Construction of a predictive model for the 48-hour digestibility of neutral detergent fiber in forage

doi:10.11686/cyxb2024481

Abstract

Abstract:

Forage is the primary source of dietary fiber for ruminants. Neutral detergent fiber （NDF） is an important indicator used to measure the fiber content of roughage. Its digestibility is a key parameter for evaluating forage quality and animal dry matter intake. Currently， the in vitro 48-hour NDF digestibility （NDFD₄₈） is commonly used to assess forage NDF digestibility. An accurate measure of the NDFD₄₈ value of roughage is important for balancing animal diets. Presently， roughage NDFD₄₈ can be measured using the rumen nylon bag technique， laboratory semi-in vitro methods， or near-infrared spectroscopy， but these are often constrained by test conditions and unavailability of equipment. Given the biological significance of NDFD₄₈， this study aimed to develop a computational method to predict NDFD₄₈. Fiber indicators （NDF and acid detergent fiber， ADF） and digestibility indicators （NDFD₄₈） from NASEM （2021） were used as a test set to build the NDFD₄₈ model. Fourteen articles from the Journal of Dairy Science along with relevant indicators， and laboratory-measured values， were selected as two validation sets for the model. The results showed that the calculated NDFD₄₈ values were significantly correlated with the measured NDFD₄₈ values in the two validation sets （P<0.001）， with R2 values of 0.89 and 0.85， respectively. The model was further validated using the concordance correlation coefficient （CCC）， achieving CCC values of 0.93 and 0.91. This model requires fewer input indicators， is easy to compute， and demonstrates high accuracy. Based on the evaluation performed here， the model can provide forage NDF estimates suitable for production applications and forage nutrition prediction.

Key words: roughage, fiber digestibility, simplified algorithm

Yun-yi LIANG, Ya-kun CHEN, Ke-ke HE, Jia-yu YANG, Lian-sheng ZHAO, Deng-pan BU. Construction of a predictive model for the 48-hour digestibility of neutral detergent fiber in forage[J]. Acta Prataculturae Sinica, 2025, 34(11): 150-160.

Figures/Tables 12

References 45

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国际饲料编号International feed number	饲料名称 Feed name	酸性洗涤纤维ADF （%DM）	中性洗涤纤维NDF （%DM）	中性洗涤纤维48 h消化率NDFD₄₈ （%NDF）
NRC6F1	苜蓿草Alfalfa	33.9	42.9	49.1
NRC6F33	冷季草，成熟Cool season grass， mature	41.4	66.7	55.8
NRC6F34	冷季草，中熟Cool season grass， medium-mature	35.5	58.0	67.8
NRC6F89	禾豆混播干草Grass and legume mixed hay	39.3	58.2	54.5
NRC6F84	禾豆混播干草，禾为主，中熟Grass and legume mixed hay， grass dominant， medium-mature	33.8	54.7	67.5
NRC6F86	禾豆混播干草，豆为主，成熟Grass and legume mixed hay， legume dominant， mature	38.7	51.2	48.0
NRC6F91	豆科干草，未成熟Leguminous hay， immature	30.7	37.7	51.4
NRC6F92	豆科干草，成熟Leguminous hay， mature	37.2	46.6	43.4
NRC6F93	豆科干草，中熟Leguminous hay， medium-mature	32.1	41.1	52.4
NRC6F107	豌豆干草Pea hay	32.0	43.4	58.5
NRC6F109	稻草Rice straw	62.0	43.0	48.2
NRC6F110	谷草Millet straw	75.0	50.0	43.2
NRC6F111	玉米秸秆Corn stalks	70.8	46.7	49.3
NRC6F112	莜麦秸Hulless oat straw	74.0	49.0	44.4
NRC6F114	花生秧Peanut straw	37.9	45.8	40.1
NRC6F131	一年生黑麦草，中熟Annual ryegrass， medium-mature	36.7	57.3	59.8
NRC6F127	一年生黑麦草，成熟Annual ryegrass， mature	42.7	66.8	55.9
NRC6F138	高粱青干草Sorghum green hay	38.8	63.0	60.8
NRC6F142	苏丹草Sudan grass	39.3	61.0	54.4
NRC6F143	黄豆草Soybean grass	31.3	40.3	50.5
NRC6F151	苏丹草，成熟Sudan grass， mature	41.6	65.8	55.8
NRC6F152	苏丹草，中熟Sudan grass， medium-mature	36.9	54.6	56.7
NRC16F164	小黑麦干草Triticale hay	38.3	60.0	63.7
NRC16F176	小麦秸秆Wheat straw	53.1	76.9	41.8
NRC16F18	狗牙根青贮，成熟Bermudagrass silage， mature	42.8	70.8	52.3
NRC16F19	狗牙根青贮，中熟Bermudagrass silage， medium-mature	39.0	64.1	63.5
NRC16F35	冷季草青贮Cool season grass silage	39.0	62.1	63.6
NRC16F52	玉米秸秆，青贮，高干物质Corn stalks， silage， high dry matter	46.9	72.0	56.2
NRC16F51	玉米秸秆，青贮，低干物质Corn stalks， silage， low dry matter	44.8	66.2	52.8
NRC16F90	草豆混播青贮Grass and beans mixed silage	34.8	51.2	61.1
NRC16F88	禾豆混播青贮，豆为主Grass-legume mixed silage， legume-dominant	33.9	45.9	56.2
NRC16F95	豆科牧草青贮，中熟Leguminous forage silage， medium-mature	33.7	43.2	49.4
NRC16F100	粟黍青贮Foxtail millet silage	39.2	59.7	61.2
NRC16F106	燕麦青贮，中熟Oat silage， medium-mature	38.8	57.4	54.1
NRC16F108	豌豆青贮Pea silage	37.1	52.5	57.7
NRC16F121	水稻青贮，带穗Rice silage with panicles	31.8	41.9	54.2
NRC16F130	一年生黑麦草青贮，中熟Annual ryegrass silage， medium-mature	38.3	58.0	61.9
NRC16F135	饲用高粱青贮，未成熟Sorghum silage， immature	36.4	56.7	58.5
NRC16F136	饲用高粱青贮，成熟Sorghum silage， mature	39.2	61.6	63.6
NRC16F140	苏丹草青贮Sudan grass silage	38.9	59.5	54.9
NRC16F154	苏丹草青贮，中熟Sudan grass silage， medium-mature	39.0	60.7	64.6
NRC16F165	小黑麦豌豆混播青贮Triticale and pea mixed silage	37.1	55.7	65.1
NRC16F166	小黑麦青贮，成熟Triticale silage， mature	37.2	58.6	58.5
NRC16F167	小黑麦青贮，中熟Triticale silage， medium-mature	34.8	52.2	57.5
NRC16F174	小麦青贮，抽穗Wheat silage， heading stage	35.1	51.1	61.4
NRC16F175	小麦青贮，植株Wheat silage， plant	37.0	56.6	59.0

