G

G

G symbol for giga; gingival; glucose; gonidial; guanine.

g 1. gravity; the unit of force exerted upon a body during acceleration and deceleration. 2. gram (or grams).

γ gamma, small letter; third letter in the Greek alphabet.

G banding the technique of demonstrating g bands.

G bands in cytogenetics the pattern of bands produced by staining the chromosomes with Giemsa after fixing the proteins to prevent them binding with dye.

G-CSF granulocyte-colony stimulating factor.

G protein a regulatory protein which becomes activated when bound to GTP and is involved in signal transduction.

G. p. coupled receptor a member of a large class of cell-surface signaling receptors that contain seven transmembrane a helices; ligand binding results in activation of a coupled trimeric G protein that then initiates intracellular signal transduction pathways.

G₁ phase, G₁ period see cell cycle.

G₂ phase, G₂ period see cell cycle.

G6PD glucose-6-phosphate dehydrogenase.

Ga chemical symbol, gallium.

GABA γ-aminobutyric acid.

gabapentin [gab″-pen′tin] anticonvulsant and analgesic. Originally designed to be a structural analog of gamma-aminobutyric acid, although its anticonvulsant properties are now known to be unrelated to this property. When used as an analgesic, gabapentin seems to be particularly useful in the treatment of pain of neurogenic origin.

Gadd technique a modification of the episioplasty procedure for second degree perineal lacerations. A triangular piece of mucous membrane is removed from the dorsal vestibule. The vestibular mucosa is then apposed, then the perineal body is reconstructed with a series of interrupted absorbable sutures, before the skin is closed.

gadding [gad′ing] restlessness and excitement in horses, to a lesser extent cattle, because of the presence of biting flies, more specifically warble flies in cattle and bot flies in horses.

gadolinium (Gd) [gad″o-lin′e-m] a chemical element, atomic number 64, atomic weight 157.25. See Table 4.

Gaertner’s canal see Gartner’s ducts.

gag [gag] 1. a device for holding the mouth open. See also mouth speculum. 2. to retch, or strive to vomit.

mouth g. (1) see Drinkwater mouth gag, Haussman gag, spring gag (below), Varnell gag, probang.

g. (2) reflex elevation of the soft palate and retching elicited by touching the back of the tongue or the wall of the pharynx; called also pharyngeal reflex.

spring g. a gag used in dogs to keep the mouth open during treatment of teeth. It consists of two bars which run up and down a curved pillar. The bars have perforated disks at their ends, into which a canine tooth can be positioned. Pressure on the disks jams the sliding action of the bars.

gag gene [gag] a gene which encodes precursors of internal virion proteins found in the retroviral genome.

Gage excavator [gāj] a long, thin, handheld instrument consisting of a handle, a thin neck and a slightly curved, rounded blade that slips between the vertebrae and scoops out degenerated disk material. Used in the fenestration of intervertebral disks in dogs.

gagging [gag′ing] the swallowing–vomiting activity of the gag reflex.

gaggle collective noun for a group of geese.

GAGs glycosaminoglycans.

Gaigeria [ga-je′re-] a genus of hookworms in the family Ancylostomatidae.

G. pachyscelis occurs in the duodenum of the goat and sheep. A voracious blood-sucker and an infestation of as few as 24 can be fatal.

gain [gān] increase in body weight. See also growth rate, gain ratio.

average daily g. (ADG) the average gain in bodyweight of the animal. Usually expressed in kg, g, or lb/day. ADG stated for bulls at sale are for measured gains in tests of 140 or 160 days in length.

feed cost of g. total feed cost divided by total pounds of gain.

gait [gāt] the manner or style of locomotion. Often used in assessing horses and dogs. See also ataxia, dysmetria, incoordination, spastic, stringhalt, walk, trot, canter, gallop (2), cadence, five-gaited.

g. analysis evaluation of the manner or style of walking, usually done by observing the animal as it walks or trots in a straight line. The normal forward step consists of two phases: the stance phase, during which one or more legs and feet are bearing most or all of the body weight, and the swing phase, during which the other feet are not touching the walking surface and the body weight is borne by the others. In a complete two-step cycle all feet are in contact with the ground at the same time for about 25% of the time. This part of the cycle is called the double-support phase. An analysis of each component of the three phases of ambulation is an essential part of the diagnosis of various neurological disorders and the assessment of patient progress during rehabilitation and recovery from the effects of a neurological disease, a musculoskeletal injury or disease process, or amputation of a lower extremity.

antalgic g. a limp adopted so as to avoid pain on weight-bearing structures, characterized by a very short stance phase.

asymmetric g. refers to right-left symmetry of leg movements; in the horse, canter and gallop.

ataxic g. an unsteady, uncoordinated walk, employing a wide base.

base-wide g. feet are wider apart than normal, suggesting instability. Seen with cerebellar ataxia.

diagonal g. one in which a forelimb is moved in unison with its opposite hindlimb, e.g. trot.

double-step g. a gait in which there is a noticeable difference in the length or timing of alternate steps.

high stepping g. may be normal in some fancy gaited horses. In others it may be a sign of blindness or poor proprioception, usually because of a defect in the sensory nervous system. It may also be a manifestation of hypermetria.

G-1: Spring gag.

From Sonsthagen TF, Veterinary Instruments and Equipment: A Pocket Guide. 2nd Edition. Mosby, 2011.

horse g. there are three natural gaits, walk, trot, canter and two artificial gaits, the foxtrot, rack. There are a number of other less well-defined gaits similar to foxtrot.

spastic g. a walk in which the legs move in a stiff manner, the toes seeming to drag and catch.

symmetric g. leg movements on one side are repeated on the other side; in the horse, walk, trot, pace.

waddling g. exaggerated alternation of lateral trunk movements with an exaggerated elevation of the hip, suggesting the gait of a duck.

gaited [gāt’d] see five-gaited.

Gal galactose.

