilişki gözlemlenmezken (r = 0,15), ES (% 48,4) ve 7Z S (% 42,8) olgunluk derecelerinde, SK (% 23,5) olgunluk derecesine göre daha yüksek ruminal in situ KM sindirilebilirliği gözlemlenmiştir. Optimum pH ve HP içerikleri mısır silajlarında en az 8 haftalık bir fermantasyon uzunluğunun olması gerektiğini göstermiştir. Kimyasal kompozisyon ve in situ KM sindirilebilirliği, optimum hasat olgunluğunun ES ve 72 S arasında olması gerektiğini göstermiştir.

Hibrit çeşidi, olgunluk derecesi ve fermantasyon uzunluğunun mısır silajı kalitesi üzerine etkileri

Two corn hybrids (conventional: CON; silage: SIL) were harvested at early dent (ED), 72 milkline (72 ML), and black layer (BL) stages of maturity for testing the effects of hybrid, stage of maturity, and length of fermentation on corn silage quality. Tested parameters were pH, DM, CP, and ruminal in situ DM disappearance (ISDMD), respectively. Longer fermentation length caused lower silage pH at 8 (3.97) and 16 (3.93) weeks. While CP content tended to increase with longer fermentation length, it tended to decrease with increasing maturity stage (ED: 8.0%; BL: 7.2%). In situ DM disappearance was 4% higher for the SIL hybrid compared to CON hybrid (40.1% vs. 36.2%). Higher ISDMD was observed for ED (48.4%) and 72 ML (42.8%) maturity stages compared to the BL maturity stage (23.5%). In conclusion, similar chemical composition, but higher ISDMD favored the SIL hybrid over CON hybrid. Based on chemical composition and ISDMD, the optimum harvesting stage in whole plant corn silage should be between ED and 72 ML. In addition, for optimal pH, fermentation length should be between 8 and 16 weeks in whole plant corn silage.

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1. Coors, J.G., Laurer, J.G.: Silage Corn. In: Hallauer, A.R., Ed. Specialty Corns. 2nd ed. CRC Press Inc., Boca Raton, Florida. 2001:347-392.3.
2. Johnson, L.M., Harrison, J.H., Davidson, D., Robutti, J.L., Swift, M., Mahanna, W.C., Shinners, K.: Corn silage management I: Effects of hybrid, maturity, and mechanical processing on chemical and physical characteristics. J. Dairy Sci., 2002; 85: 833-853.
3. Bal, M.A., Coors, J.G., Shaver, R.D.: Impact of the maturity of corn for use as silage in the diets of dairy cows on intake, digestion, and milk production. J. Dairy Sci., 1997; 80: 2497-2503.
4. Hunt, C.W., Kezar, W., Vinande, R.: Yield, chemical composition, and ruminal fermentability of corn whole plant, ear, and stover as affected by hybrid. J. Prod. Agric, 1992; 5: 286-290.
5. Russell, J.R.: Influence of harvest date on the nutritive value and ensiling characteristics of maize stover. Anim. Feed Sci. Technol., 1986:14:11-27.
6. Fisher, D.S., Burns, J.C.: Quality analysis of summer-annual forages II. Effects of forage carbohydrate constituents on silage fermentation. Argon. J., 1987; 79: 242-248.
7. AOAC: Official Methods of Analysis. 15th ed. Association of Official Analytical Chemists, Washington, DC. i 990.
8. Cherney, D.J.R., Patterson, J.A., Lemenager, R.P.: Influence of in situ bag rinsing technique on determination of dry matter disappearance. J. Dairy Sci., 1990; 73: 391-397.
9. SAS: SAS User's Guide: Statistics, Version 6.03 Edition. SAS Inst, Inc., Cary, NC. 1988.
10. Bal, M.A., Shaver, R.D., Shinners, K.J, Coors, J.G., Lauer, J.G., Straub, R.J., Koegel, R.G.: Stage of maturity, processing, and hybrid effects on ruminal in situ disappearance of whole plant corn silage. Anim. Feed Sci. Technol., 2000; 86: 83-94.
11. Xu, S., Harrison, J.H., Kezar, W., Entrikin, N., Loney, K.A., Riley, R.E.: Evaluation of yield, quality, and plant composition of early- maturing corn hybrids harvested at three stages of maturity. J. Prof. Anim. Sci., 1995; 11: 157-165.
12. Weiss, W.P., Wyatt, D.J.: Effect of oil content and kernel processing of corn silage on digestibility and milk production by dairy cows. J. Dairy Sci., 2000; 83: 351-358.
13. Kuehn, C.S., Linn, J.G., Johnson, D.G., Jung, H.G., Endres, M.I.: Effect of feeding silages from corn hybrids selected for leafiness or grain to lactating dairy cattle. J. Dairy Sci., 1999; 82: 2746-2755.
14. Dwyer, L.M., Andrews, C.J., Stewart, D.W., Ma, B.L., Dugas, J.A.: Carbohydrate levels in field-grown leafy and normal maize genotypes. Crop Sci., 1995; 35: 1020-1027.
15. Hunt, C.W., Kezar, W., Vinande, R.: Yield, chemical composition, and ruminal fermentability of corn whole plant, ear, and stover as affected by maturity. J. Prod. Agric, 1989; 2: 357-361.
16. Argillier, 0., Hebert, Y., Barriere, Y.: Relationships between biomass yield, grain production, lodging susceptibility and feeding value in silage maize. Maydica, 1995; 40: 125-136.
17. Wiersma, D.W., Carter, P.R., Albrecht, K.A., Coors, J.G.: Kernel milkline stage and corn forage yield, quality, and dry matter content. J. Prod. Agric, 1993; 6: 94-99.
18. Lin, C, Bolsen, K.K., Brent, B.E., Fung, D.Y.C.: Epiphytic lactic acid bacteria succession during the pre-ensiling and ensiling periods of alfalfa and maize. J. Appl. Bacteriol., 1992; 73: 375- 387.