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there are pigs upstairs. so now we're getting to see pig anatomy. 
smallwood occasionally has diversions into the pig, and ch 34-38 in Dyce 
are on the pig. we can take a look at those. obviously this is totally 
unscheduled.

first of all, the external jugular is deep to a very thick platysma, so 
venipuncture of that vein would be very difficult, and you do the vena 
cava instead. also there is no nuchal ligament, it is instead like the 
cat. 

don't do muscular dissection. look at gi, gut, genitourinary...

there is a pharyngeal diverticulum which is dorsal to the esophagus. this 
is potentially clinically important because if you try to medicate the 
pig by mouth you could put the meds in the diverticulum instead of the 
esophagus if you aren't careful.

the thorax is unusual. the lungs go very far back, and actually lie 
outside of abdominal viscera for some distance. 

inguinal and scrotal hernias are common in pigs, their inguinal canals 
are quite large.

GI: this is not a ruminant. has a simple stomach, but there is a 
diverticulum on the fundus of the stomach. pigs are omnivores. the 
ascending colon because they are omnivores they do eat a lot of plant 
material the ascending colon is a spiral in a cone shape and then goes 
back in another spiral inside the first spiral cone. see the picture in 
smallwood or dyce. the outer or centripetal coil (inbound, opposite of 
cow) is sacculated, with two bands. the inner or centrifugal coil is 
outbound, opposite of cow, and is smooth. you could suture sacculated to 
smooth and skip part if you were doing surgery. 

the CECUM is of course before the ascending spiral colon. it is unusual 
because it is large and it lies on the left side of the pig. it's ventral 
to the descending colon. the coil of the spiral colon is attached to the 
dorsal body wall, btw. so it goes from dorsal to ventral.

urogenital: sow has 7 pairs of mammary glands, and one of the common 
surgeries is a caesarian delivery, in which case the cut is made dorsal 
to the abdominal mammary glands. abdominal wall muscles are flabby and 
hard to suture so you need to suture the fibrous layers between muscles. 
the ovaries are freely mobile in fact they are so mobile you may find 
them both lying against the same body wall. the uterus is again an 
unusual structure. it has very long horns, maybe a meter long, pigs have 
large litters of 8-10 piglets so... the uterus has a short body and a 
long cervix as well. cervix can be 25 cm long.  

the bladder in the pig is entirely in the abdomen.

male urogenital tract:the scrotum is just below the anus, more like a cat 
than other animals we've seen. the inguinal passage is large in diameter 
so hernias even into the scrotum are fairly common. most pigs - males- 
are castrated young because the presence of the testes affects the way 
the meat tastes. pet pigs are often castrated too because of smell and 
rowdiness. sex glands in male esp intact male are large. try to see them 
if we have boars. the vesicular gland is quite large, the bulbourethral 
gland is very large, in the intact male theseglands may touch eachother 
along the dorsal surface of the urethra. the prostate gland is 
comparatively small, partly disseminated in wall of urethra and not even 
seen externally.the thick urethralis muscle is around the urethra. 
prostate is ventral to the vesicular gland. the penis as in the ox or 
goat is a fibroelastic penis. it has a corkscrew twist in it as well as 
the sigmoid flexure common to all fibroelastic penises. there is also a 
diverticulum in the prepuce of the pig's penis which is dorsal to the 
free end of the penis and in which the tip of the penis may sometimes 
become entrapped so the poor pig can't get it out of there :(.

that's about it on the pigs. these are fresh animals, not fixed. 

oh, also, the kidneys, unlike other animals, are side by side and kind of 
dorsoventrally compressed. they lie against the dorsal body wall - right 
kidney doesn't touch the liver. they aren't staggered like usually - they 
lie NEXT TO each other.


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