GAL virus Gallus adeno-like virus; the Aviadenovirus genus.

galactagogue [g-lak’t-gog] 1. promoting the flow of milk. 2. An agent that promotes the flow of milk.

galactans [g-lak’tns] an ingredient of the toxins of some Mycoplasma spp.

galactemia [gal″ak-te′me-] the presence of milk in the blood.

galactic [g-lak′tik] 1. pertaining to milk. 2. galactagogue.

galactischia [gal″ak-tis′ke-] suppression of milk secretion.

galact(o)- word element. [Gr.] milk.

galactoblast [g-lak′to-blast] a colostrum corpuscle in the acini of the mammary gland.

galactobolic [g-lak″to-bol′ik] of or relating to the action of neurohypophyseal peptides which contract the mammary myoepithelium and cause ejection of milk.

galactocele [g-lak′to-sēl] 1. a milk-containing, cystic enlargement of the mammary gland. 2. hydrocele filled with milky fluid.

galactocerebrosidase an enzyme that catalyzes the hydrolytic cleavage of galactose from galactocerebroside. Deficiency results in accumulation of galactocerebroside in tissues (globoid cell leukodystrophy). Called also galactosylceramidase, galactosylceramide β-galactosidase.

galactocerebroside [g-lak″to-s-re′bro-sīd″] a glycosphingolipid with a galactose unit. Called also galactolipid. See globoid cell leukodystrophy.

galactocerebrosidosis see globoid cell leukodystrophy.

galactography [gal″ak-tog’r-fe] radiography of the mammary ducts after injection of a radiopaque substance into the duct system.

galactokinase [g-lak″to-ki’nās] an enzyme that catalyzes the first step in the metabolism of galactose, the transfer of a phosphate group from ATP to galactose, producing galactose-1-phosphate.

g. deficiency see galactosemia.

galactolipid, galactolipin [g-lak″to-lip′id, g-lak″to-lip′in] see galactocerebroside.

galactoma [g-lak″to’m] galactocele (1).

galactophore [g-lak′to-for] 1. galactophorous. 2. a milk duct.

galactophoritis [g-lak″to-for-i′tis] inflammation of the milk ducts.

galactophorous [gal″ak-tof′o-rs] conveying milk.

galactophygous [gal″ak-tof’-gs] arresting the flow of milk.

galactoplania secretion of milk in some abnormal part.

galactopoiesis [g-lak″to-poi-e′sis] the production of milk by the mammary glands.

galactopoietic [g-lak″to-poi-et′ik] 1. pertaining to, marked by, or promoting milk production. 2. an agent that promotes milk flow.

galactorrhea [g-lak″to-re’] excessive or spontaneous milk flow; persistent secretion of milk irrespective of nursing; lactorrhea. May occur in dogs with severe hypothyroidism due to hyperprolactinemia, pseudocyesis, or trauma to the mammary gland.

galactosamine [gal″ak-to’s-mēn] an amino derivative of galactose.

galactose [g-lak’tōs] a monosaccharide epimer of glucose. D-galactose is found in lactose, cerebrosides of the brain, raffinose of the sugar beet, and in many gums and seaweeds; L-galactose is found in flaxseed mucilage.

g. 1-phosphate uridylyl transferase enzyme involved in the metabolism of galactose to glycogen. Congenital galactosemia of humans and macropods is associated with a deficiency of this enzyme.

g. tolerance test a laboratory test done to determine the liver’s ability to convert the sugar galactose into glycogen. Not much used in animals.

galactosemia [g-lak″to-se′me-] a biochemical disorder in which there is a deficiency of enzymes necessary for proper metabolism of galactose. The condition is inherited in humans in two forms, due to deficiency of either galactokinase or galactose-1-phosphate uridyltransferase. Adult macropods are normally deficient in these enzymes. Normally the sugar derived from lactose in milk is changed by enzymatic action into glucose. When the conversion of galactose to glucose does not take place, the galactose accumulates in the tissues and blood, typically causing cataract formation; commonly seen in young macropods reared on cow’s milk.

G-2: Cataract in a young kangaroo fed cow’s milk that resulted in galactosemia.

From Maggs DJ, Miller PE, Ofri R, Slatter’s Fundamentals of Veterinary Ophthalmology, 4th Edition. Saunders, 2008.

galactosidase [g-lak″to-si’dās] an enzyme that catalyzes the conversion of galactoside to galactose; it occurs in two forms: α-galactosidase (melibiase) and β-galactosidase (lactase). In deficiency states gangliosides (galactose-containing cerebrosides) accumulate in tissues. See also GM¹ gangliosidosis.

β-galactosidase [g-lak″to-si’dās] a lysosome hydrolase catalyzing the β-gangliosides into monosaccharides.

galactoside [g-lak′to-sīd] a glycoside containing galactose.

galactosis [gal″ak-to′sis] the formation of milk by the lacteal glands.

galactostasis [gal″ak-tos’t-sis] 1. cessation of milk secretion. 2. abnormal collection of milk in the mammary glands.

galactosuria [g-lak″to-su′re-] the presence of galactose in the urine.

galactosylceramidase [g-lak′to-sl“s-ram’-dās] see galactocerebrosidase.

galactosylceramide [g-lak′to-sl″ser’-mīd] see galactocerebroside.

galactosyl transferase [g-lak′to-sl″trans’fr-ās] an enzyme which contributes to glycolization.

galactotherapy [g-lak′to-ther’-pe] treatment of sucking neonates by medication given to the dam.

galacturia [g-lak″to-u′re-] chyluria; the discharge of urine with a milky appearance.

galah Australian bird, gray above, pink below. Noisy and a pest in grain crops because of large numbers. Called also Cacatua roseicapilla, roseate cockatoo.

Galanthus nivalis European plant in the family Liliaceae; bulbs cause salivation, vomiting and diarrhea. Called also snowdrop.

Galba the host snail genus for the intermediate stages of Fasciola hepatica in North America.

galea [ga′le-] pl. galeae [L.] a helmet-shaped structure.

g. aponeurotica aponeurosis connecting the frontal and occipital bellies of the primate occipitofrontal muscle.

g. capitis the cap over the head of the spermatozoon. Called also acrosomal vesicle.

g. glandis the diminutive caplike glans of the ruminant penis.

