Anatomy & Physiology of the Pig

ANSC 4401Swine Production

Why understand pig A&P?

It will open new areas of application of pig biology to benefit humans

It helps you have a conversation with other pig people, veterinarians and scientists

It will help you manage pigs in meaningful ways on farmsRecognize disease states more easilyObtain blood or other tissue samples

Anatomy & Physiology Outline Anatomical terms Major bones Uses for pigs other than for eating Some terminology Blood collection Necropsy

Anatomical terms

Major bones of the pig

Uses of pigs other than for eating

Organ donors As a source of biological materials,

ex. Insulin or heparin As a model for biomedical research As an organ donor to humans For entertainment As pets As truffle-finders (they are smell

experts)

Xenotransplantation & Cloning

New pig cloning research promising yet risky, studies indicate

August 17, 2000

Web posted at: 12:57 PM EDT (1657 GMT)

WASHINGTON (CNN) -- Two groups of researchers publishing work in rival scientific journals report similar successes in cloning pigs -- a difficult process that may lead to ways to grow organs in the animals destined for human transplantation.

"The goal here is to reduce the shortage of organs for transplantation and prevent any more needless deaths that arise because people simply don't receive the organ they need," said Dr. Anthony Perry of New York's Rockefeller University.

Some Terms

Serum (fluid minus all cells and clotting factors)

Plasma (fluid including soluble clotting factors)

Red blood cells (obtained only from plasma)

White blood cells (obtained only from plasma)

Composition of Newborn Pigs

Table 1. Composition of newborns of three species and neonatal pigs.Data are percentage of total body weight.

Species Water Protein FatHuman, newborn 69.1 11.9 16.1Rat, newborn 86.0 10.8 1.1Pig, newborn 84.1 11.3 1.1Pig, 7 days old 68.5 13.6 9.5Pig, 28 days old 61.8 14.4 17.8From Widdowson, 1950 and Manners and McCrea, 1963.

Blood Collection From Pigs

Ear veinsJugular veinFacial veinTail veinOrbital Sinus

Points to sample from or inject into the venous system of pigs

Piglets Young pigs Adults1. Ventral Neck

Vena Cava External Jugular Lingual-facial difficult Facial difficult

2. Orbital sinus not advised

3. Ear vein difficult difficult

4. Tail vein difficult difficult

5. Heart (cardiac puncture) na* na* na* * not advised except as a last resort or in the case of euthanasiaPreferred method of restraint on backon back standing, snared

Common Bleeding Ports

External Jugular Vein

Auricular (ear) vein

Facial Vein

Orbital venous sinus

Bleeding Trough for Young Pigs

Bleeding tools: Vacutainer

Bleeding sows

Blood Collection Tubes

Table 2. Common blood collection tubes (tubes with * are commonly used)Color of tube top Fluid type Anticoagulant Example usesRed* Serum none Antibodies, minerals, other proteinsBlue Either Na heparin or none Special blood chemistriesBrown Plasma Na heparin Lead determinations & othersBlack/light blue Plasma Na citrate Coagulation studiesGray Plasma glycolytic inhibitors Glucose determinationsGreen* Plasma lithium heparin Na, Ca sensitive assaysYellow Plasma sodium citrate DNA extractionPurple/Lavender* Plasma EDTA Clotting factors

Maximum safe blood draw

Age & weightTotal blood volume, mL

Maximum draw, mL

Newborn, 3 lb 110 10

Nursery pig, 35 lb

1,280 120

Sow, 440 lb 16,000 1,600

Selected normal blood values

Measure ValueBlood volume 8 %WBC count 10-12 thousand/μLNeutrophils 45 %Lymphocytes 50 %Gamma globulin 25-30 mg/mL

Necropsy – Why?

To improve the herd health To contribute to the herd health

program To identify causes of illness or death

so that Effective treatments can be appliedPreventative measures can be

implemented

Necropsy – What to look for

Skin condition Swollen joints Wounds or abscesses Intestinal condition (fluid-filled, bloody, gas,

etc) Lung condition (hemorrhage, non-functional

tissues, edema, etc.) Liver condition (look for milk spots;

indication of a parasitic infection) Condition of other organs (kidneys, spleen,

heart) Snout condition (condition of the turbinates)

Necropsy – “normal”

Necropsy -- Tools

Scalpel Probes (spatula or equivalent) Saw (hack saw or equivalent) Water Mechanism to dispose of parts (plastic

bags)

The End