Recurrent  Urethral  Obstruction  Secondary  to  Urolithiasis  in  a  Nigerian  Dwarf
Goat
Vanessa  Bradley,  Michigan  State  University  CVM  2014
Case  Summary
This  case  report  describes  a  4  year  old,  male  castrated  Nigerian  Dwarf  goat   diagnosed  recurrent  obstructive  urolithiasis  at  20  months  of  age  that  was  managed   both  conservatively  and  surgically  over  the  course  of  two  years  with  repeated   urethral  catheterization  and  three  perineal  urethrostomy  operations.
Introduction
Urolithiasis  describes  the  formation  of  urinary  calculi,  and  refers  to  the   disease  conditions  that  occur  as  a  result,  such  as  urethral  obstruction.
1    Urolithiasis   affects  many  domestic  species,  including  companion  and  food  animals.    Urolithiasis   is  commonly  reported  in  young,  castrated  male  pet  goats.
2    Some  factors  associated   with  the  development  of  urinary  calculi  in  goats  include  gender,  age  at  castration,   and  diet,  as  well  as  urine  pH  and  concentration.
2
Urolithiasis  is  significantly  more  common  in  male  goats  compared  to  female   goats,  simply  due  to  the  anatomy  of  the  male  urethra.    In  contrast  to  the  relatively   short,  wide,  and  straight  urethra  present  in  females,  the  male  urethra  is  long,   narrow,  torturous,  and  prone  to  obstructions,  particularly  in  the  sigmoid  flexure  and   urethral  process.
2-­‐4    The  age  at  which  castration  occurs  also  is  an  important  factor  in   the  development  of  urolithiasis.    Early  castration  results  in  penile  hypoplasia,   leading  to  a  decrease  in  the  bore  size  of  the  urethra,  as  well  as  failure  of  the  urethral   process  to  mature  and  completely  separate  from  its  distal  attachment  to  the   preputial  mucosa.
2,3    The  decreased  bore  size  of  the  urethra  is  a  major  predisposing   factor  for  obstructive  urolithiasis.
In  addition  to  anatomical  factors,  there  is  considerable  research   demonstrating  that  dietary  factors  also  contribute  to  the  development  of  caprine   urolithiasis.    Pet  goats  are  commonly  fed  diets  that  exceed  their  caloric   requirements,  and  popular  diets  often  contain  alfalfa  hay,  which  is  high  in  calcium,   and  grains  that  tend  to  be  high  in  phosphorus.
9    These  diets  contain  excess  minerals,
1

such  as  calcium  and  phosphorus  that  encourage  urolith  formation.
2,5    Several   investigators  have  created  a  nutritional  model  for  urolithiasis  in  various  species,   and  one  of  these  studies  demonstrated  a  higher  incidence  of  urolithiasis  in  goats  fed   a  diet  with  increased  phosphorus  content  compared  to  those  fed  a  diet  with  a  lower   phosphorus  content 5 .    Struvite  (magnesium  ammonium  phosphate)  and  apatite
(calcium  phosphate)  uroliths  are  most  common  in  goats  fed  high  grain  diets,  which
makes  sense  as  calcium  and  phosphorus  are  often  fed  in  excess.
6
In  addition  to  gender,  age  at  castration,  and  diet,  urinary  pH  and   concentration  also  play  a  significant  role  in  the  formation  of  uroliths  and  subsequent   development  of  obstructive  urolithiasis.    Urinary  pH  is  a  major  factor  in  urolith   formation  –  both  struvite  and  apatite  uroliths  precipitate  in  alkaline  urine.
6,10,16
Stuvite  crystals  will  form  at  pH  7.2  to  8.4,  and  apatite  crystals  will  form  at  relatively   more  acidic  pH  range  from  6.5  to  7.5  compared  to  struvite  crystals.
7    Urine   concentration  is  another  important  factor  in  the  development  of  urolithiasis,  as   increased  urine  concentration  results  in  increased  precipitation  of  urinary   crystals.
2,6    Urinary  concentration  can  be  increased  due  to  decreased  water  intake,   or  increased  loss  of  water  from  the  body.    During  colder  months,  animals  tend  to   drink  less  water  and  thus  their  urine  is  more  concentrated,  increasing  the  likelihood   of  urolithiasis.    During  disease  states  of  increased  water  loss,  risk  of  urolithiasis  is   also  increased  as  urine  becomes  more  concentrated  due  to  increased  loss  or   decreased  water  intake.  The  body  naturally  produces  urinary  crystal  inhibitors  in   the  form  of  colloids  that  prevent  precipitation  of  crystals, 2,14  and  loss  of  these   colloids  can  result  in  precipitation  and  urolithiasis.    In  addition  to  urinary  crystal   precipitation,  desquamated  epithelial  cells  can  form  an  excellent  nidus  for  urinary   calculi  formation.
2    Desquamated  epithelial  cells  are  associated  with  vitamin  A   deficiency  and  infections  within  the  bladder.
2,6,8
Diagnosis  of  urolithiasis  in  goats  is  frequently  made  using  signalment,   history,  and  clinical  signs  alone,  though  other  modalities  such  as  ultrasound,   contrast  studies,  and  serum  biochemistry  can  provide  additional  information  that   can  be  particularly  valuable  to  assess  the  severity  of  the  condition  and  serve  as   prognostic  indicators.
2,10
2

Signalment  is  one  key  that  can  add  obstructive  urolithiasis  to  a  list  of   differential  diagnoses.    As  mentioned  previously,  castrated  males  are  more   commonly  affected  by  urolithiasis  than  intact  males.    A  retrospective  study  of  38   cases  of  caprine  urolithiasis  had  an  age  range  of  2  months  to  12  years  of  age.
27     Many   of  these  animals  were  obese  and  essentially  all  of  them  received  high  grain  diets.
The  same  study  also  found  an  increased  incidence  of  obstructive  urolithiasis  in  the   summer  and  winter.    This  may  be  related  to  the  water  balance  of  the  goats  –  during   the  winter,  urine  may  be  more  concentrated  due  to  decreased  water  intake.
Conversely  during  the  summer,  urine  may  be  more  concentrated  due  to  increased   water  loss  in  the  heat.    A  different  retrospective  study  concluded  that  pygmy  goats   were  overrepresented  in  the  study  population  compared  to  other  breeds.
10    The   higher  incidence  of  obstructive  urolithiasis  in  pygmy  goats  may  be  due  to  the  fact   that  they  are  more  likely  to  be  kept  as  pets  and  thus  fed  inappropriate,  high  grain   diets  as  opposed  to  any  genetic  factor  linked  to  that  breed.    As  pets,  pygmy  goats  are   also  more  likely  to  be  castrated  earlier,  and  when  urolithiasis  occurs  are  more  likely   to  be  treated  due  to  the  emotional  attachment  by  the  owners.