Galega officinalis European plant in the legume family Fabaceae; contains galegine, which causes sudden death from hydrothorax and pulmonary edema. Called also goats’ rue, French lilac or honeysuckle.

galena a mineral containing lead.

Galenia genus of African plants in family Aizoaceae; includes G. africana (geelbos, kraalbos)—contains an unidentified cardiotoxin which causes waterpens, a cardiomyopathy, liver fibrosis and ascites, and G. pubescens (green galenia)—may cause nitrate–nitrite poisoning.

galenicals [g-len’-klz] medicines prepared according to the formulae of Galen. The term is now used to denote standard preparations containing one or several organic ingredients, as contrasted with pure chemical substances.

Galeopsis a European genus of the plant family Lamiaceae. Seeds of these plants contain an unidentified toxin which causes anorexia, anasarca and jaundice. Includes G. ladanum. Called also hedge nettle, hemp nettle.

galeta grass Hilaria jamesii, commonly infested with Claviceps cinerea, which causes poisoning.

Galiceno small, solid-colored (any color) pleasure horse of Mexican origin.

Galician Blond cattle Spanish cream to red-brown meat cattle.

Galician sheep prolific Spanish meat and medium-wool sheep, mostly polled.

gall [gawl] 1. bile. 2. a sore caused by chafing; said commonly of horses. 3. an excrescence on a plant, e.g. on the seedheads of Lolium rigidum, caused by plant nematodes and causing poisoning. 4. an extract of galls. Used in medicine as a bitter.

girth g. see girth gall.

saddle g. see saddle sore.

g. sickness see anaplasmosis.

gallamine [gal’-mēn] a competitive neuromuscular blocking agent used as a muscle relaxant. Used as the triethiodide. It competes with acetylcholine for the cholinergic receptors at the postsynaptic membrane.

gallate [gal’āt] antioxidant used in food preservation, especially in foods containing oils and fats. Includes propyl, octyl and dodecylgallate.

gallbladder [gawl′blad″r] the pear-shaped reservoir for bile attached to the visceral surface of the liver or in a hollow between the quadrate and right medial lobes of the liver in all domestic animals except the horse. It serves as a storage place for bile. The gallbladder may be subject to such disorders as inflammation and the formation of gallstone.

g. cystic mucosal hyperplasia hyperplasia of the mucussecreting glands in the gallbladder and larger bile ducts. See also gallbladder mucocele.

g. edema a gross lesion in many cases of infectious canine hepatitis.

g. inflammation cholecystitis.

g. paralysis an abnormality seen consistently in lantadene poisoning. The gallbladder is paralyzed, grossly distended and full of viscid, pale bile.

porcelain g. intramural mineralization of the gallbladder.

g. radiography see cholecystography.

Gallibacterium genus of gram-negative bacteria associated with disease in birds.

G. anatis a cause of septicemia, peritonitis and salpingitis in chickens. Previously called Pasteurella anatis.

G. melopsittaci bacterial species isolated from cases of septicemia in parakeets and budgerigars and salpingitis in a parakeet.

G. salpingitidis bacterial species isolated from cases of salpingitis, peritonitis, airsacculitis and pneumonia in birds, and a case of pericarditis in a cat. Previously called Pasteurella salpingitis, Actinobacillus salpingitidis and atypical A. lignierisii.

G. trehalosiformentans bacterial species isolated from a case of septicemia in a budgerigar.

galliform see gallinaceous.

gallinaceous, galliform belonging to the genus Gallus, hence domestic and wild fowl.

gallium (Ga) [gal′e-m] a chemical element, atomic number 31, atomic weight 69.72. See Table 4.

g.-67 a radioisotope of gallium having a half-life of 78.1 hours; used in the imaging of soft tissue tumors.

g. nitrate used in the treatment of hypercalcemia.

g. scan a nuclear medicine procedure using the radioisotope gallium- 67 in the form of gallium citrate. Gallium has a high affinity for certain tumors and also for non-neoplastic lesions, such as abscesses. Gallium scans are particularly useful in the staging of lymphomas, and in localizing occult abscesses.

gallon [gal′on] a unit of liquid measure; the American gallon equals 4 quarts (3.785 liters) and the Imperial gallon equals 4.546 liters.

gallop [gal′op] 1. a disordered rhythm of the heart. See also gallop rhythm. 2. the horse’s fastest gait. All four hooves are off the ground at the one time and the rhythm is one of four beats. The sequence of contact by the hooves is near hind, off hind, near fore, then off fore (when the off fore is the leading limb).

diastolic g. see gallop rhythm.

gallotannic acid [gal″o-tan′ik] tannic acid.

Galloway a polled, black-brown breed of dairy cattle originating in Scotland. See also Belted Galloway.

G. pony a now extinct Scottish pony. Nowadays the term is used to identify a show class of pony which is greater than 14 hands high but not more than 14.2 hands high.

G-3: Galloway beef bull.

From SambrausHH, Livestock Breeds. Mosby, 1992.

gallstone [gawl′stōn] a stonelike mass that forms in the gallbladder. See cholelithiasis.

Gallus a genus of birds of the pheasant family Phasianidae. Includes the domestic fowl. See also fowl.

G. domesticus see Gallus gallus (below).

G. gallus the Red Junglefowl, the progenitor of the domestic fowl. Also the domestic fowl, itself sometimes called G. domestica.

GALT gut-associated lymphoid tissue.

Galt trephine a 0.75 inch cylinder with a saw-toothed cutting edge at one end and grinding ridges down the outside with a crossbar handle at the other end for excision of a plate of bone. The center of the cutting circle has a sharp-pointed pin which prevents the trephine from moving laterally while cutting and fixes the trephined bone disk so that it does not fall into a cavity.

Galtonia clavata see Pseudogaltonia clavata.

galtonian inheritance based on a multilocal system of character definition so that progeny present a continuous series of a characteristic rather than specific classes, e.g. a range of body weights rather than giants and dwarfs.

Galumna oribatid mites which act as intermediate hosts for Moniezia spp. (tapeworms).

galvanic current [gal-van′ik] a steady direct electric current.

galvanocontractility [gal“v-no-kon″trak-til’-te] contractility in response to stimulation by galvanic current.

galvanometer [gal“v-nom’-tr] an instrument for measuring current by electromagnetic action.

galvanopalpation [gal“v-no-pal-pa′shn] testing of nerves of the skin by means of galvanic current.

