Academic Journal

Predicting CO2 production of lactating dairy cows from animal, dietary, and production traits using an international dataset

التفاصيل البيبلوغرافية
العنوان: Predicting CO2 production of lactating dairy cows from animal, dietary, and production traits using an international dataset
المؤلفون: M. H Kjeldsen, M. Johansen, M.R. Weisbjerg, A.L.F. Hellwing, A. Bannink, S. Colombini, L. Crompton, J. Dijkstra, M. Eugène, A. Guinguina, A.N. Hristov, P. Huhtanen, A. Jonker, M. Kreuzer, B. Kuhla, C. Martin, P.J. Moate, P. Niu, N. Peiren, C. Reynolds, S.R.O. Williams, P. Lund
المصدر: Journal of Dairy Science, Vol 107, Iss 9, Pp 6771-6784 (2024)
بيانات النشر: Elsevier, 2024.
سنة النشر: 2024
المجموعة: LCC:Dairy processing. Dairy products
مصطلحات موضوعية: tracer gas, cattle, heat production, model evaluation, Dairy processing. Dairy products, SF250.5-275, Dairying, SF221-250
الوصف: ABSTRACT: Automated measurements of the ratio of concentrations of methane and carbon dioxide, [CH4]:[CO2], in breath from individual animals (the so-called “sniffer technique”) and estimated CO2 production can be used to estimate CH4 production, provided that CO2 production can be reliably calculated. This would allow CH4 production from individual cows to be estimated in large cohorts of cows, whereby ranking of cows according to their CH4 production might become possible and their values could be used for breeding of low CH4-emitting animals. Estimates of CO2 production are typically based on predictions of heat production, which can be calculated from body weight (BW), energy-corrected milk yield, and days of pregnancy. The objectives of the present study were to develop predictions of CO2 production directly from milk production, dietary, and animal variables, and furthermore to develop different models to be used for different scenarios, depending on available data. An international dataset with 2,244 records from individual lactating cows including CO2 production and associated traits, as dry matter intake (DMI), diet composition, BW, milk production and composition, days in milk, and days pregnant, was compiled to constitute the training dataset. Research location and experiment nested within research location were included as random intercepts. The method of CO2 production measurement (respiration chamber [RC] or GreenFeed [GF]) was confounded with research location, and therefore excluded from the model. In total, 3 models were developed based on the current training dataset: model 1 (“best model”), where all significant traits were included; model 2 (“on-farm model”), where DMI was excluded; and model 3 (“reduced on-farm model”), where both DMI and BW were excluded. Evaluation on test dat sets with either RC data (n = 103), GF data without additives (n = 478), or GF data only including observations where nitrate, 3-nitrooxypropanol (3-NOP), or a combination of nitrate and 3-NOP were fed to the cows (GF+: n = 295), showed good precision of the 3 models, illustrated by low slope bias both in absolute values (−0.22 to 0.097) and in percentage (0.049 to 4.89) of mean square error (MSE). However, the mean bias (MB) indicated systematic overprediction and underprediction of CO2 production when the models were evaluated on the GF and the RC test datasets, respectively. To address this bias, the 3 models were evaluated on a modified test dataset, where the CO2 production (g/d) was adjusted by subtracting (where measurements were obtained by RC) or adding absolute MB (where measurements were obtained by GF) from evaluation of the specific model on RC, GF, and GF+ test datasets. With this modification, the absolute values of MB and MB as percentage of MSE became negligible. In conclusion, the 3 models were precise in predicting CO2 production from lactating dairy cows.
نوع الوثيقة: article
وصف الملف: electronic resource
اللغة: English
تدمد: 0022-0302
Relation: http://www.sciencedirect.com/science/article/pii/S0022030224007847; https://doaj.org/toc/0022-0302
DOI: 10.3168/jds.2023-24414
URL الوصول: https://doaj.org/article/b677e8fd9f844de79d163cdb6a2a3c41
رقم الانضمام: edsdoj.b677e8fd9f844de79d163cdb6a2a3c41
قاعدة البيانات: Directory of Open Access Journals
الوصف
تدمد:00220302
DOI:10.3168/jds.2023-24414