Canine Anatomy and Health: Reproductive, Urinary, and Digestive Systems

Comprehensive vocabulary flashcards covering canine reproductive surgeries, urinary tract anatomy and pathology, gastrointestinal ailments, and digestive system structure and motility.

Ovariohysterectomy

A surgical spay procedure performed under general anesthesia where both the uterus and ovaries are completely removed.

Ovarian Sparing Spay (OSS)

A surgical sterilization procedure that removes the uterus and cervix while retaining one or both ovaries, preventing pregnancy while preserving endogenous sex hormones.

Laparoscopic Spay

A minimally invasive surgical procedure performed through small incisions where the ovaries are excised while the uterus is left intact.

Castration (Orchidectomy)

A surgical neutering procedure performed under anesthesia in which both testicles and their associated structures are excised.

Suprelorin Implant

A subcutaneous implant providing temporary chemical castration in male dogs for a duration of up to $12\,\text{months}$.

Zeuterin

An intratesticular chemical sterilant composed of zinc gluconate neutralized by arginine that induces inflammation, fibrosis, and permanent sterility, showing $99.6\%$ efficacy in dogs aged $3-10\,\text{months}$.

Vasectomy

A surgical procedure in which the vas deferens are severed and sealed to block sperm transit to the urethra, preventing reproduction without reducing circulating testosterone levels.

Pyometra

A severe, life-threatening bacterial infection of the canine uterus resulting from cyclic hormonal changes that causes pus accumulation within the uterine horns.

Cryptorchidism

A congenital condition in male dogs characterized by the failure of one or both testes to descend properly into the scrotum.

Kidneys

Paired retroperitoneal organs located in the dorsal abdominal cavity surrounded by perirenal fat, responsible for filtering soluble metabolic wastes from blood and maintaining systemic homeostasis.

Renal Hilus

The medial indented depression of the kidney where the renal artery, renal vein, nerves, and ureter enter and leave the organ.

Renal Cortex

The outer histological layer of the kidney situated immediately deep to the fibrous renal capsule and peripheral to the renal medulla.

Renal Medulla

The inner zone of kidney tissue situated between the renal cortex and renal pelvis that contains the collecting ducts and loops of Henle.

Renal Pelvis

The funnel-like dilated proximal expansion of the ureter inside the kidney that collects urine delivered by the calyces.

Ureters

Fibromuscular tubes that transport urine from each renal pelvis to the urinary bladder, entering the bladder wall at an oblique angle to create a passive anti-reflux valve.

Trigone

The fixed triangular region on the dorsal floor of the urinary bladder delimited by the two ureteral openings and the internal urethral orifice.

Urethra

The tubular canal extending from the bladder neck through the pelvic cavity that conducts urine to the external environment, and additionally transmits semen in male dogs.

Transitional Epithelium

Specialized, highly distensible epithelial tissue lining the renal pelvis, ureters, urinary bladder, and urethra that stretches without cell rupture as fluid volume fluctuates.

Uroliths

Inorganic mineral concretions or stones that precipitate in the urinary tract, capable of producing urethral blockages, hydroureter, and renal compromise.

Gastric Dilatation-Volvulus (GDV)

A critical emergency syndrome where the canine stomach distends with gas or fluid (bloat) and rotates along its mesenteric axis (torsion), occluding gastric inflow and outflow.

Megaesophagus

A neuromuscular disorder characterized by generalized dilation and decreased or absent peristaltic motility of the esophagus, causing food and liquid stagnation.

Intestinal Parasites

Endoparasitic organisms inhabiting the canine gastrointestinal tract, including nematodes (roundworms, hookworms, whipworms), cestodes (tapeworms), and protozoa (Giardia, coccidia).

Heterodont Dentition

A dentition arrangement characteristic of canines possessing $4$ distinct tooth morphologies with specialized functions: incisors, canines, premolars, and molars.

Deciduous Teeth

The temporary primary dentition present in young domestic mammals, commonly referred to as milk teeth or baby teeth, which are later exfoliated and replaced by permanent teeth.

Monogastric Stomach

A single-chambered, C-shaped hollow digestive organ positioned immediately caudal to the diaphragm, divided into the cardia, fundus, body, pyloric antrum, and pylorus.

Rugae

Longitudinal microscopic and macroscopic folds in the gastric mucosa that flatten as the stomach fills, accommodating dietary volume.

Peristalsis

Coordinated wave-like contractions of longitudinal and circular smooth muscle layers that propel an ingesta bolus unidirectionally through the alimentary tract.

Segmentation

Rhythmic localized contractions of circular intestinal smooth muscle that blend chyme with enzymes and maximize mucosal contact without producing net forward transit.

Duodenum

The initial, short cranial segment of the small intestine that receives acidic chyme from the pylorus alongside biliary and pancreatic digestive secretions.

Liver

A large abdominal organ responsible for synthesizing bile, albumin, and coagulation factors, metabolizing amino acids, and detoxifying endogenous and exogenous compounds.

Defecation Reflex

An involuntary parasympathetic spinal reflex stimulated by distension of rectal mechanoreceptors that triggers colonic contraction and internal anal sphincter relaxation.