10    A  different  study   reviewing  107  cases  of  urolithiasis  in  goats  found  urolithiasis  to  be  more  common  in   castrated  males,  and  African  dwarf  breeds.
21
History  and  clinical  signs  of  urolithiasis  vary  depending  on  the  degree  and   location  of  obstruction,  as  well  as  the  duration  of  obstruction.
6      In  cases  of   intermittent  obstruction,  owners  may  report  a  history  of  clinical  signs  that  wax  and   wane,  depending  on  degree  of  obstruction.    Early  signs  clinical  signs  of  obstruction   can  be  relatively  nonspecific  and  include  anorexia  and  lethargy.
2,6    As  the  disease   progresses,  clinical  signs  become  more  severe  and  apparent.    More  advanced  signs   commonly  include  stranguria,  hematuria,  vocalization,  tail  switching,  abdominal   distention,  restless  or  anxious  behavior,  to  depression  and  even  recumbency  in  the   advanced  stages  of  obstructive  urolithiasis,  especially  when  urethral  or  urinary   bladder  rupture  occurs.
2,6,10,13    Incomplete  obstruction  of  the  urethra  can  result  in   complete  obstruction  due  to  the  inflammation  caused  to  the  urethral  mucosa  by  the   urolith 6 .    Also  when  stranguria  is  present,  cystitis  and  ulcerative  posthitis  must  be   ruled  out,  as  the  clinical  signs  for  those  disease  processes  are  similar.
2    In  some
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cases  of  bladder  rupture,  an  initial  improvement  in  clinical  signs  may  be  noted   followed  by  a  marked  decrease  in  status  as  uremia  ensues.
2    When  goats  are   severely  depressed  following  rupture,  hepatoencephalopathy  and  enterotoxemia   must  be  ruled  out,  and  confirmation  of  urine  in  the  abdomen  can  diagnose  urinary   bladder  or  urethral  rupture.
2        The  progression  of  clinical  signs  vary,  but  one   retrospective  study  reported  the  median  duration  of  clinical  signs  prior  to   admission  to  be  30  hours.
10    If  obstruction  is  not  treated,  urinary  bladder  or  urethral   rupture  can  occur  in  24  –  48  hours.
2  The  entire  clinical  course  of  obstructive   urolithiasis  can  last  2  –  5  days  from  onset  to  death  if  appropriate  medical  or  surgical   intervention  does  not  occur.
2
The  physical  exam  is  often  a  key  component  of  the  diagnosis  of  urolithiasis  in   goats.    In  addition  to  vital  signs,  thorough  evaluation  of  the  prepuce  and  palpation  of   the  urethra  are  key  in  the  diagnosis  of  obstructive  urolithiasis.
2,6    The  physical  exam   can  easily  reveal  obstructions  of  the  urethral  process  and  distal  urethra  through   extrusion  of  the  penis.
6    A  supportive  sign  of  urolithiasis  is  the  presence  of  crystals   on  the  preputial  hair,  and  signs  of  sensitivity  or  pain  on  urethral  palapation.
6      In   cases  of  urinary  bladder  rupture,  bilateral  ventral  abdominal  distention  may  be   noted,  and  abdominocentesis  can  confirm  the  presence  of  urine  in  the  abdomen.
6    If   the  urea  nitrogen  or  creatinine  concentrations  in  the  peritoneal  fluid  is  equal  to  or   greater  than  those  concentrations  in  the  blood,  then  the  fluid  is  urine.
2    Urethral   rupture  can  also  result  in  subcutaneous  edema  near  the  prepuce.
6
Clinical  pathology  findings  will  vary  depending  on  the  duration  of  the  urinary   obstruction.    Common  abnormalities  include  azotemia,  hyponatremia,   hypochloremia,  and  hypokalemia.
6    More  severe  derangements  are  seen  in  cases  of   rupture  or  obstruction  of  longer  duration.
6    A  retrospective  study  of  107  cases  of   goats  with  uroliths  found  that  they  were  frequently  hypophosphatemic  at   admission,  and  hypochloridemic  metabolic  alkalosis  was  the  most  common  acid-­‐ base  abnormality.
21    In  cases  with  urinary  bladder  or  urethral  rupture,   hyponatremia  and  hyperkalemia  were  more  common.
21
Additional  diagnostic  modalities  include  contrast  radiography,   ultrasonography,  and  endoscopy.    Contrast  studies  can  aid  in  determining  the
4

location  of  an  obstruction  within  the  urethra,  and  rule  out  bladder  rupture.
2,20
Urethral  calculi  are  not  always  detected  on  survery  radiographs, 14  limiting  its  use  as   a  key  diagnostic  tool.    Ultrasonography  is  a  rapid,  minimally  invasive  method  to   determine  the  extent  calculi,  and  also  detect  free  abdominal  fluid  that  may  be   indicative  of  urinary  bladder  rupture,  which  can  be  important  in  the  decision  of  the   appropriate  treatment  strategy.
2,10    Urethral  endoscopy  can  also  be  used  to  both   evaluate  urethral  patency,  and  provide  information  regarding  long-­‐term  prognosis   by  evaluating  the  urethral  mucosa  following  relief  of  the  obstruction.
14    Normograde   cystourethrography  has  also  been  used  to  monitor  urethral  patency  following  tube   cystotomy  by  inserting  the  contrast  medium  through  the  tube  into  the  bladder  in   pigs  and  small  ruminants.
20    Survey  radiographs  and  excretory  urography  both  have   limited  use  in  the  diagnosis  and  management  of  urethral  urolithiasis  in  pigs  and   small  ruminants.
20
Arriving  at  a  diagnosis  of  obstructive  urolithiasis  is  relatively  easy,  however   selecting  the  best  treatment  modality  can  be  much  more  difficult.    Treatment   options  for  urolithiasis  include  medical  and  surgical  management.    In  general  less   severe  cases  with  incomplete  obstruction  are  more  likely  to  be  managed   successfully  medically,  compared  to  cases  of  more  severe  obstruction,  which  often   require  more  aggressive  surgical  treatment.
2,6    Numerous  studies  have  found  that   medical  treatment  in  combination  with  urethral  process  amputation  is  not  effective   long  term,  and  only  provides  temporary  relief  as  reobstruction  is  likely.
2,6,10,13
When  choosing  a  treatment  modality,  the  patient’s  intended  use  should  be   taken  into  consideration.    For  example,  the  surgical  treatment  for  breeding  goats   that  best  suits  continued  productivity  is  location  and  removal  of  the  urolith.
2      It  has   been  suggested  that  if  an  animal  is  to  be  used  for  breeding,  then  surgical  tube   cystotomy  is  the  best  choice,  but  if  the  animal  is  a  pet  and  urethral  patency  is  not   required,  bladder  marsupialization  is  the  better  option.
