Suitability of a lime source high in manganese as a feed ingredient for sheep

Abstract

An investigation was conducted to ascertain whether a source of feed lime (Ouplaas lime) high in manganese (5000 mg Mn/kg) is a safe feed ingredient for sheep. Two levels of Ouplaas lime, 1% and 4%, were included in a sheep finishing diet and compared with another lime source (Kulu lime; 45 mg Mn/kg) which was included at the same levels in the diets. Lambs were fed individually for 69 days. In the final feed mixtures none of the diets contained toxic levels of any minerals. No significant differences between treatments with the same level of lime inclusion occurred in: growth rate, feed intake and utilization, plasma enzyme levels, mineral concentrations in plasma, faeces and kidneys, mineral content of livers, haematology, histopathology of livers and kidneys and bone measurements. It is concluded that the Ouplaas lime, when included at realistic concentrationsin diets, poses no risk to the health of sheep.

Ondersoek is ingestel na die veiligheid om 'n voerkalk (Ouplaaskalk) met 'n hoë mangaaninhoud (5 000 mg Mn/kg) aan skape te voer. Die Ouplaaskalk is teen 1% en 4% in 'n vetmestingsrantsoen vir lammers geplaas en vergelyk met 'n ander b'ron van kalk (Kulukalk; 45 mg Mn/kg), ingesluit teen dieselfde vlakke. Lammers in die vier behandelings is vir 69 dae individueel gevoer en daarna geslag. Die finale rantsoene het geen minerale teen toksiese vlakke bevat nie. Geen statisties-betekenisvollve verskille tussen behandelings wat dieselfde peil kalk bevat het, is waargeneem in: groeitempo, voerinname, voeromsetting, ensiempeile in plasma, konsentrasie van minerale in die plasma mis en niere, mineraalinhoud van die lewer, haematologie, histopatologie van die lewers en niere en metings op ribmonsters nie. Dit blyk dat Ouplaaskalk, mits dit teen realistiese vlakke in rantsoene gevoeg word, geen gesondheidsrisiko vir skape inhou nie.

Keywords: Feed lime, health, manganese, sheep.