Saturday 18 October 2014

Thin goat syndrome : Is new computer software the answer?

You can see the difference, Pia in the middle with prominent spin
Pia is thin, not quite a walking hat rack but she is about condition score 1.5 soon she'll be verging on emaciated. The other two, Acorn and Hebe are condition score 2.5, just right for this stage of lactation so why such a difference? Some goats, according to Mary with her 60+ years of goat keeping are, "just always thin".

Pia is a "British" Toggenburg as opposed to a Toggenburg and that could account for some of the difference like the difference between Holstein cows and Friesian cows thirty years ago. The Holstein is an extreme dairy type of animal while the Friesian then was more or less dual purpose, good for milk and good for beef.

Thin goat Pia on the left Acorn on the right
British Toggenburgs are bigger, rangier more wedge shaped, altogether more extreme dairy type than the Toggs because they've been selected for high milk production for generations. So that could account for part of the difference between them.

Pia reared twins to weaning at 12 weeks but then so did Acorn who is well padded but doesn't produce quite as much milk. Is Pia the extreme dairy goat "milking off her back"? In other words is she  mobilising fat to produce milk because she cannot consume enough energy and protein to sustain her yield because of her genetic make up?

This is week 29 of Pia's lactation so input and output of energy should be in balance. Tapeworm infestation is a possibility but didn't show up the last time her faecal samples were analysed.  Johne's Disease is a remote and unlikely possibility so what to do?

Balancing rations for ruminants isn't an exact science even though  50 years ago we did it with simultaneous equations, and then "Pearson's square" method. I was never keen on algebra! But this week I discovered the latest  ration formulation software for goats on an American university website, its usable on-line and its free. So I can check my more intuitive approach to rationing against this "expert system" and let you know the result in a week or two.

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