Galvayne’s groove a vertical goove in the labial surface of the upper corner permanent incisor tooth in the horse. It appears at the gum margin at 10 years of age, is halfway to the end of the tooth at 15 years, has reached the end at 20 years, has disappeared from the top of the tooth at 25 years and has disappeared completely at 30 years. The ages quoted are subject to variation.

Galway sheep polled, Irish meat and longwool sheep.

Gambardella technique a modification of the lateral imbrication approach to extra-articular reconstruction of the cranial cruciate ligament in dogs. Nonabsorbable sutures are placed between the distal patellar tendon and the proximal femorofabellar fascia and the lateral collateral ligament.

Gambee suture pattern a rapidly inserted, interrupted suture used to close a bowel anastomosis with one layer of stitches. The suture goes from serous to mucosal surface, back into the mucosa on the same side of the incision, out into the middle of the cut surface to be approximated, across the incision into the wound edge opposite, down into gut lumen, back through the mucosa and through the wall to the serous surface and a tie with the tail of the suture across the incision.

Gambian sleeping sickness [gam′be-n] see Trypanosoma gambiense.

Gambierdiscus toxicus [gam″be-r-dis’ks] marine dinoflagellate; the main source of toxins responsible for ciguatera.

gambrel the bracket-shaped piece of iron rod on which a sheep carcass is traditionally hung to cool and set.

Gambusia [gam-boo′se-] small, 1 inch long, pale fish which eat mosquito larvae and are used in their control. Called also topminnows or mosquitofish.

Game broad-breasted, brightly colored breed of table poultry used widely in breeding hybrid table poultry.

game [gām] birds or animals hunted and killed in the chase, i.e. for sport. Used also in respect of animals hunted for provisions and skins. Said of animals and birds, hence game birds, etc.

g. animals includes deer and other similar large ruminants, wild pig and the group of largely African animals classed as ‘big game’. Game fish are marlin, tuna and other big marine fish rather than the smaller freshwater fish of rod and reel devotees.

g. birds birds originally hunted but nowadays also farmed. Includes pheasants, quail, partridge, francolin, jungle fowl, guinea fowl.

g. farm farm dedicated to keeping game animals, usually exotic ones, in the wild in conditions as nearly natural as possible. In most instances they are a hobby or for relaxation and entertainment. They are really private zoos or zoological gardens.

g. fish fish hunted for sport.

g. meat meat from slaughtered game animals.

g. ranch see game farm (above).

Game cock closest domestic fowl variety to the ancestral Red Junglefowl. Used in cockfighting. A tall, upright, gaudily colored bird with a fearsome hooked beak and spurs. The head and neck and tail coverts are bright yellow, the back and the wings are brown, the breast is black. The beak is brown and the feet are slate-colored.

game theory a branch of mathematical logic which deals with all of the possible reactions to a particular strategy used mainly in systems analysis.

gamefowl [gām′foul] see game cock.

gamete [gam’ēt] a haploid germ cell; one of two cells, male (spermatozoon) and female (ovum), whose union is necessary in sexual reproduction to initiate the development of a new individual.

gametocyte [g-me′to-sīt] an oocyte or spermatocyte; a cell that produces gametes.

gametogenesis [g-me″to-jen’-sis] the development of the male and female sex cells (gametes).

gametogony [gam″-tog’-ne] 1. the development of merozoites into male and female gametes, which later fuse to form a zygote. 2. reproduction by means of gametes.

gamma [gam’] 1. the third letter of the Greek alphabet, Γ or γ. 2. used in names of chemical compounds to distinguish one of three or more isomers or to indicate the position of substituting atoms or groups.

g. benzene hexachloride see chlorinated hydrocarbons.

g. delta T lymphocyte see T lymphocyte.

gamma camera see scintillation camera.

Gamma–Gandy body, Gandy–Gamma nodule an organizing, minerlizing focus of stagnant blood, deposited usually on the margins of a chronically congested spleen. Called also siderotic nodule.

gamma subunit third-named chain (or subunit) occurring in the functional organization of macromolecules, usually proteins, containing three or more chains.

gammaglobulinopathy [gam″-glob“u-lin-op’-the] see gammopathy.

Gammaherpesvirinae [gam″-hur“pēz-vir-i′ne] one of three subfamilies within the family Herpesviridae, comprising the following genera: Lymphocryptovirus, Macavirus, Percavirus, Rhadinovirus, and many unassigned viruses.

Gammaretrovirus [gam″-ret′ro-vi“rs] a genus of the family Retroviridae. Many species contain oncogenes and cause sarcomas and leukemias. Examples are murine leukemia virus, feline leukemia virus, feline sarcoma virus, and avian reticuloendotheliosis viruses. Many endogenous retroviruses, closely related to exogenous gammaretroviruses, are present in the DNA of mammals (including humans), birds, reptiles and amphibians.

Gammarus water crustaceans; intermediate hosts for Tetrameres spp. nematodes.

gammexane see lindane.

gammopathy [gam-op’-the] abnormal proliferation of the B lymphocytes resulting in abnormal concentrations of immunoglobulin production; the gammopathies include multiple myeloma, macroglobulinemia and Hodgkin’s disease. Called also gammaglobulinopathy.

biclonal g. characterized by two narrow-based peaks, usually in the γ region; may indicate a neoplastic production of immunoglobulin.

monoclonal g. an increased production of one type of immunoglobulin by a single clone of cells. The abnormal protein produced is called paraprotein or M component and may be composed of whole immunoglobulin molecules or subunits, light-chains (Bence Jones proteins) or heavy-chains. Occurs in myelomas, lymphoproliferative neoplasms, and occasionally chronic inflammatory or immune-mediated diseases. Greatly elevated serum concentrations of protein may result in a hyperviscosity syndrome.

polyclonal g. a hypergammaglobulinemia resulting from an increased production of several different immunoglobulins and usually attributable to persistent, high level exposure to antigens; occur in a wide variety of infectious, inflammatory, and immunemediated diseases. Examples in animals are feline infectious peritonitis, canine ehrlichiosis, Aleutian mink disease and equine infectious anemia.

