Feeding silage to fattening pigs – effects on nitrogen utilization and ammonia losses from fresh manure

ABSTRACT

This study evaluated the effect of feeding silage to pigs on nitrogen (N) utilization and ammonia (NH₃) volatilization. In total, 128 Yorkshire × Hampshire (30–110 kg) pigs were fed commercial feed (Control) or commercial feed mixed with dried, milled silage in pelleted form (Pellet-S), fresh, chopped silage (Silage-Ch) or intensively treated silage (Silage-Pr). Silage replaced 20% of the crude protein (g/kg). Diet affected daily N excretion, which was higher for pigs fed Silage-Ch and Silage-Pr than for pigs in the Pellet-S and Control treatments. Ammonium nitrogen (NH₄-N) content in the manure and NH₃ volatilization from fresh manure were higher for Control pigs than for pigs in the other treatments. Overall, these results show that pre-treatment of silage influences N utilization and excretion. Furthermore, the results indicate that feeding silage to pigs can reduce NH₃ volatilization from fresh manure.

KEYWORDS:

• Finishing pig
• silage
• TMR
• nitrogen
• ammonia volatilization

Acknowledgements

The authors would like to thank the staff at staff at Lövsta pig research unit, Swedish University of Agricultural Sciences, for the daily care of the pigs during the study; Marianne Tersmeden at RISE Research Institutes of Sweden, Uppsala, for help with preparation of samples and analysis of NH₃ volatilization; and the staff at Genevad Grönfodertork, which provided the pelleted silage, and at Swedish Agro (Kalmar, Sweden), which optimized and provided the diets used in this study.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

Raw data were generated at the Swedish University of Agricultural Sciences research station at Funbo Lövsta, Uppsala, and at RISE Research Institutes of Sweden, Uppsala. Derived data supporting the findings of this study are available from the corresponding author JF on request.

Additional information

Funding

This study was funded by the Swedish Research Council for Environment, Agricultural Science and Spatial Planning (Formas): [grant number 2018-02391].