Growth and Development I

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Growth and DevelopmentI

• AnS 224
• Spring 2009

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Pups and Kittens at Birth

• Eyes and ears closed
• Begin to open about 10-17 days
• Unable to urinate or defecate on their own
• Require maternal cleaning/stimulation
• Must be done by foster parent
• Unable to maintain body temperature
• Require adequate environmental support
• Localize to pups
• The pyramid versus twos and threes versus solo

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Early Newborn Period Mistaken folk wisdom

• Every litter has a runt (not necessarily true)
• Runting can be associated with some genetic
  diseases and these pups will be poor doers
• Runting is more likely to be a chance occurrence
• Where in the uterus did that pups placenta
  implant
• These pups should gain weight well, especially
  after the introduction of solid food
• Bitches sometimes accidentally smoother pups
• Look to something wrong with the pup or the dam
  or the housing and management of the litter

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Genetic DiseasesPuppy Growth and Development

• Early Newborn Period
• 1-3 days after birth
• Late Newborn Period
• Up to 2 weeks after birth
• Nursing Period
• Up to 3-4 weeks after birth
• Weanling Period
• 8 weeks after birth

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Early Newborn PeriodBirth deformity versus
metabolic disease

• Birth deformity
• Cleft palate or cleft lip
• Anus is not open, segmental atresia
• Walrus puppies
• Metabolic disease
• Fading puppies/dead puppies
• Acceptable losses are not necessarily natural
• May be difficult to distinguish true fading pups
  from management issues

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Congenital Malformations and Related Disorders

• Literally a defect present at birth
• Versus inherited disease
• Things that you can readily see at birth
• Can be recessive diseases
• Can be complex inheritance
• Not simple recessive/dominant
• Can also be spontaneous occurrence (new mutation
  not seen in parent)
• Some defects though present only show up
  clinically later

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Walrus Pups

• Anasarca
• Swelling of fetus with fluid
• Seen in various breeds and lines of dogs
• Multiple genetic causes
• Can cause life threatening dystocia

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Umbilical Hernia

• Cause unknown
• Genetics and environment
• If isolated, easily repaired
• No real impact on life and health
• More common in dogs than cats
• Use in breeding program?

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Ectodermal Dysplasia

• X-Linked Disease
• Spontaneous mutation in a male German Shepherd
• No hair over rump, head and chest
• Abnormal teeth and toe nails
• Evident at birth

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Coat Color Dilution

• Rhodesian Ridgeback color dilution syndrome
• Autosomal recessive, with lighter hair and iris
  than normal, and fatal brain disease
• Grey Collie Syndrome
• Autosomal recessive, lighter than normal hair,
  and fatal immune system defect

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Black Hair Follicular Dysplasia

• Pups have gray instead of black hair
• Hair begins to break and fall out at 2 weeks of
  age
• Affected dogs have normal white hair
• Affected adults are bald in black haired areas
• Autosomal recessive
• Normal parents with 25 affected pups
• Many breeds described

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Special Cases

• Merle
• One mutant allele
• Merle
• Two mutant alleles
• Defective White
• Deaf
• Eye problems
• Flashing in Boxers
• One mutant allele
• Flashed
• White nose, chest, and legs
• Two mutant alleles
• Defective White

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Late Newborn and Nursing Period

• Puppies should be stable and gaining 50 of body
  weight/week
• Possible problems if management adequate
• Herpes virus
• Can lose entire litters
• Will only happen once in a bitchs lifetime
• Navel ill
• Fading puppies and failure to thrive
• Metabolic disease

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Canine Herpes Virus

• Rare but serious clinical problem
• Understudied
• Virus prefers to replicate at lower than body
  temperature
• Cause of fatal infection in pups
• Can lose entire litter within days
• One time occurrence in the repro life of a bitch
• Caused by first time infection in perinatal period

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Immunodeficiency

• X-linked severe combined immunodeficiency
• (Bubble boy disease)
• Bassets
• Welsh Pembroke Corgis
• Normal females
• Produce only affected males
• Fading pups
• Failure to thrive
• 50 of normal weight
• Opportunistic infections and skin diseases
• Other forms may be possible, both X-linked and
  autosomal recessive

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Weanling Period

• Problems associated with feeding
• Mental dullness or seizures after eating
• Liver shunts
• Metabolic disease
• Regurgitation (throwing up food without the
  stomach contractions of vomiting)
• Megaesophagus
• Neurological disease

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Liver Shunts

• Blood bypasses liver
• Toxins not inactivated
• Low blood protein
• Low blood sugar
• Seen in cats and dogs
• Often mentally dull after feeding

http//www.acvs.org/AnimalOwners/HealthConditions/
SmallAnimalTopics/PortosystemicShunts(PSS
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Persistent Right Aortic Arch

• Abnormal vessels cause a ring around esophagus
• Seen in dogs when changing from liquid to hard
  food
• Difficult to manage
• Can be life threatening
• German shepherd dogs

http//cal.vet.upenn.edu/projects/cardiosf/project
/praapres/praprs3.htm
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Weanling Period

• Problems associated with urination
• Constant dribblers
• Blood in urine
• Difficult or painful urination
• Birth defects of the urinary tract
• Hydrocephalus
• Dome shaped head, wide spaced eyes, mentally dull

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Hydrocephalus
Think Chihuahua -domed shaped head -prominent
bulging eyes -severity varies -common
(normal) in some breeds
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Urinary Tract Deformities

• Vary in severity
• Some can be
• corrected surgically in some cases
• treated with drugs
• More common in dogs than cats
• More common in females than males

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Heart Defects

• Puppies born with heart murmur
• By weaning (7-8 weeks) not normal and bears
  watching (i.e. dont sell to uniformed owners)
• After six months consider a more serious
  condition