A bio-economic model to improve profitability in a large national beef cattle population

A bio-economic model was developed for estimating economic values for use in improving profitability in a large national beef cattle population from birth to slaughter. Results were divided into fattening costs, production costs and income. Economic values were derived for 17 traits for two regions, mature weight (-0.43 € and -0.38 €/+1 kg of live weight), age at first calving (-0.13 € and -0.11 €/+1d), calving interval (-1.06 € and -1.02 €/+1d), age at last calving (0.03 € and 0.03 €/+1d), mortality 0-48 h (-5.86 € and -5.63 €/1% calves per cow and year), pre-weaning mortality (-5.96 € and -5.73 €/+1% calves per cow and year), fattening mortality (-8.23 € and -7.88 €/+1% calves per cow and year), adult mortality (-8.92 € and -7.34 €/+1% adult cows per cow and year), pre-weaning average daily gain (2.56 € and 2.84 €/+10g/d), fattening young animals average daily gain (2.65 € and 3.00 €/+10g/d), culled cow in fattening average daily gain (0.25 € and 0.16 €/+10g/d), culled cow dressing carcass percentage (3.09 € and 2.42 €/+1%), culled cow price (4.59 € and 3.59 €/+0.06 €/kg), carcass conformation score (16.39 € and 15.3 €/+1 SEUROP class), dressing carcass rate of calf (18.22 € and 18.23 €/+1%), carcass growth (9.00 € and 10.09 €/+10g of carcass weight/d) and age at slaughter (0.27 € and 0.44 €/+1d). Two sample herds were used to show the economic impact of calving interval and age at first calving shortening in the profit per slaughtered young animal, which was 178 € and 111 € for Herds A and B, respectively. The economic values of functional traits were reduced and production traits were enhanced when fertility traits were improved. The model could be applied in a Spanish national program

Clinical mastitis in Spanish dairy cows: incidence and costs

Clinical mastitis in Spanish dairy herds has been studied. Since April 2005 up to December 2006, in 25 Spanish herds 1,054 cases registered were available. Aims were to determine mastitis incidence and factors of risk, to analyze whether yield production has been affected, and to quantify mastitis costs along 2006. The 25% lactations were infected at least once with average recurrence of 1.64. Descriptive analysis showed that 29% of cases occurred within the first month after calving. Primiparous showed higher mastitis frequency at early and late lactation while in multiparous cases number was progressively decreasing since the first month. Multiparous were statistically more liable to mastitis than primiparous. Mastitis did not show effect on yield production. Mastitis costs included treatment products and discarded milk. Individual daily production at each case onset was estimated by using monthly official milking records. An average mastitis case cost was 73.93 �, cheaper in primiparous than in multiparous because of lower milk production. Average discarded milk represented 74% of total cost per case. Mastitis costs were 117 � per infected cow and lactation. Then, annual economic losses due to mastitis were 3,190 � per average herd, showing the concern of producers on selecting resistant animals as well as the importance of the implementation of systematic recording for clinical mastitis in Spanish dairy farms.Se ha estudiado la mamitis clínica en 25 explotaciones utilizando 1.054 casos registrados desde abril de 2005 a diciembre de 2006. Los objetivos del trabajo fueron determinar la incidencia, analizar si la producción se vio afectada y calcular los costes generados en el año 2006. El 25% de las lactaciones presentaron algún episodio de mamitis, siendo la recurrencia media de 1,64. El 29% de los primeros casos se diagnosticaron en el primer mes tras el parto. Las primíparas fueron más susceptibles al principio y al final de la lactación, mientras que las multíparas presentaron menos casos según avanzaba la lactación. Sólo resultaron estadísticamente significativos el rebaño y el número de lactación, siendo las vacas con más de un parto más propensas a la mamitis. La producción de leche no se vio afectada. Los costes de mamitis incluyeron los correspondientes a medicamentos y a la leche retirada no comercializada. La producción individual diaria en el momento de la infección fue estimada utilizando el control lechero mensual oficial. El coste medio de mamitis fue de 73,93 �, siendo más caro en las multíparas debido a una mayor producción. El coste medio por media de leche retirada representó el 74% del coste por caso. El coste por vaca infectada fue de 117 � por lactación, lo que supone unas pérdidas económicas anuales por rebaño medio de 3.190 �, justificando la preocupación de los productores por seleccionar animales resistentes y la necesidad de sistematizar la recogida de mamitis clínicas en las explotaciones lechera españolas