gamogenesis [gam″o-jen’-sis] sexual reproduction.

gamont [gam′ont] gametocyte.

ganado bravo [Span.] see fighting bull.

ganciclovir [gan-si′klo-vir] a synthetic nucleoside analog of guanine with antiviral activity against herpesviruses, especially cytomegalovirus.

gander [gan’dr] a male goose.

ganglial [gang′gle-l] pertaining to a ganglion.

gangliated [gang′gle-āt″d] provided with ganglia; ganglionated.

gangliectomy [gang″gle-ek’t-me] excision of a ganglion; ganglionectomy.

gangliform [gang′gl-form] having the form of a ganglion.

gangliitis [gang″gle-i′tis] see ganglionitis.

gangli(o)- word element. [Gr.] ganglion.

ganglioblast [gang′gle-o-blast″] an embryonic cell of the cerebrospinal ganglia.

gangliocyte [gang′gle-o-sīt″] a ganglion cell.

gangliocytoma [gang″gle-o-si-to’m] see ganglioneuroma.

ganglioform [gang′gle-o-form″] gangliform.

ganglioglioma [gang″gle-o-gli-o’m] a glioma rich in mature neurons or ganglion cells.

ganglioglioneuroma [gang″gle-o-gli″o-n -ro’m] see ganglioneuroma.

ganglioma [gang″gle-o’m] see ganglioneuroma.

ganglion [gang′gle-on] pl. ganglia, ganglions [Gr.] 1. a knot or knotlike mass; a general term to designate a group of nerve cell bodies, located outside the central nervous system. Occasionally applied to certain nuclear groups within the brain or spinal cord, e.g. basal ganglia. 2. simple ganglion.

aorticorenal g. small sympathetic ganglia supplying nerve fibers to the kidneys.

Arnold’s g. see otic ganglion (below).

autonomic g. aggregations of cell bodies of neurons of the autonomic nervous system; the parasympathetic and the sympathetic ganglia combined.

basal g. subcortical masses of gray matter embedded in each cerebral hemisphere, comprising the corpus striatum (caudate and lentiform nuclei), amygdaloid body and claustrum. Other structures such as the substantia nigra have also been considered to be part of the basal ganglia. Called also basal nuclei.

cardiac g. ganglia of the superficial cardiac plexus found close to the aortic arch.

celiac g. two large sympathetic ganglia, found on either side of the celiac artery, supplying nerve fibers to the viscera supplied by that artery; sensory and parasympathetic fibers also pass through the ganglia.

cephalic g. parasympathetic ganglia in the head, consisting of the ciliary, otic, pterygopalatine and submandibular ganglia.

cerebrospinal g. those associated with the cranial and spinal nerves.

cervical g. 1. any of the three ganglia (cranial, middle and caudal) of the sympathetic trunk found near the base of the skull and inside the thoracic inlet. 2. one near the cervix uteri.

cervicothoracic g. a ganglion on the sympathetic trunk formed by a union of the caudal cervical and one or more thoracic ganglia. Called also stellate ganglion.

ciliary g. a parasympathetic ganglion in the posterior part of the orbit supplied by the oculomotor nerve.

Corti’s g. spiral ganglion.

dorsal root g. spinal ganglion.

false g. an enlargement on a nerve that does not have a true ganglionic structure.

gasserian g. trigeminal ganglion.

geniculate g. the sensory ganglion of the facial nerve, on the geniculum of the facial nerve.

g. impar the single ganglion commonly found where the caudal limits of the sympathetic trunks of the two sides unite.

jugular g. 1. the proximal ganglion of the vagus nerve. 2. the proximal (superior) ganglion of the glossopharyngeal nerve.

lumbar g. the ganglia on the lumbar part of the sympathetic trunk.

otic g. a parasympathetic ganglion next to the medial surface of the mandibular nerve, just ventral to the foramen ovale. Its postganglionic fibers supply the parotid gland. Called also Arnold’s ganglion.

parasympathetic g. aggregations of cell bodies of cholinergic neurons of the parasympathetic nervous system; these ganglia are located near to or within the wall of the organs being innervated.

petrous g. the distal ganglion of the glossopharyngeal nerve.

pterygopalatine g. a parasympathetic ganglion in a fossa in the sphenoid bone, formed by postganglionic cell bodies that synapse with preganglionic fibers from the facial nerve via the nerve of the pterygopalatine canal. Called also sphenopalatine ganglion.

sacral g. those of the sacral part of the sympathetic trunk.

semilunar g. trigeminal ganglion.

sensory g. any of the ganglia of the peripheral nervous system that transmit sensory impulses; also, the collective masses of nerve cell bodies in the brain subserving sensory functions.

simple g. a cystic tumor in a tendon sheath.

sphenopalatine g. pterygopalatine ganglion.

spinal g. ganglia on the dorsal root of each spinal nerve.

spiral g. the ganglion on the cochlear nerve, located within the modiolus, sending fibers peripherally to the organ of Corti and centrally to the cochlear nuclei of the brainstem. Called also Corti’s ganglion.

stellate g. cervicothoracic ganglion.

sympathetic g. aggregations of cell bodies of adrenergic neurons of the sympathetic nervous system; these ganglia are arranged in chainlike fashion on either side of the spinal cord.

thoracic g. the ganglia on the thoracic portion of the sympathetic trunk.

trigeminal g. a ganglion on the sensory root of the fifth cranial nerve. Called also gasserian ganglion and semilunar ganglion.

tympanic g. an enlargement on the tympanic branch of the glossopharyngeal nerve.

vestibular g. the sensory ganglion of the vestibular part of the eighth cranial nerve, located in the dorsal part of the lateral end of the internal acoustic meatus.

Walther’s g. ganglion impar.