10    All  treatment  modalities   have  benefits  and  complications  associated  with  them,  so  selection  is  based  on  long-­‐ term  goals  for  the  individual  patient  and  the  owner’s  ability  and  willingness  to   finance  and  provide  aftercare  for  the  treatment.
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The  location  of  the  obstruction  is  also  taken  into  consideration  when   selecting  the  treatment.    For  example,  if  the  obstruction  is  present  in  the  urethral   process,  amputation  of  that  process  may  be  therapeutic  so  long  as  other   obstructions  are  not  present.
2    If  the  obstruction  is  proximal  to  the  urethral  process,   passing  a  urinary  catheter  for  retropulsion  may  alleviate  the  obstruction, 2  but  other   surgical  treatment  options  may  be  more  effective  to  prevent  reobstruction.
Regardless  of  the  treatment  modality  selected,  the  most  important   component  is  the  correction  of  fluid  and  electrolyte  abnormalities.
2,6    Correction   requires  intravenous  fluid  administration,  which  carries  the  risk  of  increased   bladder  distention  and  rupture  –  however  this  is  preferred  to  taking  an  unstable   animal  to  surgery.
10,12,13,19    During  fluid  resuscitation,  a  percutaneous  catheter  can   be  placed  into  the  bladder  lumen  to  prevent  bladder  rupture  while  stabilizing  the   animal  before  surgery.
14    This  is  the  desirable  alternative  to  repetitive  cystocentesis,   as  that  increases  the  risk  of  peritonitis  and  vesicular-­‐intestinal  adhesions.
15
Medical  treatment  options  for  obstructive  urolithiasis  include  dietary   modification,  addition  of  urine-­‐acidifying  agents  to  the  diet,  Walpoles  solution,  and   retropulsion.    Retropulsion  in  ruminants  is  not  as  successful  as  it  is  in  other   domestic  species  due  to  the  presence  of  the  urethral  diverticulum.
10,11    The  urethral   diverticulum  also  makes  it  difficult  to  pass  urinary  catheters  into  the  bladder,  and   also  difficult  to  retropulse  urethral  calculi.    If  retropulsion  is  attempted,   tranquilizers  and  antispasmodics  should  be  used  for  the  comfort  of  the  goat,  and  to   encourage  a  successful  outcome  of  the  procedure.
2    Therefore  dietary  modification   and  addition  of  urine-­‐acidifying  agents,  such  as  ammonium  chloride,  and  to  the  diet   are  more  commonly  used  for  the  conservative  treatment  of  obstructive  urolithiasis   in  goats.
Dietary  modification  and  addition  of  urine  acidifying  agents  such  as   ammonium  chloride  to  the  goat’s  diet  have  been  shown  to  be  effective  in  the   prevention  of  recurrent  obstructions,  and  are  an  important  component  of  both   medial  and  surgical  treatment.
2,4,6,16    A  high  roughage  diet  composed  of  alfalfa  and   mixed  grass  hay  without  grain  is  a  popular  dietary  recommendation  for  goats
6

affected  by  urolithiasis.
2,6    Adding  ammonium  chloride  will  decrease  urine  pH,  and   can  prevent  the  formation  of  struvite  and  apatite  crystal  formation.
16
Walpole’s  solution  is  composed  of  sodium  acetate  (1.16%),  glacial  acetic  acid
(1.09%),  and  distilled  water  (97.75%)  and  has  a  pH  of  4.52.
5    This  solution  has  been   used  to  dissolve  struvite  calculi  in  numerous  species,  and  was  investigated  for  use  as   a  treatment  for  urolithiasis  in  male  goats  in  retrospective  case  study  series.
25    In  this   study,  Walpole’s  solution  was  injected  into  the  bladder  using  ultrasound  guided   percutaneous  infusion  of  50ml  –  250ml  of  solution  to  reach  target  urine  pH  of  4  to  5.
To  reach  the  target  pH,  the  solution  was  administered  once  in  72%  of  goats,  twice  in
24%  of  goats,  and  three  times  in  4%  of  the  goats.    Of  the  25  male  goats  in  the  study,   urethral  obstruction  was  resolved  in  80%  of  the  goats,  and  the  remaining  20%  were   euthanized  due  to  unresolved  urethral  obstruction  and  the  owners  declining   surgery.    However,  30%  of  the  goats  that  were  discharged  returned  at  a  later  date   due  to  the  recurrence  of  urethral  obstruction.    In  addition  to  administration  of
Walpole’s  solution,  the  urethral  processes  were  amputated  if  still  intact,  and   ammonium  chloride  was  administered  in  84%  of  the  cases.    The  hospitalization  time   for  these  goats  ranged  from  0.5  to  8  days.    The  most  common  complication  noted   with  this  procedure  was  leakage  of  urine  from  the  puncture  sites  in  the  urinary   bladder.    Walpole’s  solution  is  known  to  be  irritating  to  mucous  membranes,  and   goats  that  were  euthanized  and  underwent  necropsy  had  signs  of  cystitis,  but  it  is   unclear  whether  Walpole’s  solution  caused  the  cystitis  or  if  it  was  pre-­‐existing.
25
Surgical  treatments  are  next  in  line  when  conservative  treatment  fails.    As   previously  mentioned,  it  is  imperative  to  stabilize  patients  prior  to  surgery  by   correcting  fluid  and  electrolyte  imbalances.
2    Traditional  surgical  treatment  options   include  urethral  process  amputation,  percutaneous  or  surgical  tube  cystotomy,   perineal  urethrostomy(PU),  and  bladder  marsupialization.    Recently,  laser   lithotripsy  has  been  safely  and  effectively  used  in  three  goats  to  treat  calculi  lodged   in  the  urethra.
14
Though  urethral  process  amputation  is  technically  a  surgical  procedure,  it  is   commonly  considered  part  of  medical  or  conservative  management  of  obstructive   urolithiasis  as  it  is  a  relatively  quick  and  simple  procedure,  and  is  often  one  of  the
7

first  treatments  performed.    However,  the  relief  provided  is  only  temporary,  and  80-­‐
90%  of  cases  will  reobstruct  within  hours  to  days.
13
Percutaneous  tube  cystotomy  can  be  used  to  avoid  general  anesthesia  in  high   risk  patients,  but  has  a  higher  complication  rate  compared  to  surgical  tube   cystotomy  and  bladder  marsupialization.
10,12    One  retrospective  study  found  that
50%  of  patients  had  catheter  displacement  that  required  a  second  procedure,   compared  to  12%  of  surgical  tube  cystotomy  patients.
10    The  marked  difference  is   likely  present  because  during  the  surgical  tube  cystotomy  procedure,  the  catheter   was  secured  in  the  bladder  with  a  suture,  which  was  not  possible  using  the   percutaneous  method.
