Day 091 - 17 Feb 95 - Page 16

     
     1   Q.   What about crooked toes?
     2        A.  Well, crooked toes and spondylolisthesis, which is
     3        kinky back, the second one, they are both genetically
     4        determined conditions.  It is one that the breeders have
     5        been making good progress on on eliminating.  It is quite
     6        rare now to see both of those conditions.
     7
     8   Q.   The crooked toes can cause lameness in some circumstances?
     9        A.  Yes, it can.
    10
    11   Q.   When did it become rare to see those conditions?
    12        A.  There has just been a gradual reduction in the
    13        incidence of crooked toes over the years.  It is something
    14        that we do not tend to see nowadays compared with, say, 15
    15        years ago when it was quite common.
    16
    17   Q.   What would have been the position five to 10 years ago?
    18        A.  Much the same as today.
    19
    20   Q.   What percentage would that be affecting?
         A.  I cannot answer the question, I am sorry.  It is very,
    22        very low.
    23
    24   Q.   The spondylolisthesis, it says there: "Up to 20 per cent of
    25        a flock can show a degree of deformity without clinical
    26        signs.".  Is that the kind of level that you would have
    27        experienced at Sun Valley Poultry?
    28        A.  No.  This condition is very rare now.  I can go back to
    29        an incidence when I was first at Sun Valley where we tried
    30        a different breed and we had a very much higher incidence
    31        of this condition, so it indicated to me that the genetics
    32        was very important in determining the incidence of it.  Now
    33        we very rarely see it.
    34
    35   Q.   How often is "very rare"?
    36        A.  The occurrence may be just one or two birds in a flock
    37        on a routine postmortem sample.
    38
    39   Q.   So for each unit, for each shed, there would be one or two
    40        birds suffering from that?
         A.  There may be.  It is certainly very, very low.
    42
    43   Q.   That was from a routine sample, routine postmortem sample?
    44        A.  Yes, the clinical signs kinky back are very characteric
    45        and you know by observation in the flock whether there are
    46        likely to be birds suffering from this condition.  So,
    47        having been led by the clinical signs, you would then use
    48        the appropriate postmortem technique to examine a back
    49        bone.
    50 
    51   Q.   But it says:  "Up to 20 per cent of a flock can show a 
    52        degree of deformity without clinical signs"? 
    53        A.  That may be so, but I do not know how you would decide
    54        that.
    55
    56   Q.   When you do a routine postmortem sample, how many birds are
    57        involved in that?
    58        A.  The normal, from any one unit, if you ask for a
    59        postmortem sample, is to examine between six and ten birds.
    60