Wrisberg’s g. cardiac ganglia.

ganglion blocking [gang′gle-on] blocking of transmission through the autonomic ganglia.

autonomic g. b. agents substances such as nicotine which block transmission across sympathetic ganglia by blocking the nicotinic receptors in the ganglion, reducing transmission to about 20% of normal.

synthetic g. b. agents include methonium compounds (e.g. hexamethonium, trimethidinium) and other unrelated compounds, e.g. mecamylamine. Have the advantage of avoiding side-effects of nicotine.

ganglionated [gang′gle--nāt″d] provided with ganglia; gangliated.

ganglionectomy [gang″gle--nek’t-me] excision of a ganglion; gangliectomy.

ganglioneuritis [gang″gle-o-n -ri′tis] see ganglionitis.

ganglioneuroma [gang″gle-o-n -ro’m] a rare benign neoplasm composed of nerve fibers and ganglion and Schwann cells. Generally, these occur in dogs, intracranially in the brain or cranial nerve ganglia, or rarely in the adrenal medulla or autonomic ganglia. See also neuroblastoma.

ganglionic [gang″gle-on′ik] pertaining to a ganglion.

g. blockade inhibition by drugs of nerve impulse transmission at autonomic ganglionic synapses.

g. blocking agent see ganglion blocking.

ganglionitis [gang″gle--ni′tis] inflammation of a ganglion; gangliitis.

myoenteric g. causes chronic intestinal pseudoobstruction in horses.

ganglionostomy [gang″gle--nos’t-me] surgical creation of an opening into a cystic tumor on a tendon sheath or aponeurosis.

ganglioplegic [gang″gle-o-ple′jik] 1. blocking transmission of impulses through the sympathetic and parasympathetic ganglia. 2. an agent that so acts.

ganglioradiculitis [gang″gle--r-dik“u-li′tis] inflammation of spinal ganglia and nerve roots. Clinical signs in affected dogs include sensory deficits, ataxia, hypermetria, megaesophagus, dysphonia and Horner’s syndrome. Siberian huskies are predisposed.

ganglioside [gang′gle-o-sīd″] a class of galactose-containing cerebrosides found in central nervous system tissues; they are glycolipids of the basic composition ceramide-glucose-galactose- N-acetyl neuraminic acid. The form GM¹ accumulates in tissues in generalized gangliosidosis as observed in Friesian cattle, dogs and cats. The form GM² accumulates in a similar disease of Yorkshire pigs, dogs and cats.

gangliosidosis [gang″gle-o-si-do′sis] a group of inherited lipid storage disorders marked by accumulation of gangliosides in tissues due to an enzyme defect. Characterized by progressive neuromuscular dysfunction and impaired growth from an early age.

GM1 g. a defect of β-galactosidase which causes accumulation of galactoside GM¹. Identified in Friesian cattle, Suffolk sheep, dogs and cats.

GM2 g. a defect of hexosaminidase A in dogs and pigs, and hexosaminidase A and B in cats. Analogous to the similar diseases in humans, which are called also Sandhoff’s disease, Tay–Sachs disease and Bernheimer–Seitelberger disease. In Burmese cats, a mutation of hexoaminadase β-subunit (HEXB) gene is an autosomal recessive trait. Affected cats show mild tremors and progressive neurological dysfunction starting at an early age.

gangrene [gang′grēn] the death of body tissue, generally in considerable mass, usually associated with loss of vascular (nutritive) supply, and followed by bacterial invasion and putrefaction. Although it usually affects the extremities, gangrene sometimes may involve the internal organs. Signs depend on the site and include fever, pain, darkening of the skin, and an unpleasant odor. If the condition involves an internal organ, it is generally attended by pain and collapse.

dry g. occurs only in the extremities, and usually because of gradual diminution of the blood supply. Signs include gradual shrinking of the tissue, which becomes cold and lacking in pulse, and turns first brown and then black. Bacterial decomposition is slowed by the dryness of affected tissue.A sharp line of demarcation is formed where the gangrene stops, owing to the fact that the tissue above this line continues to receive an adequate supply of blood.

gas g. results from dirty lacerated wounds infected by anaerobic bacteria, especially species of Clostridium. It is an acute, severe, painful condition in which muscles and subcutaneous tissues become filled with gas and a serosanguineous exudate.

internal g. in strangulated hernia, a loop of intestine is caught in the bulge and its blood supply is cut off; gangrene may occur in that section of tissue. Thrombosis of the mesenteric artery may result in gangrene of a section of intestine. Gangrene can be a rare complication of lung abscess in pneumonia.

G-4: Gangrene of the ear tips and snout in a pig with erysipelas.

moist g. occurs rapidly in deep tissues that cannot dry out; a result of ischemic necrosis followed by saprophytic bacterial putrefaction.

segmental g. gangrene of a section of an organ, e.g. of part of an elephant’s ear, as a result of sectional compromising of blood supply.

gangrenous [gang’r-ns] pertaining to, marked by, or of the nature of gangrene.

g. cellulitis gangrenous necrosis of the skin of the thorax and thighs of chickens of 1–4 months of age caused by Clostridium septicum and other clostridia. Most affected birds die and the mortality rate in a flock may be as high as 60%. Called also necrotic dermatitis, gangrenous dermatitis.

g. coryza see malignant catarrhal fever.

g. dermatitis see gangrenous cellulitis (above).

g. ergotism see ergotism.

Ganjam virus a member of the family Bunyaviridae, genus Nairovirus causing a tickborne virus infection of sheep and goats in India.

ganskweek see Lasiospermum bipinnatum.

gantho metho Senecio raphanifolius.

gantho metho ajang Senecio biligulatus.

gap junctions [gap] regions of high and special ionic permeability between closely apposed cells. They are places at which cells exchange molecules of large size and provide an avenue by which developing cells can influence each other. Called also nexus.

neuronal g. j. very tight contacts between some neurons permitting the almost instant transmission of impulses from one neuron to the other; structural elements extend across the gap conferring a continuity of cytoplasm between the cells.

gape [gāp] a behavioral response shown by cats in recognition of urine odor. After sniffing, the cat flicks the tongue against the hard palate, opens its mouth, licks the nose, and has a fixed gaze. This may be similar to the flehmen reaction.

gapes [gāps] see Syngamus trachea.

gapeworm [gāp’wrm] see Syngamus trachea.

garbage-eating scavenging by dogs and cats involving ingestion of spoiled food, excessive quantities of unusual foods, and bones, resulting in gastroenteritis.

garbancillo Astragalus wootoni.

garbanzo [gahr-bahn′zo] see chickpea.

gare long, hairy, non-serrated fibers in the fleece of some crossbred sheep; usually in breech wool; the fibers cannot be dyed or spun.

gargaloo Parsonsia eucalyptophylla.

garget [gahr’gt] 1. mastitis. 2. Phytolacca americana.

gargoylism [gahr′goil-iz-m] mucopolysaccharidosis I; Hurler’s syndrome.

garland flower [gahr’lnd] see Daphne.

garlic [gahr′lik] Allium sativum.

