Page 9 - Clinical Connections - Summer 2023

 

 

 

 

 

Page 9 - Clinical Connections - Summer 2023
P. 9

Pathology
        LAMB PREDATION: WHO DUNNIT?

        Henny Martineau, Head of Veterinary Forensic Pathology and Lecturer in Anatomic Pathology


                e have been collecting data from   but badgers may also play a role.
                sheep farmers on the predation of   Since the 1992 Protection of Badgers Act,
        W lambs by wild animals in the UK.   there has been an increase in the badger
        Predation is defined as “the act of a predator   population and, somewhat unsurprisingly,
        species catching, killing, and subsequently   an increase in claims that they kill lambs.
        eating  parts  of  their  prey.”  Predation  of   However, there are no recorded patterns
        lambs by wildlife not only causes detrimental   of predation by badgers in the literature.
        suffering to lambs and ewes but can also   Therefore, another aim of this study was to
        have a significant emotional and economic   find what criteria farmers use to decide if a
        impact on farmers.                  lamb has been killed by a fox or a badger.   A lamb with missing head and tail, which can
          The aim of the research is to improve the   One way of helping to identify the   indicate that it was scavenged by a fox
        current understanding of the incidence of   predator species is to perform a post
        lamb predation throughout the UK, identify   mortem examination on the dead lamb. At
        risk  factors  involved,  and  find  out  more   post mortem, the first thing to determine is
        about possible species contributing to these   whether the lamb was really predated or
        losses.                             actually scavenged after it died from another
          I  developed  a  particular  interest  in  this   cause. We do this by looking for evidence
        area after my involvement in an investigation   of  fresh  blood  associated  with  wound
        into the cause of a series of cat mutilations   edges, which would indicate the animal was
        across  England.  Originally  thought  to  be   bleeding and therefore alive at the time of
        caused by a human (aka ‘the Croydon Cat   the attack.
        Killer’), we used DNA analysis and detailed   If  there is no  blood,  then  we  assume
        post mortem examination protocols, to show   the body parts were removed after death   One  aim  of  the    study  is  to  find  what
        the injuries to be consistent with scavenging   (scavenged) and the lamb likely died   criteria farmers use when deciding if a lamb
                                                                                 has been killed by a fox or a badger
        by a fox after the cats had died. The causes   from another cause. Then we look for the
        of death were variable, but to our surprise   patterns of mutilation i.e. specific parts of the   in  the  skin  and  underlying  soft  tissues,
        some of them had been predated by foxes.   carcasses that are missing, which can differ   or marks from claws or teeth on fractured
                                            between predator species. For example,   bones.
        Foxes and badgers                   when  cats  are  scavenged  by  foxes,  the   By  combining  the  post  mortem  findings
        Previous  research  has  shown  that  more   most common missing body parts are the   of predated lambs with DNA analysis of a
        than half of farmers reported the loss of at   head, neck and tail, but when they are   swab from the mutilation site, which should
        least one lamb to fox predation in their most   scavenged by coyotes, removal of internal   have saliva from the predator species, we
        recent lambing season, while another study   organs is more common.     can get more accurate information on the
        indicated that predation by wildlife was the                            particular predator species involved in the
        main cause of lamb mortality.         Other evidence of the predator involved   lamb death. Availability of lamb carcasses
          In the UK, foxes are considered to be one   can be in the form of excrement on or near   for  PM  can  be  a  challenge  however,  as
        of the main wild predator species for lambs,   the carcass, puncture wounds from teeth   predators often remove the carcass or
                                                                                farmers do not have the time to save them
                                                                                during the busy lambing period.
                                                                                 Part of this research is being performed
                                                                                by  final  year  veterinary  student  Hasita
                                                                                Dodhia as part of her eight-week research
                                                                                project,  which  takes  the  form  of  a  short
                                                                                questionnaire.  We  currently  have  184
                                                                                responses, which goes to show what a
                                                                                relevant topic this is for farmers.









                                                                                       For the Diagnostic Pathology Service,
                                                                                     please call:01707 666 208
                                                                                       Email:
         Foxes are considered to be one of the main wild predator species for lambs in the UK  diagnosticlabs@rvc.ac.uk


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