10    Another  common  complication  found  was  adhesions  with   percutaneous  and  surgical  tube  cystotomy  between  the  small  intestines  and  bladder   in  the  goats  that  required  a  second  surgical  procedure  following  percutaneous  tube   cystotomy.
10,12
Surgical  tube  cystotomy  is  one  of  the  procedures  used  for  long-­‐term   treatment  of  obstructive  urolithiasis  in  goats,  and  may  be  the  best  surgical  option   for  breeding  animals  and  pets  for  long-­‐term  success.
10,12    Ewoldt  et  al 10  performed  a   retrospective  clinical  study  evaluating  the  short  and  long  term  outcome  of  tube   cystotomy  without  urethral  flushing  in  small  ruminants.    The  operation  was   completed  under  general  anesthesia  through  a  paramedian  incision  lateral  to  the   prepuce  halfway  between  the  scrotal  base  and  preputial  orifice.    The  urinary   bladder  was  located  and  isolated,  and  a  cystotomy  was  performed  near  the  apex  of   the  bladder  to  evacuate  urine  and  debris.    A  Foley  catheter  (size  dependent  upon   animal,  usually  18-­‐20  French)  was  inserted  through  a  stab  incision  4  -­‐10  cm   paramedian  from  the  celiotomy  incision,  and  then  was  secured  in  the  ventrolateral   aspect  of  the  bladder  on  the  same  side  as  the  celiotomy  incision,  and  was  secured   using  a  purse  string  suture.    The  catheter  was  used  to  pull  the  bladder  close  to  the   body  wall,  was  secured  to  the  skin  using  a  Chinese  finger  trap  suture.    The  external   end  of  the  Foley  catheter  was  left  uncovered.    Potential  complications  of  leaving   catheter  in  place  are  catheter  obstruction  and  accidental  removal,  neither  of  which   were  a  problem  in  the  present  study,  but  have  been  reported  in  previous  studies.
12
Urethral  patency  was  determined  after  7  days  of  free  drainage  by  intermittently
8

occluding  the  Foley  catheter  with  a  clamp.    If  animals  showed  signs  of  discomfort,   the  clamp  was  removed.    Once  the  animals  remained  comfortable  with  the  clamp  in   place  for  24-­‐48  hours,  the  Foley  catheter  was  removed.    The  mean  time  to  normal   urination  following  the  procedure  was  11  +  8  days,  which  may  have  been  affected  by   the  tubes  not  being  clamped  until  seven  days  after  the  procedure,  as  normal   urination  is  difficult  to  produce  before  the  tube  is  clamped.  This  study  reported  76%   of  all  animals  were  successfully  treated  by  the  time  of  hospital  discharge.    Of  the   animals  discharged,  90%  were  successfully  treated  by  tube  cystotomy.    At  six   months  follow  up  post-­‐surgery,  46%  did  not  have  any  recurrence  of  clinical  signs,   and  70%  were  still  alive.    Complications  of  tube  cystotomy  include  failure  to  relieve   obstruction,  peritonitis,  adhesions,  urethral  rupture,  and  catheter  dislodging  or   clogging  with  debris  from  the  environment  or  from  the  bladder  itself  (blood,  calculi,
“sludge”).
10,15    Plugged  catheters  could  often  be  managed  by  gentle  retrograde   flushing 10 ,  but  other  complications  required  additional  surgery.    One  study   conducted  by  Fortier  et  al 10  found  52%  of  goats  necessitated  a  second  surgery  due   to  complications  of  tube  cystotomy.    One  drawback  to  this  procedure  is  the  amount   of  hospitalization  required  afterwards,  which  may  be  limiting  due  to  owner’s   finances.
20
A  retrospective  study  on  the  outcome  following  tube  cystotomy  in  small   ruminants  reported  a  lower  rate  of  reobstruction  than  previous  studies,  and   attributed  that  in  part  to  dietary  changes  recommended  at  the  time  of  discharge.
The  researchers  recommended  the  drastic  reduction  or  elimination  of  grain  in  the   diets,  increased  grazing,  and  grass  hay  as  opposed  to  alfalfa  hay.    Feeding   ammonium  chloride  was  also  recommended.
10
In  pets,  a  perineal  urethrostomy  (PU)  is  a  salvage  procedure, 2  as  breeding   ability  is  lost  in  intact  males.      There  are  some  slight  variations  in  this  procedure,   and  it  will  be  described  as  performed  by  Haven  et  al  (1992).    This  procedure  is   performed  under  general  anesthesia.    A  midline  incision  is  made  over  the  penis  just   ventral  to  the  ischiatic  arch.    A  short  segment  of  penis  is  bluntly  dissected  to  free  it   from  surrounding  tissues  so  that  an  incision  can  be  made  into  the  urethra  through   the  urethral  muscle  and  corpus  spongiosum.    The  urethra  is  then  transected  distally,
9

and  that  end  is  sutured  to  the  subcutaneous  tissue  and  skin  of  the  initial  incision.
This  provides  a  larger  urethral  opening  that  will  allow  large  calculi  to  pass  without   causing  and  obstruction.    Disadvantages  of  PU  for  treatment  of  obstructive   urolithiasis  include  loss  of  breeding  ability  in  intact  males  and  poor  long-­‐term   results 13 .    Often  pet  goats  are  castrated,  so  loss  of  breeding  ability  is  not  an  issue.    In   cases  of  urethral  rupture,  primary  closure  of  the  urethra  is  rarely  an  option  and   second  intention  healing  is  usually  the  sole  option.
15    During  this  time,  urine  must  be   diverted  from  the  urethra  via  tube  cystotomy  or  bladder  marsupialization.
15
Perineal  urethrotomy  (PU)  and  urethrostomy  are  associated  with  poor  long   term  outcomes  due  to  stricture  formation,  resulting  in  recurrent  obstruction.
10,13
One  retrospective  study  examined  the  efficacy  of  PU  versus  cystotomy  with   normograde  and  retrograde  flushing,  and  concluded  that  cystotomy  in  combination   with  appropriate  dietary  management  following  surgery  produced  better  long  term   results  compared  to  PU  alone.
13    The  authors  did  believe  a  PU  may  be  indicated   when  urethral  rupture  was  eminent,  or  the  obstruction  could  not  be  relieved  by   flushing  attempts.
13
As  stricture  formation  is  a  common  complication  in  PU  operations,  prepubic   urethrostomy  is  a  secondary  operation  that  can  be  used  to  relieve  urinary  outflow   obstruction  from  the  stricture  formation.
24    However,  this  surgical  procedure  can  be   quite  involved  –  one  case  study  described  the  procedure  in  a  sheep  that  required   pubic  osteotomy  to  achieve  appropriate  urethral  exposure,  but  this  was  not   required  in  a  goat  with  the  procedure.
