An experimenl was carried out over 2 ye;irs on gras,s and grnss/ctover swards in SW Engl;ind lo compare herbage yields and N recovery following .surface application or shallow injection of cattle slurry id three different times of application. In the .second year, losses of N via ammonia volaiilization, denilrification and nitrate leaching were niea,surcd from applications to the grass sward. On the grass sward, there was no significant effect of time or method of application on dry-matter (DM) yield in the first year, although shallow injection reduced apparent N recovery (ANR) in the herbage by 43% when compared with stirface application. In the second year, shallow injection reduced DM yields by 26% and ANR by 48%, On the grass/clover sward, there were no significant effects of time or method of application on DM yieids or ANR in either year. Inclusion of dicyandiamicle (DCD) in the October slurry applications had no significant effect in the first year, but in the second year on the grass sward increased DM yield by 31% and 14% and ANR by 156% and 42% for .shallow injection and surface applications respectively. Measurements in the second year on the grass sward showed a reduction in N loss by ammonia volatilization using shallow injection of 40% and 79% for March and June applications respectively. Losses due to denitrification were greatest following October application. Shallow injection increa.sed denitrification losses foltowing March application, but there were no significant differences following October or June Correspondence: T.H. MJsselbrook, Institute of Grassland and Environmental Research, Norlh Wyke, Okehampion, Devon EX20 2SB,UK.applications. N losses due to leaching were small, with no significant difference between treatments. Reasons for the reductions in DM yield and ANR following shallow injection, despite the large reduction in N loss by ammonia volatilization, are discussed.

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Neonatal mortality is greater