Effect of housing and feeding system factors on bovine welfare
- Autores: Lourdes Llonch
- Directores de la Tesis: Alfred Ferret i Quesada (dir. tes.), Lorena Castillejos (codir. tes.)
- Lectura: En la Universitat Autònoma de Barcelona ( España ) en 2021
- Idioma: inglés
- Tribunal Calificador de la Tesis: Maria Devant Guille (presid.), Aranzazu Villagra Garcia (secret.), Isabel Blanco Penedo (voc.)
- Programa de doctorado: Programa de Doctorado en Producción Animal por la Universidad Autónoma de Barcelona
- Materias:
- Enlaces
- Tesis en acceso abierto en: TDX
- Resumen
The farm management strategies in the cattle production system can improve animal welfare as well as other factors related to the production system. In this doctoral thesis, the strategies studied were a feeding system in beef cattle and a housing system in dairy cows, which modify farm resources or management to meet animal needs.
In the first study, the objective was to establish the optimal physical effective fiber (peNDF) proportion in high-concentrate diets fed to beef cattle, to reduce the risk of subacute ruminal acidosis. Simmental heifers in experimental conditions were fed 4 diets with different peNDF proportions: 6.4%, 10.4%, 13.6%, and 15.4%, offered ad libitum as total mixed ration, and containing 15% barley straw and 85% concentrate. Records about intake, intake by particle size, feed sorting, behavioral activities, and rumen pH provided insight on the proposed objective. The results suggested that the 10.4% diet best met the requirements of not compromising intake, limiting sorting behavior, and promoting time spent ruminating to reduce the number of hours under rumen pH thresholds. In addition, dietary peNDF has to be increased in cattle diets because it stimulates rumination activity, but it must be done at a level which does not reduce intake or lead to sorting against large particles.
In the second study, the objective was to compare forest biomass to sawdust as bedding material for compost-bedded pack (CBP) barns on CBP performance, bedding microbial counts, and welfare of nonlactating cows. Holstein cows in experimental conditions were allocated on a CBP with sawdust (CBP-S) or forest biomass (CBP-FB). The results of CBP temperature, moisture and C:N ratio showed that CBP performance was worse in CBP-FB than in CBP-S. In addition, cow comfort was worse in CBP-FB than in CBP-S considering the results obtained for time needed to lie down. However, bedding microbial counts showed that some microbial species were better controlled in CBP-FB than in CBP-S. Nevertheless, although forest biomass appeared to support a composting process and controlled the temporal evolution of bedding microbial counts of some species, higher required volumes of forest biomass and market prices of materials could have a greater economic impact on farm profitability.
In the third study, the objective was to ascertain the agronomic value of both materials resulting from the CBP. Once cows had been moved away, the CBP materials were used to build 2 composting piles with the further objective of ascertaining the agronomic characteristics of both materials after conducting an additional composting process. Some characteristics of chemical composition and granulometry of raw forest biomass made it a suitable bedding material to be used as CBP, but its high moisture content could limit the ability to absorb liquid manure. Taken together the degree of stability of the organic matter with the temperature evolution of CBP, this suggests that a real composting process did not occur in any material. The composting process of the piles did not lead to any relevant change in CBP materials, and only the organic matter of forest biomass pile was stabilized. From the agronomic point of view, sawdust and forest biomass presented potentially valuable characteristics as regards organic amendment in the soil, thanks to their high organic matter content and low nutrient content.
