*5.2.2. Changes in the globulin fractions*

of the intestinal absorption of proteins (particularly immunoglobulins) from colostrum. On the other hand, the concentrations of albumin decrease 1 day after colostrum intake, with a subsequent gradual increase from day 2 till the end of the first month of life. At birth, calve's

observed with a subsequent gradual decrease. The delivery is surely a stressful situation for the offspring and it could typically be expressed by higher concentrations of acute-phase proteins at birth, which migrate into this fraction [148]. The acute-phase response may be then substituted by the following increase of the IgG concentrations from the colostrum. Acutephase proteins are produced mainly by the liver, which is less mature in newborn than in young or adult animals. Thus, the most of the acute-phase proteins have lower concentrations at birth than in the next days [231]. Similarly, large amounts of α-globulins were observed in

Pregnancy and lactation are further factors that may influence the concentrations of albumin and globulin fractions. Variations in the serum protein profile were found in ewes during the pregnancy and lactation, as well as in periparturient goats [233–235]. Changes in the concentrations of protein fractions during the last phase of pregnancy and early *post-partum* were recorded also in dairy cows [236]. Lower concentrations of total serum proteins were found by Grünberg et al. [237] in cows around parturition than outside the parturient period and in the following stages of lactation. These changes may be associated with the transfer of immunoglobulins from the bloodstream to the mammary gland for the synthesis of colostrum [238]. The results of Piccione et al. [235, 239] showed increasing values of α-globulins in dairy cows and ewes *post-partum*, which were probably related to the higher concentrations of the acute-phase proteins in response to the processes occurring around the time of parturition.

The concentrations of serum proteins may be influenced also by hormonal changes and stress. Stress may cause a decrease of serum protein and albumin concentrations, but often may

A wide variety of diseases can cause changes in the serum protein pattern [240]. The serum protein electrophoresis is a very important technique for the evaluation of these abnormalities and the nature of the hyperproteinemia or hyperglobulinemia [241]. The protein electrophoresis may be very useful when routine investigations are not effective for making medical

The decrease of the concentrations of albumin is one of the most frequently occurring types of dysproteinemias. Hypoalbuminemia can be caused by decreased production due to liver diseases such as chronic hepatitis, cirrhosis, or liver failure [243]. Hypoalbuminemia may be

decisions, providing the basis for further specific laboratory analyses [22, 242].




alpha<sup>1</sup>

In the absolute concentrations of α<sup>1</sup>

122 Ruminants - The Husbandry, Economic and Health Aspects

lambs during the first month of life [232].

be accompanied by an increase of the α<sup>2</sup>

*5.2.1. Changes in the albumin fraction*

**5.2. Pathological serum protein pattern: dysproteinemias**

response [7].

Increases in the globulin fractions may be frequently seen on serum protein electrophoretograms. Since many acute-phase proteins belong to the alpha-globulin fraction, increase in the α<sup>1</sup> - and α<sup>2</sup> -zones may be typical for many acute, as well as chronic inflammatory diseases caused by the activation of the host inflammatory responses [71]. Increased α-globulins (predominantly α<sup>1</sup> -globulins) were found in sheep naturally infected with *Babesia ovis*, as well as in calves affected by respiratory diseases [251, 252]. The α<sup>2</sup> -globulin fraction typically increases in patients with nephrotic syndrome as a result of the increased synthesis of α2 -macroglobulin that migrates in this fraction. Because of its size, the α<sup>2</sup> -macroglobulin is unable to pass through glomeruli and therefore it remains in the bloodstream [253]. Decreases in the α<sup>1</sup> -globulin fraction may be detected in the α<sup>1</sup> -antitrypsin deficiency, a rare genetic disorder in humans and even more rare in animals, but in ruminants, it was not yet detected [254]. Similarly, the α<sup>2</sup> -globulin zone may be typically decreased in hemolytic anemia, when haptoglobin from this fraction binds with the free hemoglobin released from the destroyed red blood cells, forming haptoglobin-hemoglobin complexes that are rapidly removed by phagocytes [76]. On the other hand, the inflammatory conditions that develop in association with hemolytic anemia leads to an increase of haptoglobin concentration that may induce an increase of α<sup>2</sup> -globulins [255].

Some acute-phase proteins migrate into the β-region. Thus, several inflammatory diseases and infections may be accompanied also by increases in the β-fraction as a result of the elevated production of these proteins. Kaneko [22] stated that increases solely in the β-globulin fraction are not frequent and may be typical for active hepatitis. Chronic persistent liver disease, liver cirrhosis, as well as nephrotic syndrome may be associated with elevations in the β-region due to the increase of the concentrations of β<sup>2</sup> -microglobulin in these conditions [256]. High β-globulin concentrations may be associated also with hypercholesterolemia, which is caused by increased concentrations of β-lipoproteins in this fraction [257]. Furthermore, increased β-globulins are typical for iron deficiency anemia associated with higher values of transferrin [258]. The increase of β-globulins in hemolytic anemia may depend on the presence of free hemoglobin that typically migrates in this region. On the other hand, malnutrition is often accompanied with decreased concentrations of β-globulins.