24    Essentially,  the  urethra  is  diverted  from  the   perineal  site  to  the  caudal  ventral  abdomen.    Urinary  continence  is  maintained,  but   one  complication  is  ascending  urinary  tract  infections.    Both  animals  showed   evidence  of  ascending  urinary  tract  infection  following  this  procedure,  and  the  goat   was  euthanized  due  to  stricture  formation  at  the  new  site.
Bladder  marsupialization  is  another  surgical  option  that  is  typically  a  one-­‐ time  procedure,  thus  shortening  hospital  time  and  expense, 10  and  was  originally   used  as  a  salvage  procedure  when  financial  constraints  were  present.
22    The  success   rate  for  this  procedure  has  been  reported  to  be  80%.
22,23    In  a  retrospective  study  of
19  goats  receiving  bladder  marsupialization  as  treatment  for  obstructive
10

urolithiaisis, 22  seven  goats  had  urethrostomy  previously,  and  one  had  three   cystotomies  in  conjunction  with  urethrostomies,  so  the  bladder  marsupialization   was  used  as  a  salvage  procedure  in  this  case.    This  procedure  is  typically  performed   under  general  anesthesia,  using  two  paramedian  incisions.    The  first  incision  is  used   to  locate  the  bladder  and  bring  it  to  the  ventral  body  wall  for  cystotomy,  and  the   second  incision  is  used  as  the  marsupialization  site.    The  bladder  is  secured  to  the   site  by  suturing  the  seromuscular  layer  of  the  bladder  to  the  abdominal  fascia  at  the   incision,  followed  by  suturing  the  cystotomy  margins  to  the  skin.    One  complication   that  has  been  reported  in  virtually  all  patients  after  bladder  marsupialization  is   urine  scald,  however  the  owners  still  remain  satisfied  with  the  procedure.
22,23    Other   complications  encountered  with  bladder  marsupialization  include  cystitis,   ascending  urinary  tract  infection,  and  bladder  mucosal  prolapse.
22,23    One  recent   case  study  reported  success  using  a  laparoscopic  surgical  technique  to  perform   bladder  marsupialization  on  a  goat  that  had  recurrent  urethral  obstruction   following  perineal  urethrostomy.
26    The  authors  reported  minimal  signs  of   postoperative  pain,  and  conclude  that  the  laparoscopic  technique  as  a  sound   alternative  to  traditional  laparotomy  techniques  for  bladder  marsupialization.
Postoperative  complications  still  included  urine  scald,  just  the  same  as  other   marsupializations  –  but  recovery  postoperatively  was  quicker  and  with  less  pain  as   perceived  by  the  authors.
The  prognosis  for  goats  with  obstructive  urolithiasis  varies  depending  on  the   severity  of  the  obstruction,  and  treatment  selected.    In  general,  prognosis  remains   fair  to  guarded  as  recurrence  is  likely.    If  conservative  treatment  fails,  then  long-­‐ term  prognosis  is  guarded  to  poor.
2    One  retrospective  study  found  that  serum   potassium  concentration  <5.2  mg/dL,  no  fluid  in  abdomen  and  intact  urethral   process  at  time  of  admission  were  associated  with  a  higher  likelihood  of  survival.
10
The  same  study  concluded  that  prognosis  for  survival  following  tube  cystotomy  was   good,  up  to  several  years.    The  reason  long  term  prognosis  is  poor  is  most  often  due   to  the  incomplete  clearance  of  calculi  within  the  urethra,  and  stricture  formation  in   the  urethra  due  to  irritation  and  pressure  necrosis  that  results  in  recurrent   obstruction.
14    A  retrospective  study  reviewing  45  cases  of  male  goats  with
11

obstructive  urolithiasis  compared  percutaneous  tube  cystotomy,  surgical  tube   cystotomy,  and  bladder  marsupialization  as  treatment  options,  and  found  that  there   was  not  any  difference  between  the  three  treatments  for  time  to  mortality,  but  that   percutaneous  tube  cystotomy  was  associated  with  more  complications  and  need  for   a  second  intervention  compared  to  the  other  two  procedures.
12    It  has  also  been   reported  that  the  presence  of  free  abdominal  fluid  and  intact  urinary  bladders  is   poorly  correlated  with  successful  outcome  after  tube  cystotomy.
12    This  may  be  due   to  the  longer  duration  of  obstruction  resulting  in  leakage  of  fluid  from  the  bladder,   and  perhaps  more  pronounced  electrolyte  abnormalities.
12
Obstructive  urolithiasis  is  a  serious  problem  that  commonly  affects  pet  goats.
Once  the  urolithiasis  occurs,  it  is  difficult  to  manage,  so  prevention  is  key.    Dietary   management  is  likely  the  most  important  method  to  prevent  recurrence  of   urolithiasis.    Pet  goats  should  receive  high  quality,  free  choice  mixed  alfalfa  and   grass  hay  with  salt  and  trace  minerals.
2    Water  should  be  available  at  all  times  in   excess  to  encourage  increased  urine  volumes.
2  The  calcium  phosphorus  ration   should  be  2:1  to  2.5:1.
2    In  one  clinical  trial,  ammonium  chloride  administered  to   male  castrated  yearling  goats  at  a  dose  of  450mg/kg  or  2.25%  of  DMI  resulted  urine   pH  of  <6.5  for  24  hours.
16    These  goats  were  being  fed  orchard  grass  hay,  so  the   results  of  ammonium  chloride  administration  may  be  different  with  other  diets.
Ammonium  chloride  is  unpalatable,  resulting  in  decreased  owner  compliance,  as  it   is  more  difficult  to  encourage  goats  to  consume  this  supplement.
16    Side  effects  of   ammonium  chloride  supplementation  in  goats  have  not  been  documented,  however   osteopenia  has  been  reported  in  sheep  with  dietary-­‐induced  metabolic  acidosis, 17   and  in  dogs  and  cats  it  has  been  shown  to  increase  urinary  calcium   concentration.
18,19    Fractional  excretion  of  calcium  was  increased  in  goats  being   treated  with  ammonium  chloride  in  the  clinical  trial,  but   the  authors  believe  that  the   decreased  urine  pH  due  to  the  increased  urinary  chloride  excretion  may  offset  the   risk  of  calcium  carbonate  urolith  formation  due  to  the  acidic  pH.
16
Delaying  castration  is  also  another  preventive  strategy,  however  breeding   can  occur  at  3  months  of  age  so  this  is  not  always  practical  from  a  management
12

standpoint.
