Veterinary Assays and Controls

Veterinary Specific controls

 

CONTROLS	PACK SIZE	CAT NO (AUDIT)	CAT NO (GLENBIO)
GENERAL CHEMISTRY CONTROLS (LYO)	20x5ml.  NORMAL	AD922VET	GL922VET
GENERAL CHEMISTRY CONTROLS (LYO)	20x5ml.  ELEVATED	AD932VET	GL932VET
CANINE C-REACTIVE PROTEIN (CRP ) SET	20x1ml	AD909	GL909
EQUINE IGG CONTROL SET	2×0.3ml		GQC160
EQUINE FIBRINOGEN CONTROL	2×0.3ml		GLFIBCON2
TDM CONTROL  (L1&L2)	2x2x5ml	ADTD9111	GLTD9111

 

 

 

Veterinary Biochemistry Assays

Equine IGG

IgG is the major Immunoglobulin produced by the plasma cells. It accounts for 70 to 75% of the total Immunoglobulins. Its’ major function is of neutralisation of toxins and destruction or removal of infectious agents that is accomplished by initiating either phagocytosis or to compliment cascade.  IgG is measured by an immunoturbidimetric method.

This assay assesses of colostral transfer of immunity to the newborn foal. In a normal equine pregnancy, there is no transplacental transfer of IgG before birth. During the last few months of gestation, mares concentrate IgG in their colostrum. Foals intestines are capable of absorbing IgG for their first 12-18 hours of life. Serum samples should be taken from foals on the second day of life when IgG levels should ideally be >8 g/l.

 

 

Equine SAA

Serum amyloid A protein (SAA) was discovered in blood serum components as a precursor to the deposited protein (amyloid A protein) which occurs in secondary amyloidosis accompanying inflammatory diseases. SAA is synthesized by the liver, and its concentrations in the blood increase with infectious diseases, malignant tumors, autoimmune diseases, and tissue necrosis. Glenbio SAA assay is a reagent developed for highly sensitive and accurate measurement of SAA. This measurement utilises a latex agglutination reaction, and the change in turbidity caused by this reaction is measured optically to determine the concentration

Serum amyloid A (SAA) is the major acute phase protein in horses. It is produced during the acute phase response, a nonspecific systemic reaction to any type of tissue injury. In the blood of healthy horses, SAA concentration is very low, but it increases dramatically with inflammation. Due to the short half-life of SAA, changes in its concentration in blood closely reflect the onset of inflammation and, therefore, measurement of SAA useful in the diagnosis and monitoring of disease and response to treatment. SAA has proven useful for detection of some subclinical pathologies that can disturb training and competing in equine athletes. Increasing availability of diagnostic tests for both laboratory and field use adds to SAA’s applicability as a reliable indicator of horses’ health status.

Equine Fibrinogen

This assay is based on the reaction between fibrinogen antigen and anti-fibrinogen antibody. This reaction forms an insoluble complex producing a turbidity, which is measured spectrophotometrically. The amount ofcomplex formed is directly proportional to the amount of fibrinogen in the sample

Fibrinogen is an acute-phase reactive protein, which increases in response to inflammation and tissue damage. This assay may help with diagnosis and prognosis in cases of internal abscessation, chronic infectious or parasitic disease and exercise induced pulmonary haemorrhage. When run alongside with serum amyloid A this can be very helpful when monitoring response to treatment.

 

GLDH

Glutamate dehydrogenase (GLDH) is a mitochondrial enzyme which is present in many tissues. Significant elevations of the GLDH activity are measured in necrosis of hepatocytes, as in acute toxic liver necrosis and in hypoxic liver diseases. The measurement of GLDH is used to evaluate the extent of parenchymal liver damage and, in conjunction with the transaminases ALAT/GPT and ASAT/GOT, in the differential diagnosis of liver disorders. The calculation of the (ALAT+ASAT)/GLDH ratio enables to differentiate between inflammatory liver diseases and liver necrosis due to intoxication or ischemia

 

 

Glutathione Peroxidase (GPx)

Glutathione Peroxidase (GPX) catalyses the oxidation of Glutathione (GSH) by Cumene Hydroperoxide. This method is based on that of Paglia and Valentine. In the presence of Glutathione Reductase (GR) and NADPH, the oxidised Glutathione (GSSG) is immediately converted to the reduced form with a concomitant oxidation of NADPH to NADP+.