Canada g. Allium canadense.

crow g. Allium vineale.

false g. Allium vineale.

three-cornered g. Allium triquetrum.

wild g. Allium ursinum, A. vineale.

wood g. Allium ursinum.

garron a type of large, sturdy pony bred in Scotland; originated in cross between Percheron and Highland pony. Also used generally to describe the native ponies of Scotland and Ireland.

Gartner’s ducts [gahrt’nr] remnants of the embryonic mesonephric ducts, sometimes found on the floor of the vagina, which often open into the vestibule.

cystic G. d. cystlike structures in the floor of the vagina.

gas [gas] any elastic aeriform fluid in which the molecules are widely separated from each other and so have free paths.

alveolar g. the gas in the alveoli of the lungs, where gaseous exchange with the capillary blood takes place. See also oxygen, carbon dioxide.

blood g. see blood gas analysis.

g. bubble disease a disease of fish in tanks in which the water is supersaturated with oxygen or nitrogen. Gas embolism develops in the gills. Air bubbles can be seen in the gills, eyes and under the skin and the fish show bizarre neurological behavior.

g. cap a cap of gas above fluid or solid contents in a hollow viscus, e.g. in a static rumen. Seen radiologically in distended intestinal loops in paralytical ileus.

g. edema disease see blue wing disease.

g. exchange gases move by simple diffusion in response to pressure differences; net diffusion occurs from areas of high pressure to areas of lower pressure irrespective of whether the gas is present as a gas or in solution or gases moving from gas to solution or vice versa. The rate of exchange of gases in body tissues, e.g. between alveolar space and erythrocyte, is influenced by many other factors, especially the diffusion distance and the solubility of the gas.

laughing g. nitrous oxide.

g. transport relates to the efficiency of transport of gas, e.g. oxygen, by the patient as a whole. The efficiency of gas transport varies widely between normal individuals and between species, e.g. athletic breeds of horses and dogs have much faster gas transport systems than human athletes; the efficiency of gas transport in the individual depends largely on the rapidity of increase in minute ventilation, plus a similar rate of increase in cardiac output.

g. tube see Crookes’ tube.

gaskin [gas′kin] the muscular portion of the hindleg between the stifle and hock, corresponding to the human calf. The term is used in horses and sometimes dogs.

gasoline poisoning see oil products.

gasping disease [gas′ping] see avian infectious bronchitis.

gasserian ganglion [g-se′re-n] see trigeminal ganglion.

gaster [gas’tr] [Gr.] see stomach.

gasterophiliasis gasterophilosis.

gasterophilosis the disease caused by infestation with Gasterophilus spp. Sporadic cases of abscess formation, even rupture of the stomach wall with local peritonitis, occur but the infestation, though dramatic, is virtually nonpathogenic.

Gasterophilus [gas“tr-of’-ls] a genus of flies, the horse bot flies, the larvae of which develop in the gastrointestinal tract of horses and may sometimes infect humans. A member of the family Gasterophilidae.

G. equi see G. intestinalis (below).

G. haemorrhoidalis eggs are laid around the mouth and on the cheeks; the larvae are found in the mucosa of the tongue and establish finally in the stomach.

G. inermis eggs are laid around the mouth and on the cheeks; the larvae are found in the cheek mucosa and settle finally in the rectum.

G. intestinalis (syn. G. equi) the eggs are laid near the front fetlocks and up the legs as far as the shoulder; the larvae are found in the mucosa of the tongue and subsequently at the gastric cardia.

G. nasalis (syn. G. veterinus) the larvae are laid in the intermandibular space; larvae are found at the pylorus and in the duodenum.

G. nigricornis an uncommon horse bot fly.

G. pecorum the eggs are laid on plants; larvae are found in the mucosa of the cheeks and eventually gastric pylorus.

G. veterinus see G. nasalis (above).

gasteropod see gastropod.

Gasterosteus a genus of fish, commonly known as sticklebacks. studied extensively in the fields of evolutionary biology, ecology, behavior and genomics.

gastradenitis inflammation of the gastric glands.

gastralgia [gas-tral’j] pain in the stomach; gastric colic.

gastrectasis distention of the stomach.

gastrectomy [gas-trek’t-me] excision of the stomach (total gastrectomy) or a portion of it (partial or subtotal gastrectomy).

gastric [gas′trik] pertaining to, affecting, or originating in the stomach.

g. acid see gastric juice (below).

g. atony a large distended stomach lacking in tone as seen in a horse that is a windsucker and continuously swallows air. Predisposes to chronic indigestion.

g. cicatricial contraction in horses causes constriction of the stomach and subsequent dilatation of the dorsal sac.

g. dilatation see gastric dilatation colic.

g. dilatation–displacement see gastric dilatation–volvulus (below).

G-5: Gastric dilatationvolvulus in a dog.

