Effect of calf stimulation on milk ejection in reindeer (Rangifer tarandus)

  • Hallvard Gjøstein Agricultural University of Norway, Dept. of Animal and Aquacultural Sciences, P.O. Box 5025, N-1432, Ås, Norway.
  • Øystein Holand Agricultural University of Norway, Dept. of Animal and Aquacultural Sciences, P.O. Box 5025, N-1432, Ås, Norway.
  • Tore Bolstad Agricultural University of Norway, Dept. of Animal and Aquacultural Sciences, P.O. Box 5025, N-1432, Ås, Norway.
  • Knut Hove Agricultural University of Norway, Dept. of Animal and Aquacultural Sciences, P.O. Box 5025, N-1432, Ås, Norway.
  • Robert B. Weladji Agricultural University of Norway, Dept. of Animal and Aquacultural Sciences, P.O. Box 5025, N-1432, Ås, Norway.
Keywords: lactation, let down mechanism, milking, oxytocin, suckling

Abstract

The objective of this study was to establish methods for stimulating the milk ejection in reindeer kept for milking purpose. Calves were used to stimulate milk does’ let down. In experiment 1, five does were allowed olfactory, acoustic and visual contact with their calves during milking, whereas four does were milked in isolation. The treatment of the groups was alternated every day during the eight days experiment. Olfactory, acoustic and visual contact with the calf did not influence the doe’s milk yield. The milk yield varied significantly between individual females within treatment (P < 0.01). In experiment 2, the calves were allowed to suckle their mother for a short period (two seconds) prior to milking being initiated. The same alternate design as in experiment 1 with groups consisting of three and two animals respectively was used, and the experiment lasted four days. The pre-suckling stimulation significantly increased the milk ejection measured as milk yield (P < 0.05), and the residual milk after the treatment was negectible. Moreover, the milk ejection varied between individual females within treatment (P < 0.05). We conclude that it is possible to achieve a complete milk removal by machine milking after the does have been pre-stimulated by suckling of calves. Olfactory, acoustic and visual contact with calves during milking failed to influence the milk ejection in this study. However, the results have to be interpreted with caution due to limited sample size.

Abstract in Norwegian / Sammendrag: Formålet med dette forsøket var å prøve ut ulike metoder for å stimulere nedgivninga av melk hos rein. Kalvene ble tatt i bruk for å stimulere nedgivninga. I forsøk 1 hadde simla lyd-, lukt og synskontakt med kalven mens melkingen pågikk. Vi benyttet et ”switch back design” der fem simler hadde kontakt med kalven under melkingen og fire ble melket uten kontakt. Behandlingen ble byttet om annenhver dag i de åtte dagene forsøket varte. Lyd-, lukt og synskontakt med kalven under melking hadde ingen innvirkning på melkemengden ved maskinmelking. Det var imidlertid individuell variasjon i hvor mye melk man oppnådde hos simlene (P < 0.01). I forsøk 2 lot vi kalvene suge simlene en kort stund før simlene ble melket. Kalven ble sluppet inn til simla og sugingen ble avbrutt etter to sekunder. Deretter ble simla ført inn for maskinmelking. Forsøket varte i fire dager og vi benyttet samme ”switch back design” som i forsøk 1, med grupper bestående av henholdsvis to og tre dyr. Stimuleringa med suging hadde en signifikant innvirkning på nedgivninga. (P < 0.05), og mengden gjenværende melk var minimal. Dessuten var det en signifikant individuell variasjon i melkemengden innen behandlingen (P < 0.05). Vi konkluderer med at det er mulig å oppnå en fullstendig tømming av juret ved maskinmelking dersom simlene først er blitt stimulert med suging av kalven. Lyd-, lukt- og synskontakt med kalven under melking hadde ingen innvirkning på nedgivninga av melk i dette forsøket. Resultatene må imidlertid tolkes med varsomhet siden det statistiske utvalget er begrenset.

Published
2004-04-01
How to Cite
GjøsteinH., Holand Øystein, BolstadT., HoveK., & WeladjiR. B. (2004). Effect of calf stimulation on milk ejection in reindeer (Rangifer tarandus). Rangifer, 24(1), 3-6. https://doi.org/10.7557/2.24.1.261
Section
Articles