GPx displays an inverse correlation with free radicals and consequently oxidative stress. A reduction in GPx activity, can cause antioxidant protection to be impaired, resulting in oxidative damage to the membrane fatty acids and functional proteins, resulting in neurotoxic damage. Decreased GPx activity can result in progression of several health problems, including: cardiovascular disease (CVD), diabetes, atherosclerosis and neurodegenerative disorders.

b-hydroxybutyrate (BHB)

In patients suffering from starvation, acute alcohol abuse, or diabetes mellitus ketosis can result in severe life threatening metabolic acidosis. The presence and degree of ketosis can be determined by measuring blood levels of D-3-Hydroxybutyrate. Ordinarily, D-3-Hydroxybutyrate is the ketoacid present in the greatest amount in serum. It accounts for approximately 75% of ketone bodies which also contain acetoacetate and acetone. During periods of ketosis, D-3-Hydroxybutyrate increases even more than the other two ketoacids, acetoacetate and acetone, and has been shown to be a better index of ketoacidosis including the detection of subclinical ketosis. In diabetes, the measurement of D-3-Hydroxybutyrate as well as the blood glucose is needed for the assessment of the severity of diabetic coma and is essential for the exclusion of hyperosmolar non-ketotic diabetic coma. Moreover, the insulin requirements are often based on the extent of the existing hyperketonemia shown by the blood levels of D-3-Hydroxybutyrate and is therefore extremely important.

 

NEFA

tissues. The amount at NEFA in serum depends on a balance between intake in liver and peripheral tissues, and the release from adipose tissues. Amount of NEFA decreases by physical exercise, increases by starvation, cold, fear or smoking. And then increase or decrease of NEFA is observed in diabetes, hepatic diseases, or endocrine diseases. NEFA had been assayed by organic solvent extraction method, which was complicated to operate. Enzymatic method using Acyl-CoA oxidase (ACOD) has become widespread due to excellent specificity and concise procedure. This assay is based on the enzymatic method using 3-Methyl-NEthyl- N-(β-Hydroxyethyl)-Aniline (MEHA) as a violet colour agent. It gives reliable results without interference from ascorbic acid and bilirubin.

Zinc (Zn)

Zinc forms with 2-(5-Brom-2-pyridylazo)-5-(N-propyl-N-sulfopropylamino)-phenol, a red chelate complex. The increase of absorbance is proportional to the concentration of total zinc. ZN has a key role in growth, reproduction, sexual maturity, and the immune system. ZN is vitally important in the functionality of >300 enzymes utilised in the stabilisation of DNA and gene expression. Zinc deficiency has been identified as a malnutrition issue worldwide. ZN deficiency is more prevalent in areas of low animal consumption and high cereal consumption. During growth periods, ZN deficiency causes growth failure. The organs most affected by ZN deficiency include central nervous system, epidermal, gastrointestinal, immune, reproductive and skeletal systems ².

Copper (Cu)

Copper forms with 4-(3, 5-dibromo-2pyridylazo)-N-ethyl-N-sulfopropylanine a chelate complex. The increase of absorbance of this complex can be measured and is proportional to the concentration of total copper in the sample. Copper is an essential trace mineral, naturally available in some foods and as dietary supplements.

 

Thyroxine (T4)

The Glenbio Thyroxine Assay is a homogeneous enzyme immunoassay using ready-to-use liquid reagents. Thyroxine (T4) is synthesized within the follicles of  the thyroid gland and released into the blood circulation through a complex feedback system. The thyroid gland is regulated by the thyroid stimulating hormone (TSH) which is produced and secreted by the pituitary gland.

The production and secretion of TSH by the pituitary is through the stimulation by the thyroid releasing hormone (TRH) which is released by the hypothalamus. Most thyroxine in blood circulation is predominantly bound to thyroxine binding globulin (TBG) and to a lesser extent to thyroxine binding albumin and pre-albumin. Only less than 1% of thyroxine remains unbound as free T4 in blood. Elevated total thyroxine levels have been associated with hyperthyroidism, a condition with an excess amount of circulating thyroid hormone and decreased total thyroxine levels have been associated with hypothyroidism, a condition with insufficient levels of thyroxine concentration.

The Glenbio Thyroxine assay uses 8-anilino-1-naphthalene sulfonic acid (ANS) to dissociate thyroxine from the plasma binding proteins. The dissociated thyroxine in the sample can compete with an enzyme glucose-6-phosphate dehydrogenase (G6PDH) labelled thyroxine for a fixed amount of anti-thyroxine specific antibody binding sites in the solution. In the absence of thyroxine from the sample, the G6PDH labelled thyroxine is bound by the specific antibody and the enzyme activity is inhibited. This phenomenon creates a relationship between thyroxine concentration in the sample and the enzyme activity.