From van Dijk JE, Gruys E, Mouwen JMVM, Color Atlas of Veterinary Pathology, 2nd Edition. Saunders, 2007.

g. dilatation–volvulus (GDV) a syndrome of gastric dilatation leading to volvulus, seen most often in deep-chested, large breed dogs. The etiology is unclear, but aerophagia or overeating are important factors. Gastric hemorrhage and ulceration, hypotensive, hypovolemic shock, and severe electrolyte disturbances contribute to the highmortality. Surgical intervention is often required, cardiac dysrhythmias complicate recovery, and recurrences are common. Called also gastric dilatation–displacement, bloat.

g. distention in pigs commonly results in vomiting.

g. edema an accompaniment of edema in most organs in cases where edema is widespread; as a sole lesion is significant in the abomasum in cases of arsenic poisoning, ostertagiasis and in edema disease in pigs.

g. emptying time the time taken for the stomach to begin to empty of contents; demonstrated in contrast radiography. Delayed in gastric retention due to dysfunction of the pylorus, abnormalities of gastric motility, foreign bodies and systemic diseases.

g. fluid see gastric juice (below).

g. folds folds in the gastric mucosa and part of the submucosa oriented in the direction of the long axis of the stomach, as they are in the abomasum; they may be few and simple or numerous and tortuous, as in the dog.

g. foreign body occurs most commonly in dogs, causing vomiting. Occasionally it may pass into the small intestine, causing partial or complete obstruction with more severe signs of dehydration, shock, and sometimes perforation with peritonitis. A variety of objects may be swallowed, e.g. needles, balls, children’s toys, bones, fish hooks and socks, to name a few.

g. habronemiasis see habronemiasis.

g. hemorrhage caused by gastric ulcer or foreign body. May cause sudden death due to exsanguination, as in pigs with esophagogastric ulcer, or anemia with melena.

g. hormones see gastrointestinal hormones.

g. impaction in horses fed a diet of coarse indigestible roughage; a cause of subacute colic.

g. inhibitory polypeptide (GIP) a tentative gut hormone secreted by the mucosa of the small intestine and playing a part in controlling gastric (inhibition) and intestinal (stimulation) secretion and insulin release (stimulation).

g. intubation see intubation.

g. invagination a technique for gastric resection in which areas of nonviable gastric wall are folded inward and the remainder sutured together so the necrotic tissue sloughs into the gastric lumen.

g. juice the secretion of glands in the walls of the stomach for use in digestion. Its essential ingredients are pepsin, an enzyme that breaks down proteins in food, and hydrochloric acid, which destroys bacteria and is of assistance in the digestive process.

g. motility varies between the three regions of the stomach, being most active in the antrum, has a basic slow wave motility and a capacity to increase in response to the fullness of the stomach and to decrease with a rise in acidity of the duodenal contents.

g. mucosa secretes pepsin (as pepsinogen), hydrochloric acid.

g. neoplasia includes adenocarcinoma (most common in dogs), carcinoma, benign adenomatous polyps, leiomyomas, plasmacytoma, squamous cell carcinoma and lymphosarcoma (most common in cats).

g. outlet obstruction see pyloric obstruction, pyloric outflow failure, gastric retention syndrome.

g. peptidases includes pepsin A, trypsin, chymotrypsin, elastase, carboxypeptidase A, carboxypeptidase B.

g. perforation in horses occurs secondarily to lesions of the stomach wall, especially squamous cell carcinoma; causes a local peritonitis, often with extension to the spleen; in calves as a result of abomasal ulceration. Peritonitis inevitably follows.

g. pits multiple, densely distributed small depressions or crevices over most of the stomach mucosa; a gastric gland opens into the bottom of each pit.

g. protectant a substance used to protect gastric mucosa from injury, usually the risk of ulceration due to underlying disease or the effects of medication such as aspirin or nonsteroidal antiinflammatory drugs. Includes sucralfate and the histamine H²-receptor antagonists.

g. rotation rotations of the stomach in the embryonic abdomen between its first appearance and its final disposition. In simplestomached animals such as dogs two rotations are recognized, from the axial tube ventrally and to the left.

g. rupture causes sudden cessation of abdominal pain caused by distention; acute endotoxic shock and peracute, diffuse peritonitis kill the animal within a few hours.

g. squamous-cell carcinoma the commonest gastric neoplasm in horses. Seen usually in the advanced stages of anorexia and weight loss. Characterized by a fungating mass in the pars esophagea often with secondary implants locally, sometimes widespread in other organs.

g. torsion in sows, predisposed by large, sloppy meal and great excitement at feeding time leading to very fast eating. There is a short course with death due to shock and infarction of the stomach wall. See also gastric dilatation–volvulus (above).

g. ulcer an ulcer of the inner wall of the stomach. It occurs in all species at a low level but causes little disease. There is a high prevalence in horses racing and in training and is thought to result in impaired appetite. In horses, also caused by nonsteroidal antiinflammatory drugs. Called also gastric mucosal ulceration. Gastric ulcer is a common disease in housed pigs, manifest with hyperkeratinization and ulceration in the pars esophagea of the stomach. If an ulcer erodes to a blood vessel, the pig can become anemic or bleed to death. In affected herds, a significant proportion of pigs develop hyperkeratosis and ulceration but only a proportion show clinical disease. Risk factors include housing and stocking density, the use of pelleted feeds and low fiber and small particle size of feed.

g. venous infarction occurs in many septicemias, viremias and toxemias in horses and especially pigs; called also gastric mucosal infarction.

g. waves peristaltic waves, the pacemakers for antral peristalsis.

gastricism gastric disorder.

gastricsin [gas-trik′sin] a proteolytic enzyme isolated from gastric juice; its precursor is pepsinogen but differs from pepsin in molecular weight and in the N terminal amino acid.

gastrin [gas′trin] a polypeptide hormone secreted by certain cells of the pylorus, which strongly stimulates secretion of gastric acid and pepsinogen, and weakly stimulates secretion of pancreatic enzymes and gallbladder contraction.

g. assay serum concentration is elevated in dogs and cats with gastrinomas, other gastronintestinal disease and chronic renal failure.

gastrinoma [gas″tr-no’m] a gastrin-secreting, non-beta islet cell tumor of the pancreas, seen mainly in aged dogs and cats, associated with Zollinger–Ellison syndrome.

G-6: Gastric ulceration in the abomasum of a cow.

From van Dijk JE, Gruys E, Mouwen JMVM, Color Atlas of Veterinary Pathology, 2nd Edition. Saunders, 2007.

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Tags: Saunders Comprehensive Veterinary Dictionary

Jul 18, 2016 | Posted by admin in PHARMACOLOGY, TOXICOLOGY & THERAPEUTICS | Comments Off

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