A bio-economic model to improve profitability in a large national beef cattle population

A bio-economic model was developed for estimating economic values for use in improving profitability in a large national beef cattle population from birth to slaughter. Results were divided into fattening costs, production costs and income. Economic values were derived for 17 traits for two regions, mature weight (- 0.43 € and - 0.38 €/+1 kg of live weight), age at first calving (- 0.13 € and - 0.11 €/+1d), calving interval (-1.06 € and -1.02 €/+1d), age at last calving (0.03 € and 0.03 €/+1d), mortality 0-48 h (-5.86 € and -5.63 €/1% calves per cow and year), pre-weaning mortality (-5.96 € and -5.73 €/+1% calves per cow and year), fattening mortality (-8.23 € and -7.88 €/+1% calves per cow and year), adult mortality (-8.92 € and -7.34 €/+1% adult cows per cow and year), pre-weaning average daily gain (2.56 € and 2.84 €/+10g/d), fattening young animals average daily gain (2.65 € and 3.00 €/+10g/d), culled cow in fattening average daily gain (0.25 € and 0.16 €/+10g/d), culled cow dressing carcass percentage (3.09 € and 2.42 €/+1%), culled cow price (4.59 € and 3.59 €/+0.06 €/kg), carcass conformation score (16.39 € and 15.3 €/+1 SEUROP class), dressing carcass rate of calf (18.22 € and 18.23 €/+1%), carcass growth (9.00 € and 10.09 €/+10g of carcass weight/d) and age at slaughter (0.27 € and 0.44 €/+1d). Two sample herds were used to show the economic impact of calving interval and age at first calving shortening in the profit per slaughtered young animal, which was 178 € and 111 € for Herds A and B, respectively. The economic values of functional traits were reduced and production traits were enhanced when fertility traits were improved. The model could be applied in a Spanish national program

Structural equation models to disentangle the biological relationship between microbiota and complex traits: Methane production in dairy cattle as a case of study

The advent of metagenomics in animal breeding poses the challenge of statistically modelling the relationship between the microbiome, the host genetics and relevant complex traits. A set of structural equation models (SEMs) of a recursive type within a Markov chain Monte Carlo (MCMC) framework was proposed here to jointly analyse the host–metagenome–phenotype relationship. A non‐recursive bivariate model was set as benchmark to compare the recursive model. The relative abundance of rumen microbes (RA), methane concentration (CH4) and the host genetics was used as a case of study. Data were from 337 Holstein cows from 12 herds in the north and north‐west of Spain. Microbial composition from each cow was obtained from whole metagenome sequencing of ruminal content samples using a MinION device from Oxford Nanopore Technologies. Methane concentration was measured with Guardian® NG infrared gas monitor from Edinburgh Sensors during cow's visits to the milking automated system. A quarterly average from the methane eructation peaks for each cow was computed and used as phenotype for CH4. Heritability of CH4 was estimated at 0.12 ± 0.01 in both the recursive and bivariate models. Likewise, heritability estimates for the relative abundance of the taxa overlapped between models and ranged between 0.08 and 0.48. Genetic correlations between the microbial composition and CH4 ranged from −0.76 to 0.65 in the non‐recursive bivariate model and from −0.68 to 0.69 in the recursive model. Regardless of the statistical model used, positive genetic correlations with methane were estimated consistently for the seven genera pertaining to the Ciliophora phylum, as well as for those genera belonging to the Euryarchaeota (Methanobrevibacter sp.), Chytridiomycota (Neocallimastix sp.) and Fibrobacteres (Fibrobacter sp.) phyla. These results suggest that rumen's whole metagenome recursively regulates methane emissions in dairy cows and that both CH4 and the microbiota compositions are partially controlled by the host genotype.National plan of research, development and innovation 2013‐2020, Grant/ Award Number: RTA2015‐0022‐CO3 (METALGEN)UCR::Vicerrectoría de Docencia::Ciencias Agroalimentarias::Facultad de Ciencias Agroalimentarias::Escuela de ZootecniaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Centro de Investigación en Nutrición Animal (CINA