 

Canine CRP

C-reactive protein is an acute phase protein produced in the liver hepatocytes as response to inflammatory stimuli. Increased production of CRP can be detected 4-6 hours after induction with a peak concentration within 48 hours. The canine serum or plasma sample is mixed with canine CRP immunoparticles. Canine CRP from the sample and the immunoparticles’ anti-canine CRP aggregate. The complex particles created absorb light, and turbidimetric measurements of absorption are related to canine CRP concentration via interpolation on an established standard calibration curve.

 

Phenobarbital

Phenobarbital has been widely prescribed for the treatment of epilepsy, particularly for controlling focal motor or sensory and grand mal seizures. Phenobarbital in circulation is approximately 40% to 50% bound to plasma proteins with relatively low association constants. The major metabolic pathway of phenobarbital is hydroxylation of the phenyl ring to p-hydroxyphenobarbital, an agent devoid of hypnotic activity, which is then excreted in the urine in equal amounts of the free form and the form conjugated with glucuronic acid. Phenobarbital concentrations of 15-40 μg/mL in serum are normally considered to be within the therapeutic range for maximum seizure control. The need for monitoring phenobarbital concentrations is due to the narrow therapeutic index and the wide variability in individual rates of drug absorption, metabolism, and clearance. Toxicity of phenobarbital therapy includes sedation, nystagmus, ataxia, paradoxical excitement, blood dyscrasia (including coagulation defects in neonates of mothers given the drug during pregnancy), non-specific hepatic changes, rash (including severe exfoliative forms), osteomalacia, the shoulder-hand syndrome and coma. In combination with other clinical information, monitoring serum or plasma phenobarbital levels will provide physicians with an essential tool to aid in adjusting dosage and achieving optimal therapeutic effect, while avoiding both subtherapeutic and harmful toxic drug levels.

 

Gentamicin 

Gentamicin is an aminoglycoside antibiotic used in the treatment of infections caused by E. coli, Klebsiella, Enterobacter, Proteus mirabilis, Pseudomonas aeruginosa, Serratia, Staphylococcus aureus, Staphylococcus epidermidis and other microorganisms. Gentamicin’s toxic effect is produced by interfering with ribosomal protein synthesis. Gentamicin undergoes very little, if any, metabolization and is, therefore, eliminated as the parent drug by glomerular filtration. The therapeutic range should be measured at peak as well as trough concentrations. Peak serum or plasma concentrations of gentamicin are suggested to ensure that adequate antimicrobial activity is obtained. Trough gentamicin concentrations usually ensure that drug elimination is adequate and the drug concentration is above minimum inhibitory concentration. Serum or plasma gentamicin concentration is impacted by mode of administration, the volume of extracellular fluid, the duration of the treatment and physiological changes during the illness and therapy. Therefore, monitoring of peak and trough gentamicin serum or plasma levels is critical in the prevention of these serious complications with the adjustment of dosage administration as indicated.

The assay is based on the bacterial enzyme b-galactosidase, which has been genetically engineered into two inactive fragments i.e., enzyme acceptor (EA) and enzyme donor (ED). These fragments spontaneously
reassociate to form fully active enzyme that, in the assay format, cleaves a substrate, generating a color change that can be measured spectrophotometrically.
In the assay, analyte in the sample competes with analyte conjugated to one inactive fragment of b-galactosidase for antibody binding site. If analyte is present in the sample, it binds to antibody, leaving the inactive enzyme fragments free to form active enzyme. If analyte is not present in the sample, antibody binds to analyte conjugated on the inactive fragment, inhibiting the reassociation of inactive b-galactosidase fragments, and no active enzyme is formed. The amount of active enzyme formed and resultant absorbance change are directly proportional to the amount of drug present in the sample

Quinidine

The Glenbio Quinidine assay is a homogeneous particle-enhanced turbidimetric immunoassay. The assay is based on competition between drug in the sample and drug coated onto a microparticle for antibody binding sites of the quinidine antibody reagent. The quinidine-coated microparticle reagent is rapidly agglutinated in the presence of the anti-quinidine antibody reagent and in the absence of any competing drug in the sample. The rate of absorbance change is measured photometrically. When a sample containing quinidine is added, the agglutination reaction is partially inhibited, slowing down the rate of absorbance change. A concentration dependent classic agglutination inhibition curve can be obtained with maximum rate of agglutination at the lowest quinidine concentration and the lowest agglutination rate at the highest quinidine concentration.

 

Glenbio Veterinary Packages