Open AccessDOI
Comparison of models for describing the lactation curves of Chios sheep using daily records obtained from an automatic milking system
Maria Karangeli,Z. Abas,Theodoros Koutroumanidis,Chrisovalantis Malesios,Costas Giannakopoulos +4 more
- pp 571-589
TLDR
Wood model (1967) has a greater advantage of producing a good fit measurement with only three parameters and the model by Djikstra (1997) mechanist based and with a higher number of parameters showed a low convergence for the data used.Abstract:
The objectives of this study were: (i) to compare five models (Wood, Cobby & Le Du, Wilmink, Cappio Borlino, Djikstra) for describing the lactation curve of Chios sheep, (ii) to identify variation in lactation parameters related to environmental factors (season) and animal factors (parity). A data base on 61,705 recordings of daily milk production obtained from an automatic milking system was used. The lactation models were individually adjusted for each lactation. Analysis of variance was performed for the comparison of the parameter estimates. The goodness of fit measures used for comparisons of the models was the coefficient of determination (R), mean of mean square error (MMSE), Akaike information criterion (AIC), corrected Akaike information criterion (AICc) and Bayesian information criterion (BIC). Wood model had the lowest values for information criteria (MMSE = 347.4681, AIC = 1,056.436, AICc = 1,056.733, BIC = 1,063.856) and the highest value for the coefficient of determination (R=0.79). The highest values for information criteria were found for Djikstra’s model (MMSE = 636.6438, AIC = 1,076.621, AICc = 1,077.117, BIC = 1,086.582) having the same time the lowest value for the coefficient of determination (R=0.59). Overall, Wood (1967) model showed the best adjustment. Despite of being more recent, the model by Djikstra (1997) mechanist based and with a higher number of parameters showed a low convergence for the data used. Wood model (1967) has a greater advantage of producing a good fit measurement with only three parameters.read more
Citations
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Journal ArticleDOI
Goat Milk Nutritional Quality Software-Automatized Individual Curve Model Fitting, Shape Parameters Calculation and Bayesian Flexibility Criteria Comparison.
María Gabriela Pizarro Inostroza,Francisco Javier Navas González,Vincenzo Landi,José Manuel León Jurado,Juan Vicente Delgado Bermejo,Javier Fernández Álvarez,María Del Amparo Martínez Martínez +6 more
TL;DR: AlISCH and PARYLDENS can be used to study goat milk composition genetic variability as trustable evaluation models to face future challenges of the goat dairy industry.
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Optimization and Validation of a Linear Appraisal Scoring System for Milk Production-Linked Zoometric Traits in Murciano-Granadina Dairy Goats and Bucks
J. Fernández Álvarez,J.M. León Jurado,Francisco Javier Navas González,Carlos Iglesias Pastrana,J.V. Delgado-Bermejo +4 more
TL;DR: Model fit, variability explanation power and predictive power suggest the model comprising zoometric LAS scores performs better than traditional zoometry, and optimized reduced models are able to capture variability for dairy-related zoometric traits without noticeable detrimental effects on model validity properties.
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Camel Genetic Resources Conservation through Tourism: A Key Sociocultural Approach of Camelback Leisure Riding
Carlos Iglesias Pastrana,Francisco Javier Navas González,Elena Ciani,Sergio Nogales Baena,Juan Vicente Delgado Bermejo +4 more
TL;DR: The present research was intended to outline what are the social and cultural factors that can act as tourism attractions and satisfaction conditioning elements within this particular tourism enterprise and assessed the motivational factors affecting participation, satisfaction, and loyalty in this tourism segment.
Journal ArticleDOI
Comparison of the fit of automatic milking system and test-day records with the use of lactation curves.
TL;DR: Results show that lactation curves constructed from data derived from the AMS were better adjusted to the actual milk yield data regardless of the lactation number and model, and the Wilmink model was closer to the real values than the Wood model.
Journal ArticleDOI
Age-related linear and nonlinear modelling of semen quality parameters in Miranda donkeys
TL;DR: The aim of the present study was to model the gonadosomatic index and the quantitative and qualitative seminal parameters along age in Miranda donkeys, and found cubic function modelling reported the best-fitting properties for almost all variables, except for sperm concentration (exponential model).
References
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Journal ArticleDOI
Factors Affecting the Shape of Lactation Curves of Holstein Cows from the Balikesir Province of Turkey
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