after the intake of colostrum, and the absorption continues for up to 24–36 hours after birth, after which gut permeability ceases [268, 269]. Hypogammaglobulinemia may be commonly seen also in patients with recurrent infections or in cases of immune deficiency, including pri-

The Use of Serum Proteins in the Laboratory Diagnosis of Health Disorders in Ruminants

http://dx.doi.org/10.5772/intechopen.72154

125

The aforementioned shifts in the concentrations of albumin and globulins lead also to changes in the albumin: globulin ratio (A/G). The normal A/G ratio is in the range of 0.6–0.9 in cows, but the relative concentrations of albumin and globulins may be altered in many disease conditions, which results in changes in their proportion [22]. Decreased A/G ratio may be associated with the overproduction of globulins, decreased synthesis of albumin, or with losses of albumin from the circulation. On the other hand, higher A/G ratio is usually caused by the underproduction of globulins. Thus, the interpretation of A/G ratio is very important itself providing information about the changes in pattern of serum proteins, and could help in the

The analysis of serum proteins and their electrophoretic separations have been extensively used in human medicine for many years. Serum protein electrophoresis has been studied intensively also in small animal and equine medicine, especially to support a clinical diagnosis of diseases characterized by dysproteinemia (leishmaniasis, ehrlichiosis, feline infectious peritonitis), or to identify the presence of inflammation with increased α-globulins [76]. In

The diagnostic significance of protein electrophoresis in cows with traumatic pericarditis was evaluated by Yoshida [270]. In the affected cows, slight hypoproteinemia, moderate hypoalbuminemia, and a slight increase of the α- and β-globulin concentrations were observed. In cows with purulent pericarditis, they found a tendency of hypergammaglobulinemia, while fibrinous or sero-fibrinous pericarditis was associated with a large indentation between the β- and γ-fractions. The changes in the electrophoretic pattern of serum proteins and immunoglobulin concentrations were studied also in cows with lymphoma [271]. Moderately increased con-

nificantly decreased due to the lower concentration of immunoglobulins. Recently, Tóthová et al. [252] evaluated the effect of chronic bronchopneumonia on the serum protein pattern in

the affected animals compared with healthy ones. Alterations in the electrophoretic pattern of serum proteins were found also in dairy cows with inflammatory diseases [263]. In this study, *post-partum* metritis was associated with significantly lower concentrations of albumin and

γ-globulins were found. Furthermore, the serum protein electrophoretic pattern of more than








bovine clinical practice, serum protein electrophoresis is a rarely used diagnostic tool.


calves. These authors found significantly higher concentrations of α<sup>1</sup>

significantly lower concentrations of albumin and higher values of α<sup>1</sup>

mary immunodeficiency disorders [1].

**practice**

centrations of α<sup>2</sup>

higher values of α<sup>1</sup>

mastitis showed higher β<sup>1</sup>

classification and identification of dysproteinemias [105].

**6. The use of serum protein electrophoresis in bovine clinical** 

In some conditions, the increase in the β<sup>2</sup> - and γ-globulin fractions may result in a beta-gamma fusion. This phenomenon is called β-γ bridging and is characterized with no clear demarcation between these two fractions. It is caused by an increase of the concentrations of IgM or IgA, which may migrate in the region between the beta and gamma zones [259]. According to some authors, the pattern of β-γ bridging is pathognomonic for chronic liver diseases or hepatic cirrhosis [260]. However, Camus et al. [261] stated that β-γ bridging does not have a strong predictive value for hepatic diseases in some animal species, including dogs, cats, or horses, and may be frequently found in association with infectious diseases, including leishmaniasis or ehrlichiosis [262]. Tóthová et al. [263] observed also a β-γ fusion in cows with severe hoof diseases. Other possible source of the β-γ bridge is the use of plasma instead of serum, caused by the migration of fibrinogen between the β and γ regions [16].

Increases of the γ-globulin fraction (the so-called gammopathies) belong to the frequent serum protein alterations, and are typical for many pathological conditions. Two types of gammopathies were differentiated: monoclonal and polyclonal. Monoclonal gammopathy is characterized by a sharp, homogenous, spike-like peak in the focal region of the γ-globulin zone. This pattern may be caused by the production of excessive amounts of one type of immunoglobulin secreted by a single clone of B lymphocytes, or an immunoglobulin fragment described as paraprotein or M protein [264]. Multiple myeloma is the most common malignant disorder of plasma cells, in which usually IgA and IgG paraproteins can be found [265]. Monoclonal gammopathies in farm animals are not frequent. Some cases were recorded in horses and small animals, which has been associated with plasma cell myeloma, malignant lymphoma, or erythrophagocytic multiple myeloma [264, 266].

