- ItemOpen AccessAnálisis de los efectos ambientales y genéticos que afectan a la producción de leche en vacas nodrizas de la raza Parda de Montaña(Asociación Interprofesional para el Desarrollo Agrario, 2015) Cortés Lacruz, Xavier; Revilla, Ricardo; Casasús Pueyo, Isabel; Blanco Alibés, Mireia; Sanz Pascua, Albina; Villalba Mata, DanielThe objective of this study was to analyse the environmental and genetic effects in monthly milk production of Parda de Montaña beef cows. Five hundred and eight lactations from 246 cows were studied. Milk production was obtained by machine milking following oxytocin stimulation. Milk production in each month of lactation (1 to 5) was treated as a different trait. The model included the animal effect (random), level of nutrition of the cow, calving season, sex of calf, calf supplementation and calf management. The animal genetic effect accounts from 19 to 40% depending on the month of lactation, and the genetic correlation between months was higher than 53%. The magnitude of the environmental effects changes between months. Autumn calving cows produced more milk in the first month of lactation whereas spring calving cows produced more in the 4th and 5th month of lactation. The level of energy in the cow ration affected the milk production from the second to the fifth month of lactation. The sex, supplementation and management of calf did not have consistent effects on milk production. Nevertheless the calf related factors have punctual effects that recommend the inclusion of these effects in future models.
- ItemOpen AccessComponentes de la eficiencia alimentaria en cerdos Duroc y su relación genética con la calidad de la carne(Asociación Interprofesional para el Desarrollo Agrario, 2015) Sánchez, J. P.; Reixach, Josep; Quintanilla Aguado, Raquel; Estany Illa, Joan; Ibáñez-Escriche, N.; Rothschild, Max Frederick; Piles, M.This study reports estimates of the genetic correlations between feed efficiency (FE) components, ultimate pH (pH24), intramuscular content (IMF) and the selection criteria of the population: body weight (BW180) and back fat (BF180) at 180d. Average daily feed intake (FI), body weight (BW) and backfat thickness (BT) was weekly recorded from 15 to 26 weeks of age on 1076 pigs, and IMF and pH24 on 492 and 610 carcasses. FE components were defined from a random regression model for residual feed intake (RFI). The terms included were RFI per unit of metabolic weight (MBW), RFI per unit of ADG and an intercept, and for all these terms permanent and additive genetic effects were assumed. Individual variation in MBW is the only term having effect on RFI variation. High RFI intercept are associated with high content of intramuscular fat (0.41(0.10)) and low pH24 (-0.35(0.12)). The genetic correlation of RFI intercept with BF180 was 0.51(0.10), and that between RFI per unit of MBW and BW180 was -0.31(0.13); the genetic correlation between BF180 and BW180 was 0.63(0.01). These figures could make difficult the indirect improvement of FE through BF180 and BW180.
- ItemOpen AccessEstudio de la capacidad estabilizadora de una mezcla comercial de sustancias flavonoides (Bioflavex ®) sobre la fermentación ruminal en situaciones de acidosis inducida(Asociación Interprofesional para el Desarrollo Agrario, 2011) Balcells Terés, Joaquim; Arís, A.; Devant, M.; Crespo, J.; Seradj, Ahmad RezaThe effect of flavonoids Bioflavex ® (Exquim, SA, Barcelona Spain) on the prevention of rumen acidosis was studied in a 2 x 8 cross-over design using 8 crossbreed heifers (451.4 ± 14.32 kg of LW). Each period consisted of 22 d, from d1 to d20 animals were fed ryegrass hay , on d21 animals were fasted and d22 acidosis was induced by supplying 5 kg of ground wheat through the rumen cannula, the wheat was supplemented with (FL: 0.3‰) or without (CTR) flavonoids. PH decreases after wheat supplementation was lesser (P < 0.05) in FL than in CTR heifers (6.29±0.031 and 5.98± 0.029 for FL and CTR, respectively). Lactate concentration increased (P<0.005) with wheat supplementation being such increase numerically lesser (P < 0.09) in FL (from 36.8 to 106.6 mg/l) than CTR heifers (from 36.5 to 138.3 mg/l). After wheat supplementation, titers of Streptococcus bovis and Selenomonas. ruminantium increased whereas Megaesphera elsdenii increased only in FL heifers (P < 0.05). These results indicate that supplementation with Bioflavex® may be effective in reducing the incidence of rumen acidosis and it would be partially explained by flavonoids modulation of titers of lactate-consuming microorganisms such as M.elsdenii.
- ItemOpen AccessOptimización de los procesos de co-digestión anaerobia de purín de cerdo a partir de subproductos agrícolas como co-sustratos y heces de vacuno como co-inóculo(Asociación Interprofesional para el Desarrollo Agrario, 2011) Morazán Nuñez, Henris Jobany; Seradj, Ahmad Reza; Hermida, B.; Álvarez Rodríguez, Javier; Babot Gaspa, Daniel; Balcells Terés, JoaquimAnaerobic fermentation of the slurry allows for, i) Taking advantage of waste energy and ii) Reduce the emission of harmful (NH3) and greenhouse gases (e.g. CH4 and N2O). Generation of pig slurry, in those areas with a high concentration of pig farms (e.g. Catalonia and Aragon), became an environmental problem but also constitute abundant resource for energy-recycling. The slurry potential as a substrate for anaerobic fermentation is low, however this performance can be improved by synergic combination with other substrate as agro-industrial by-products. The objective of the present assay was to study the in vitro potential of some local by-products (i.e. wheat straw, apple pulp and sugar beet pulp) as a co-substrate and ruminant faeces as co-inoculum to optimize CH4 under anaerobic fermentation. The use of referred co-substrates improved significantly biogas and CH4 production although a negative relationship between methane production and slurry dilution was detected (4 and 6% vs. 2% slurry DM, P <0.05).
- ItemOpen AccessFactores de explotación que afectan a la composición de purín en cerdos de engorde(Asociación Interprofesional para el Desarrollo Agrario, 2011) Álvarez Rodríguez, Javier; Hermida, B.; Teira Esmatges, Maria Rosa; Boixadera Llobet, Jaume; Virgili Sanromà, Josep M.; Babot Gaspa, DanielThis study evaluated the effect of certain farming factors (period of year, feed to gain ratio and feed presentation system) on the slurry composition of growing-finishing pig farms (n=23). Feed to gain ration hardly affected chemical composition of slurry, whereas period of year only affected the organic matter content, which was lower in the hot than in the cold period. Likewise, feed presentation system showed a significant effect on some nutrient contents (organic matter, ammonium nitrogen and potassium), which were greater in wet/dry than in dry feeder type. These results highlight the importance of water and feed equipment on the excreta composition of fattening pigs.