2    Therefore,  dietary  management  is  key  to  prevent  future  obstructive   urolithiasis.
Case  Report
The  patient  presented  as  a  20-­‐month-­‐old  castrated  Nigerian  Dwarf  goat  with   a  one-­‐day  history  of  stranguria.    Prior  to  presentation,  the  referring  veterinarian   amputated  the  urethral  process  and  passed  a  urinary  catheter,  but  obstructive   uroliths  were  not  visualized,  and  the  patient  continued  to  strain.    The  referring   veterinarian  performed  serum  chemistry  revealing  normal  creatinine,  BUN,  sodium,   potassium  and  chloride  values,  whereas  phosphorus  was  decreased  (2.8  mg/dL;   reference  range  4.2  –  7.6).
On  presentation ,  the  patient’s  vitals  were  within  normal  limits.    Packed  cell   volume  (PCV)  and  total  solids  (TS)  were  35%  and  6.6  g/dL,  respectively.    A  venous   blood  gas   revealed  azotemia,  hyperglycemia,  and  a  normochloremic  metabolic   alkalosis.     Ionized  calcium  was  decreased,  and  lactate  was     mildly   elevated.    The   azotemia  likely  had  both  pre-­‐  and  post-­‐renal  components,  as  the  patient  had   evidence  of  a  urinary  obstruction,  and  was   assessed  to  be  moderately  dehydrated  as   well.    Hyperglycemia  was  likely  to  due  stress.    The  most  common  acid-­‐base   abnormality  in  these  cases  is  hypochloremic  metabolic  alkalosis.
21    It  is  possible  that   the  duration  of  obstruction  in  this  case  was  not  long  enough  to  see  the  decreased   chloride  levels.    The  decreased  calcium  is  associated  with  urinary  tract  obstruction,   but  the  pathogenesis  is  not  clearly  understood.
28    The  slight  elevation  in  lactate  may   have  been  due  to  tissue  damage  and  ischemia  secondary  to  urinary  obstruction.
Survey  radiographs  were  performed  at  admission,  but  did  not  reveal  any   radiopaque  stones.    The  patient  was  sedated  with  diazepam,  and  a n   ultrasound   guided  percutaneous  bladder  catheter  was  placed   to  relieve  the  pressure  caused  by   the  suspected  obstruction.    Once  the  catheter  was  in  place,  a  large  amount  of   sanguineous  fluid  with  sediment  was  drained  through  the  catheter.    Intravenous   fluid  therapy  was   started   using  Lactated  Ringer’s  Solution  (LRS)  at  a  rate  of  250   mL/hr.      The  patient  was  prescribed  Naxcel  (2.2  mg/kg)  subcutaneously  every   twelve  hours  in  case  of  secondary  urinary  tract  infection,  and  Banamine  (25  mg  IV)
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every  twelve  hours  for  the  first  day,  to  be  decreased  to  once  daily  thereafter  as   needed  for   analgesia .
The  following  morning ,  the  patient’s  vitals  were  stable,  and  urine  was   draining  freely  from  the  catheter.    Blood  glucose  and  lactate  were  re-­‐evaluated  at   this  time  and  found  to  be  in  the  normal  reference  range.    PCV  and  TS  decreased
(30%  and  6.2  g/dL  respectively),  likely  due  to  hemodilution  secondary  to  fluid   therapy.    At  this  time  the  plan  was  to  monitor  the  patient’s  catheter  to  ensure  urine   continued  to  drain  freely  for  two  days,  then  attempt  clamping  the  catheter  to  assess
the  patient’s  ability  to  urinate  normally.
The  patient  remained  stable  during  those  two  days  and  urine  drained  freely   from  his  catheter.    When  the  urinary  catheter  was  clamped,  the  patient  strained  to   urinate,  and  the  catheter  was  unclamped  later  that  same  day  due  to  the  distention  of   his  urinary  bladder.    Urine  dipstick  test  revealed  a  pH  of  8.5,  and  large  amounts  of   blood .     The  decision  was  made  to  delay  discharge  to  allow  his  urethra  to  heal.
Ammonium  chloride  (10  grams  PO  SID)  was  added  to  his  treatment  protocol  to   acidify  his  urine  with  the  goal  of  dissolving  uroliths  currently  present  in  his  urinary
bladder,  and  preventing  the  formation  of  new  ones.
For  an  additional  three  days,  the  patient  was  managed  with  the  percutaneous   urinary  catheter.    Banamine  was  discontinued  on  the  second  day.    The  patient’s   vitals  remained  stable,  and  his  urine  pH  decreased  to  6.0  over  this  period  of  time,   indicating  a  positive  response  to  the  ammonium  chloride.    The  catheter  was  again   clamped  on  the  third  day  to  evaluate   the  p atient’s  ability  to  urinate  on  his  own,  and   once  again  he  strained  and  the  catheter  had  to  be  unclamped  to  allow  his  bladder  to   drain.    At  this  time,  surgical  options  (perineal  urethrostomy  and  bladder   marsupialization)  were  discussed.    The  patient  was  given  an  additional  three  days   with  the  unobstructed  percutaneous  catheter  to  encourage  urethral  healing.    During   this  time  his  urine  pH  remained  at  6.0,  but  when  the  catheter  was  capped  once  again   the  patient  strained  to  urinate,  and  the  decision  was  made  to  perform  the  perineal   urethrostomy.
On  the  eleventh  day  of  the  patient’s  hospitalization,  a  perineal  urethrostomy
(PU)  was  performed  without  immediate  complications.    The  percutaneous  catheter
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was  clamped  the  evening  of  the  surgery,  and  trace  amounts  of  diluted  blood  and   urine  drained  from  red  rubber  catheter  in  the  patient’s  urethra  the  following   morning.    The  patient’s  vitals  remained  stable,  and  he  was  noted  to  have  an   excellent  appetite  following  the  surgical  procedure.    Naxcel  and  ammonium  chloride   were  continued  at  the  same  dosages.    The  percutaneous  catheter  was  removed  the   day  following  the  PU  operation,  and  no  complications  were  noted.    The  red  rubber   catheter  was  removed  from  the  patient’s  urethra  on  the  second  day  following   surgery,  and  the  patient  was  monitored  to  confirm  normal  urination  without  blood   before  he  was  discharged  from  the  hospital.
The  patient  was  discharged  on  the  fifth  day  following  his  PU.    At  this  time,  the   owners  were  educated  regarding  the  dietary  changes  necessary  to  prevent  future   obstructive  calculi  from  forming.    The  owners  were  instructed  to  feed  a  high   roughage  diet  composed  of  good  quality  alfalfa/grass  hay  and  provide  access  to   fresh  water  at  all  times.    Trace  minerals  were  recommended  to  increase  the   patient’s  thirst  and  encourage  him  to  drink  more  water.    Ammonium  chloride  (10   grams  SID)  was  prescribed  for  maintenance  of  lower  urine  pH.    At  the  time  of   discharge,  the  patient’s  penile  stump  occasionally  dripped  some  bloody  discharge   but  his  urination  was  normal.