Polyclonal gammopathy is associated with the presence of a diffuse hypergammaglobulinemia, in which all immunoglobulin classes may be increased. It is characterized by a diffuse, broad increase in the γ-globulin zone on the electrophoretogram. This swell-like elevation of γ-globulins is mostly caused by inflammatory reactions, and usually indicates a non-malignant condition [71]. The most common causes of polyclonal gammopathies are chronic inflammatory processes (gastrointestinal, respiratory, endocrine, cardiac), severe infections, as well as immune-mediated disorders [76, 267]. The decrease of the concentrations of γ-globulins in the serum is called hypogammaglobulinemia. This pattern is typical for fetal or precolostral sera in some animal species. In calves, precolostral serum normally contains no (agammaglobulinemia) or very low concentrations of γ-globulins, but they start to increase within a few hours after the intake of colostrum, and the absorption continues for up to 24–36 hours after birth, after which gut permeability ceases [268, 269]. Hypogammaglobulinemia may be commonly seen also in patients with recurrent infections or in cases of immune deficiency, including primary immunodeficiency disorders [1].

production of these proteins. Kaneko [22] stated that increases solely in the β-globulin fraction are not frequent and may be typical for active hepatitis. Chronic persistent liver disease, liver cirrhosis, as well as nephrotic syndrome may be associated with elevations in the β-region

β-globulin concentrations may be associated also with hypercholesterolemia, which is caused by increased concentrations of β-lipoproteins in this fraction [257]. Furthermore, increased β-globulins are typical for iron deficiency anemia associated with higher values of transferrin [258]. The increase of β-globulins in hemolytic anemia may depend on the presence of free hemoglobin that typically migrates in this region. On the other hand, malnutrition is often

fusion. This phenomenon is called β-γ bridging and is characterized with no clear demarcation between these two fractions. It is caused by an increase of the concentrations of IgM or IgA, which may migrate in the region between the beta and gamma zones [259]. According to some authors, the pattern of β-γ bridging is pathognomonic for chronic liver diseases or hepatic cirrhosis [260]. However, Camus et al. [261] stated that β-γ bridging does not have a strong predictive value for hepatic diseases in some animal species, including dogs, cats, or horses, and may be frequently found in association with infectious diseases, including leishmaniasis or ehrlichiosis [262]. Tóthová et al. [263] observed also a β-γ fusion in cows with severe hoof diseases. Other possible source of the β-γ bridge is the use of plasma instead of

Increases of the γ-globulin fraction (the so-called gammopathies) belong to the frequent serum protein alterations, and are typical for many pathological conditions. Two types of gammopathies were differentiated: monoclonal and polyclonal. Monoclonal gammopathy is characterized by a sharp, homogenous, spike-like peak in the focal region of the γ-globulin zone. This pattern may be caused by the production of excessive amounts of one type of immunoglobulin secreted by a single clone of B lymphocytes, or an immunoglobulin fragment described as paraprotein or M protein [264]. Multiple myeloma is the most common malignant disorder of plasma cells, in which usually IgA and IgG paraproteins can be found [265]. Monoclonal gammopathies in farm animals are not frequent. Some cases were recorded in horses and small animals, which has been associated with plasma cell myeloma, malignant

Polyclonal gammopathy is associated with the presence of a diffuse hypergammaglobulinemia, in which all immunoglobulin classes may be increased. It is characterized by a diffuse, broad increase in the γ-globulin zone on the electrophoretogram. This swell-like elevation of γ-globulins is mostly caused by inflammatory reactions, and usually indicates a non-malignant condition [71]. The most common causes of polyclonal gammopathies are chronic inflammatory processes (gastrointestinal, respiratory, endocrine, cardiac), severe infections, as well as immune-mediated disorders [76, 267]. The decrease of the concentrations of γ-globulins in the serum is called hypogammaglobulinemia. This pattern is typical for fetal or precolostral sera in some animal species. In calves, precolostral serum normally contains no (agammaglobulinemia) or very low concentrations of γ-globulins, but they start to increase within a few hours

serum, caused by the migration of fibrinogen between the β and γ regions [16].

lymphoma, or erythrophagocytic multiple myeloma [264, 266].



due to the increase of the concentrations of β<sup>2</sup>

124 Ruminants - The Husbandry, Economic and Health Aspects

In some conditions, the increase in the β<sup>2</sup>

accompanied with decreased concentrations of β-globulins.

The aforementioned shifts in the concentrations of albumin and globulins lead also to changes in the albumin: globulin ratio (A/G). The normal A/G ratio is in the range of 0.6–0.9 in cows, but the relative concentrations of albumin and globulins may be altered in many disease conditions, which results in changes in their proportion [22]. Decreased A/G ratio may be associated with the overproduction of globulins, decreased synthesis of albumin, or with losses of albumin from the circulation. On the other hand, higher A/G ratio is usually caused by the underproduction of globulins. Thus, the interpretation of A/G ratio is very important itself providing information about the changes in pattern of serum proteins, and could help in the classification and identification of dysproteinemias [105].
