An investigation of 5186 hock maps, from 3691 cows with hair loss on the hocks from 76 UK dairy farms, identified six risk factors associated with area of hair loss: higher locomotion score; poor cleanliness; higher mean milk yield; low body condition score, prolonged winter housing and certain combinations of stall base and bedding materials. Another finding was significantly poor correlation between a categorical scale and the continuous measure of hair loss. Hair loss on the hocks of 70 heifers (three herds) was observed monthly from Sep 2008-Mar 2010. The results imply that lameness precedes hair loss on the hock and not vice versa, i.e. lame animals develop hair loss rather than hock hair loss leads to future lameness. Poor cleanliness score and higher milk yield were associated positively with the risk of having hair loss on the hock. Based on the total 6889 observations from 731 cows in four herds, cows with a greater decrease in BCS (compared to BCS at calving) had higher probability of becoming lame and lower probability of recovering. Also, increase in BCS from calving was associated with lower probability of cows moving from non-lame to lame state and higher probability from lame to non-lame. Days of lactation, months of calving and parity impacted upon both non-lame to lame and lame to non-lame transitions. Analysis of 678 cows from four herds found that cows with chronic lameness had a lower probability of conception and a longer calving to conception period compared with healthy cows. Further, cows with lower average BCS had a lower probability of conception and were more likely to be lame. However, these factors didn’t influence the likelihood of an individual AI leading to pregnancy.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:635116 |
| Date | January 2014 |
| Creators | Lim, Poh Ying |
| Publisher | University of Nottingham |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://eprints.nottingham.ac.uk/14534/ |
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