A  recheck  examination  was  performed  approximately  one  month  following   the  patient’s  discharge,  and  the  PU  site  was  healing  appropriately.    The  owners   reported  the  patient  was  urinating  normally  at  that  time.
The  patient  presented  three  months  following  the  PU  for  progressive   stranguria.
T he  patient  was  bright,  alert,  and  responsive  with  normal  vitals  with  the   exception  of  panting.    The  patient  was  dripping  and  spraying  a  fine  mist  of  urine   from  his  urethrostomy  site  that  was  7/8ths  obstructed  due  to  stricture  from  scar   tissue  formation  at  the  site.    Ultrasonographic  examination  revealed  a  severely   distended  bladder.    The  patient  was  sedated  with  xylazine,  and  a  “Tom  Cat”  urinary   catheter  was  passed  with  4  mL  of  lidocaine  through  the  PU  site  into  the  bladder.
190  mL  of  urine  was  evacuated  using  a  60  mL  syringe,  followed  by  passing  the   smallest  Foley  catheter  and  aspirating  an  additional  60  mL  of  urine.    Finally  the   second  smallest  urinary  catheter  (5  french)  was  passed  through  the  PU  site  into  the
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bladder,  and  was  tacked  with  4-­‐0  suture  to  be  removed  in  four  days.      The  patient   was  hospitalized  for  a  total  of  four  days.    On  the  day  prior  to  discharge,  the  PU  site   was  opened  using   scissors  following  application  of  local  anesthetic,  and  the  sutures   holding  the  catheter  in  place  were  reinforced.    Patient  was  given  a  dose  of  Nuflor
(900  mg)  to  provide  four  days  of  antibiotic  coverage  in  case  of  infection.       The   patient  remained  stable  during  this  time,  and  the    catheter  was  removed  four  days   following  discharge  as  directed.
One  week  following  removal  of  the  catheter,  the  patient   re-­‐ presented  with   stranguria  once  more .     The  patient  was  anesthetized  with  isofluorane,  and  a  “Tom
Cat”  catheter  was  placed,  sutured,  and  Patient  was  sent  home.    Over  the  course  of   the  next  six  months,  the  stricture  at  the  PU  site  was  managed  by  replacing  urinary   catheters  under  general  anesthesia,  using  the  largest  bore  size  that  would  fit   through  the  stricture.    Nine  catheters  were  used  over  the  course  of  six  months,  but   the  stricture  remained.    Approximately  nine  months  following  the  first  PU   it  was   decided  a  second  PU  operation  was  necessary  and  the  owners  consented.
The  patient’s  PU  revision  occurred  approximately  9  months  following  the   original  operation.    During  the  operation,  the  penis  was  brought  more  superficially   and  sutured  to  more  superficial  subcutaneous  tissues  compared  to  the  previous   operation  in  hopes  of  preventing  stricture  formation.    The  surgery  was  performed   with  only  minor  hemorrhage  following  incision  into  the  urethra  that  was  controlled   later  with  compression  and  ice  packs.    The  site  was  rechecked  two  weeks  following   the  procedure,  and  was  noted  to  be  healing  well  at  that  time.
Three  months  following  the  PU  revision  (1  year  after  first  PU),  the  patient   presented  with  a  two  hour  history  of  stranguria.    On  physical  exam,  the  patient’s   pulse  and  respirations  were  mildly  elevated,  and  dripping  urine  was  noted  from  his
PU  site.    Patient  was  anesthetized  to  allow  placement  of  a  urethral  catheter  to  check   for  obstructing  calculi,  but  none  were  discovered.    There  was  not  any  evidence  of   stricture  formation  either,  so  cystitis  was  the  presumed  diagnosis  and  the  patient   was  treated  accordingly  with  Naxcel  (2.2mg/kg)  administered  subcutaneously  twice   daily  for  five  days.
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Five  days  later,  the  patient  presented  to  the  hospital  again  for  decreased   urine  flow  and  stranguria.    The  day  before  presentation  the  owners  noticed  the   patient  had  a  depressed  attitude.    The  patient  had  been  receiving  ammonium   chloride  twice  daily,  but  was  receiving  5-­‐  6  grams  once  daily  for  a  period  of  time,   and  again  increased  to  twice  daily  prior  to  presentation  as  reported  by  the  owners.
During  this  time  he  was  being  fed  grass  hay  and  no  grain.    On  physical  exam,  the   patient’s  pulse  and  respirations  were  markedly  elevated  (192  beats/min  and  72   breaths/min).    The  patient  was  actively  straining  to  urinate  while  standing.
Ultrasound  exam  of  the  bladder  revealed  a  dilated  bladder  (about  6.5  cm)  with   sludge  sitting  on  the  ventral  aspect.    At  this  time,  the  patient  was  placed  under   general  anesthesia,  a  catheter  was  passed,  and  his  bladder  was  flushed  with  2  liters   of    sterile  saline.
Six  months  later,  the  patient  presented  to  the  hospital  due  to  inability  to   urinate  for  one  day.    The  owners  reported  the  patient  had  been  recently  moved  to  a   new  pasture,  and  did  not  drink  as  much  as  usual,  perhaps  due  to  the  new   surroundings.  The  patient’s  bladder  was  flushed  at  the  hospital  the  previous  day,   and  he  returned  due  to  lack  of  improvement.    On  physical  exam  the  patient’s  vitals   were  within  normal  limits,  and  he  was  dribbling  urine.    Ultrasound  exam  revealed  a   distended  urinary  bladder,  approximately  13  cm  in  diameter.    On  dipstick  exam,   urine  pH  was  6.0  with  large  amounts  of  blood  present.    Glucose  was  negative.
Abdomen  was  tense  on  abdominal  palpation.    A  venous  blood  gas  revealed mild   acidemia  with  metabolic  acidosis,  mild  hyponatremia  and  hyperchloremia.    PCV  and
TS  were  38%  and  6.5  g/dL,  respectively.    The  urine  specific  gravity  was  1.010,  and   the  culture  and  susceptibility  results  indicated  a  gram  postitve  cocci.    A  urethral   catheter  (5  French)  was  placed  under  general  anesthesia,  and  the  urethra  and   bladder  were  flushed  with  saline.      The  following  day,  a  larger  catheter  (8  French)   was  placed  and  the  urethra  and  bladder  were  infused  with  Walpole’s  solution   to   decrease  urinary  pH  and  dissolve  the    uroliths  present  in  the  bladder .    Ultrasound   exam  that  day  revealed  a  smaller  bladder  with  debris  floating  inside.    Urine  pH  was   reduced  to  5.0  after  the  infusion  of  Walpole’s  solution.    The  bladder  size  on   ultrasound  the  following  day  was  still  small,  with  improvement  of  the  amount  of
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debris  in  the  bladder.    During  his  hospitalization,  the  patient  received  37.5  mg  of
Banamine  IV,  Naxcel  (2.2  mg/kg)  SQ,  and  8  grams  of  ammonium  chloride  PO  daily.