国际饲料编号International feed number	饲料名称 Feed name	酸性洗涤纤维ADF （%DM）	中性洗涤纤维NDF （%DM）	中性洗涤纤维48 h消化率NDFD₄₈ （%NDF）
NRC6F1	苜蓿草Alfalfa	33.9	42.9	49.1
NRC6F33	冷季草，成熟Cool season grass， mature	41.4	66.7	55.8
NRC6F34	冷季草，中熟Cool season grass， medium-mature	35.5	58.0	67.8
NRC6F89	禾豆混播干草Grass and legume mixed hay	39.3	58.2	54.5
NRC6F84	禾豆混播干草，禾为主，中熟Grass and legume mixed hay， grass dominant， medium-mature	33.8	54.7	67.5
NRC6F86	禾豆混播干草，豆为主，成熟Grass and legume mixed hay， legume dominant， mature	38.7	51.2	48.0
NRC6F91	豆科干草，未成熟Leguminous hay， immature	30.7	37.7	51.4
NRC6F92	豆科干草，成熟Leguminous hay， mature	37.2	46.6	43.4
NRC6F93	豆科干草，中熟Leguminous hay， medium-mature	32.1	41.1	52.4
NRC6F107	豌豆干草Pea hay	32.0	43.4	58.5
NRC6F109	稻草Rice straw	62.0	43.0	48.2
NRC6F110	谷草Millet straw	75.0	50.0	43.2
NRC6F111	玉米秸秆Corn stalks	70.8	46.7	49.3
NRC6F112	莜麦秸Hulless oat straw	74.0	49.0	44.4
NRC6F114	花生秧Peanut straw	37.9	45.8	40.1
NRC6F131	一年生黑麦草，中熟Annual ryegrass， medium-mature	36.7	57.3	59.8
NRC6F127	一年生黑麦草，成熟Annual ryegrass， mature	42.7	66.8	55.9
NRC6F138	高粱青干草Sorghum green hay	38.8	63.0	60.8
NRC6F142	苏丹草Sudan grass	39.3	61.0	54.4
NRC6F143	黄豆草Soybean grass	31.3	40.3	50.5
NRC6F151	苏丹草，成熟Sudan grass， mature	41.6	65.8	55.8
NRC6F152	苏丹草，中熟Sudan grass， medium-mature	36.9	54.6	56.7
NRC16F164	小黑麦干草Triticale hay	38.3	60.0	63.7
NRC16F176	小麦秸秆Wheat straw	53.1	76.9	41.8
NRC16F18	狗牙根青贮，成熟Bermudagrass silage， mature	42.8	70.8	52.3
NRC16F19	狗牙根青贮，中熟Bermudagrass silage， medium-mature	39.0	64.1	63.5
NRC16F35	冷季草青贮Cool season grass silage	39.0	62.1	63.6
NRC16F52	玉米秸秆，青贮，高干物质Corn stalks， silage， high dry matter	46.9	72.0	56.2
NRC16F51	玉米秸秆，青贮，低干物质Corn stalks， silage， low dry matter	44.8	66.2	52.8
NRC16F90	草豆混播青贮Grass and beans mixed silage	34.8	51.2	61.1
NRC16F88	禾豆混播青贮，豆为主Grass-legume mixed silage， legume-dominant	33.9	45.9	56.2
NRC16F95	豆科牧草青贮，中熟Leguminous forage silage， medium-mature	33.7	43.2	49.4
NRC16F100	粟黍青贮Foxtail millet silage	39.2	59.7	61.2
NRC16F106	燕麦青贮，中熟Oat silage， medium-mature	38.8	57.4	54.1
NRC16F108	豌豆青贮Pea silage	37.1	52.5	57.7
NRC16F121	水稻青贮，带穗Rice silage with panicles	31.8	41.9	54.2
NRC16F130	一年生黑麦草青贮，中熟Annual ryegrass silage， medium-mature	38.3	58.0	61.9
NRC16F135	饲用高粱青贮，未成熟Sorghum silage， immature	36.4	56.7	58.5
NRC16F136	饲用高粱青贮，成熟Sorghum silage， mature	39.2	61.6	63.6
NRC16F140	苏丹草青贮Sudan grass silage	38.9	59.5	54.9
NRC16F154	苏丹草青贮，中熟Sudan grass silage， medium-mature	39.0	60.7	64.6
NRC16F165	小黑麦豌豆混播青贮Triticale and pea mixed silage	37.1	55.7	65.1
NRC16F166	小黑麦青贮，成熟Triticale silage， mature	37.2	58.6	58.5
NRC16F167	小黑麦青贮，中熟Triticale silage， medium-mature	34.8	52.2	57.5
NRC16F174	小麦青贮，抽穗Wheat silage， heading stage	35.1	51.1	61.4
NRC16F175	小麦青贮，植株Wheat silage， plant	37.0	56.6	59.0

