meaning of dreams farm

In my dream I'm working on a farm that I used to go to when I was younger, but I am the age I am now. The farmer tells me to train four horses to pull a carriage, I see the horses moving around outside the barn we are standing in front of - two are brown and two are black. The farmer tells me that he has an idea about how to get the horses to behave well. He asks me to hold open a gate so that he and another farm worker can get a young bullock (male adolescent cow) into the barn. The bullock is mostly black with small patches of white colouring. I am an observer and don't know what is about to happen. The other farm worker gets the bullock to lie down, sits on the animals' side and then cuts of its head with a chainsaw! I am shocked in my dream, I try to ask the farmer why he has done this but he doesn't stop to tell me. I watch the farmer pick up the head by the ears and take it outside to show to the four horses. The horses, understandably, react fearfully to this. I woke up feeling quite disturbed by the events in the dream, but managed to get back to sleep without too much trouble. In the morning I felt very positive, which surprised me considering the content of the dream.

I am a 31 year old female. I've recently started a new short term contract with an organisation that I have worked for previously. I have a partner who I have been with for a number of years.