Salt  slurries  were  administered  as  needed  to  encourage  thirst.    Before  discharge
(four  days  after  admission),  the  patient  also  received  a  dose  of  Excede  (200  mg)  to   treat  the  urinary  tract  infection  that  was  to  be  repeated  in  four  days.    The  discharge   instructions  to  the  owners  emphasized  the  importance  of  daily  administration  of  8   grams  of  ammonium  chloride  for  the  remainder  of  the  patient’s  life.    The  urinary   catheter  was  to  remain  intact  for  3-­‐5  days  before  removal.
Two  days  following  discharge  the  patient  returned  to  the  hospital  unable  to   urinate.    On  presentation,  he  was  panting  and  excessively  vocalizing.    Again,   ultrasound  revealed  a  distended  bladder,  so  he  was  anesthetized  and  his  urethra   and  bladder  were  catheterized.    A  calculus  was  identified  in  the  urethra,  but  several   attempts  were  unable  to  remove  the  stone.    A  red  rubber  catheter  to  allow  urine   outflow  that  was  to  remain  in  place  for  8-­‐10  days.    Patient  was  prescribed  Excede
(200  mg  SQ  once  daily)  for  four  days,  and  the  continuation  of  ammonium  chloride  (8   grams  PO  SID)  administration.    The  patient  stayed  in  the  hospital  for  two  days,  then   returned  home  once  more.
Approximately  ten  days  later  the  patient  returned  to  the  hospital  with   stranguria  and  hematuria  as  the  presenting  complaint.    The  urethral  catheter  was   slipping  out,  and  had  to  be  shortened  as  a  result.    The  hematuria  was  present  for   approximately  five  days  prior  to  presentation,  but  the  patient’s  attitude  and  appetite   remained  normal.  Vital  parameters  were  within  normal  limits,  with  the  exception  of   a  slightly  elevated  pulse.    On  physical  exam,  Patient  was  straining  and  drips  of  urine   were  coming  from  the  catheter.    PCV  and  TS  were  30%  and  7.0  g/dL  respectivley.
The  patient’s  third  PU  was  performed  under  general  anesthesia  to  relieve  the   obstruction  in  his  urethra.    The  patient  received  Banamine  (40  mg  SQ/IV  twice   daily)  for  the  first  two  days  following  the  operation  to  control  pain.    Excede  was  also   administered  (200  mg  SQ),  and  was  to  be  repeated  every  four  days  for  two   additional  doses.    Patient  was  discharged  with  the  same  instructions  to  the  owners   regarding  dietary  management  of  urolithiasis  to  prevent  future  reobstructions.
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Three  days  following  the  operation,  the  patient  presented  due  bleeding  from   his  PU  site.    The  owners  first  noted  the  patient  urinating  in  a  split  stream  without   any  blood  or  straining,  then  on  the  morning  five  days  following  the  operation  the   owner  noted  bleeding  near  the  incision  site  that  did  not  stop,  and  ranged  from  drops   to  a  steady  stream  of  blood.    On  presentation,  his  hind  end  was  covered  in  blood,   and  blood  clots  were  present  from  near  the  incision  site  to  both  hind  limbs.    The   surgeon  inspected  the  site,  and  found  the  patient  to  be  quite  painful  near  his  tail,   and  located  an  arterial  bleeder  near  the  incision  site.    The  surgeon  determined  the   site  itself  was  intact,  and  a  10  French  catheter  was  easily  passed,  indicating  a  patent   urethra.    To  slow  the  bleeding,  silver  nitrate  sticks  were  applied  to  the  area.    The   patient  was  hospitalized  for  a  total  of  six  days.    PCV  and  TS  were  monitored  during   this  time.    The  values  at  admission  were  30%  and  5.8  g/dL,  and  decreased  to  15%   and  5.5g/dL  on  day  four  of  hospitalization,  the  same  day  in  which  the  bleeding  from   the  artery  started  again.    The  patient  was  placed  under  general  anesthesia  for   periurethrostomy  artery  ligation,  which  was  successfully  completed.    At  this  time,   buccal  mucosal  bleeding  time  (BMBT)  was  assessed  and  found  to  be  within  normal   limits,  indicating  normal  primary  hemostasis.    Following  the  operation,  Patient   received  Banamine  for  pain  management,  and  Excede  to  prevent  infection.    On  the   sixth  day,  the  patient  was  discharged  from  the  hospital  urinating  normally.
The  patient  returned  to  the  hospital  approximately  two  months  following  his   third  PU  operation  for  suture  removal.    The  owner  reported  that  the  patient  was   doing  very  well  at  home,  had  a  great  appetite,  and  was  urinating  normally  without   any  difficulty.    After  the  sutures  were  removed  from  the  PU  site,  the  patient  was  sent   home  without  any  further  treatment  necessary.
This  case  illustrates  the  long,  difficult  management  of  obstructive  urolithiasis   in  pet  goats.    The  owners  of  this  goat  were  exceptional  in  the  amount  of  time  and   finances  they  allotted  to  the  treatment  of  this  problem—this  is  not  typical  of  many   cases.    It  is  of  the  opinion  of  the  author  that  repeat  perineal  urethrostomy  or  bladder   marsuplializaiton  earlier  in  the  course  of  the  disease  may  have  been  appropriate   once  stricture  formation  became  an  issue  as  opposed  to  repeat  catheterizations  in   an  attempt  to  manage  the  stricture  formation.    PU  revision  does  not  guarantee  the
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abolishment  of  stricture  formation,  but  may  have  been  more  effective  than   catheterization.    Bladder  marsupialization  was  another  option  for  this  patient  in   response  to  stricture  formation.    However,  urine  scald  is  a  postoperative   complication  that  affects  relatively  all  cases  and  would  have  to  be  accepted  and   managed  by  the  owner.    The  relapse  in  the  patient’s  condition  that  occurred  after  his   water  consumption  and  ammonium  chloride  dose  was  temporarily  decreased   clearly  demonstrated  the  importance  of  dietary  management  in  the  face  of   obstructive  urolithiasis  –  regardless  of  the  surgical  or  medical  procedures   performed,  obstruction  will  reoccur  if  diet  is  not  managed  properly.
Obstructive  urolithiasis  is  a  common,  difficult  problem  in  pet  goats.
Preventive  dietary  management  should  be  encouraged  to  those  owners  to  prevent
this  disease  process,  as  it  has  such  a  poor  long-­‐term  prognosis  once  it  is  initiated.
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