第一作者First author	发表时间Publication time	涉及饲草Forage
Oliver A L^［17］	2004	苜蓿干草、高粱青贮Alfalfa hay， sorghum silage
Dann H M^［18］	2008	高粱和苏丹草混合青贮Sorghum and sudan grass mixed silage
Kendall C^［3］	2009	小麦秸秆、苜蓿青贮Wheat straw， alfalfa silage
Colombini S^［2］	2012	高粱青贮Sorghum silage
Kammes K L^［19］	2012	苜蓿青贮、鸭茅青贮Alfalfa silage， duck grass silage
Brunette T^［20］	2016	混合牧草青贮Mixed forage silage
Coblentz W K^［21］	2013	燕麦草Oat grass
Palmonari A^［22］	2016	苜蓿、禾本科饲草Alfalfa， grass forage
Fustini M^［23］	2017	苜蓿干草Alfalfa hay
Brown A N^［24］	2018	黑麦草、小黑麦、大麦、毛苕子、三叶草Ryegrass， rye， barley， hairy roots， clover
Lyons S E^［25］	2019	饲用高粱草Sorghum grass
Krogstad K C^［26］	2021	苜蓿干草、小麦秸秆Alfalfa hay， wheat straw
Farhad P K^［27］	2023	黑麦草、牛茅草、红三叶草、白三叶草Ryegrass， fescue， red clover， white clover
Stypinski J D^［28］	2024	苜蓿干草Alfalfa hay

第一作者First author	发表时间Publication time	涉及饲草Forage
Oliver A L^［17］	2004	苜蓿干草、高粱青贮Alfalfa hay， sorghum silage
Dann H M^［18］	2008	高粱和苏丹草混合青贮Sorghum and sudan grass mixed silage
Kendall C^［3］	2009	小麦秸秆、苜蓿青贮Wheat straw， alfalfa silage
Colombini S^［2］	2012	高粱青贮Sorghum silage
Kammes K L^［19］	2012	苜蓿青贮、鸭茅青贮Alfalfa silage， duck grass silage
Brunette T^［20］	2016	混合牧草青贮Mixed forage silage
Coblentz W K^［21］	2013	燕麦草Oat grass
Palmonari A^［22］	2016	苜蓿、禾本科饲草Alfalfa， grass forage
Fustini M^［23］	2017	苜蓿干草Alfalfa hay
Brown A N^［24］	2018	黑麦草、小黑麦、大麦、毛苕子、三叶草Ryegrass， rye， barley， hairy roots， clover
Lyons S E^［25］	2019	饲用高粱草Sorghum grass
Krogstad K C^［26］	2021	苜蓿干草、小麦秸秆Alfalfa hay， wheat straw
Farhad P K^［27］	2023	黑麦草、牛茅草、红三叶草、白三叶草Ryegrass， fescue， red clover， white clover
Stypinski J D^［28］	2024	苜蓿干草Alfalfa hay

项目 Item	中性洗涤纤维NDF （%DM）		酸性洗涤纤维 ADF （%DM）		中性洗涤纤维48 h消化率 NDFD₄₈ （%NDF）
项目 Item	均值Mean	标准差SD	均值Mean	标准差SD	均值Mean	标准差SD
豆科Legume	41.25	3.96	30.64	4.05	59.10	17.63
禾豆混播Grasses and legume mixed forage	47.50	1.97	30.49	1.59	73.15	4.11
禾本科Grasses	58.36	5.91	37.25	5.48	59.87	10.63