PROTEINS AND ENZYME ACTIVITIES IN THE BLOOD OF COWS IN LATE PREGNANCY AND IN THEIR FOETUSES

Bouda J., P. Jagos: Proteins and Enzyme Activities in the Blood of Cows in Late Pregnancy and in Their Foetuses. Acta vet. Brno, 48, 1979: 15-18. Experiments involving 20 cows in late pregnancy and their foetuses were conducted to study the total serum proteins and their fractions. Futther activities of GOT, AP, LDH and gamma-GT were measured in maternal and foetal plasma. The total serum protein of the foetuses amounted 42 gil and was significantly lower (P < 0.01) than that of their mothers. These low total protein levels in foetal serum were connected with low y-globulin levels amounting 1.1 gil as compared to 22.6 gil found in maternal serum. In the foetal sera higher levels of albumin and IX globulins were found. Immunoglobulins measured by the turbidimetric method in the foetal and maternal sera correlated with their y-globulin content. Activity of the maternal plasma GOT surpassed that of the foetal enzyme three times. The activities of maternal plasma LDH and y-GT were higher (P < 0.01) than those of the foetal plasma enzymes. On the other hand, significantly higher (P < 0.01) AP activity was found in the foetal plasma as compared to the maternal plasma enzyme activity. Blood, plasma, serum, albumin, CX-, {J-, y-globulin, Ig, GOT, alkaline phosphatase, LDH, y-glutamyltranspeptidase. Numerous experimental data have shown that the blood serum of newborn calves contains almost no y-globulin. As early as 1892 Ehrlich proved that the maternal antibodies are transferred to the newborn calf by colostrum. The postnatal development of animals with the syndesmochorial type of placenta is dependent upon the physiological and immunological condition of their mothers (Pi'ibyl 1963; Fey 1972; Logan 1977; Hajdu et al. 1977). The total protein amount and protein fractions in the blood serum of foetuses and newborn calves prior to feeding colostrum are substantially lower than those found in their mothers (Baetz et al. 1971; Boguth 1953; Piskac 1961; Barta '1962; Hojovcova 1965). Investigations into the foetal plasma enzyme activities indicated the GOT activity to be by about 50 % lower as compared to data for the adult cattle (Baetz et al. 1971). Similarly, lower GOT activity was found in calves prior to feeding colostrum (Maderova et al. 1960; Griin and Klotzer 1973). On the other hand, activity of the alkaline phosphatase in the foetal plasma was found to increase with age and to surpass remarkably the values found in the dams (Baetz et al. 1971). From the diagnostic point of view great attention has been recently given to y-glutamyl-transpeptidase (y-GT). No data concerning this enzyme in calf foetuses are as yet available. The aim of the present experiment was to study the relationships between the maternal and foetal serum protein levels, serum protein fractions, and plasma enzyme activities in cattle. Materials and Methods For experiments, 20 healthy cows of the Czech spotted breed in late pregnancy and their 8-9-month-old foetuses were employed. The average body mass of the foetuses was 32.1 kg ranging from 24.5 to 43.0 kg. The foetuses were extracted by Caesarean section at the Depattment of

Numerous experimental data have shown that the blood serum of newborn calves contains almost no y-globulin.As early as 1892 Ehrlich proved that the maternal antibodies are transferred to the newborn calf by colostrum.The postnatal development of animals with the syndesmochorial type of placenta is dependent upon the physiological and immunological condition of their mothers (Pi'ibyl 1963;Fey 1972;Logan 1977;Hajdu et al. 1977).The total protein amount and protein fractions in the blood serum of foetuses and newborn calves prior to feeding colostrum are substantially lower than those found in their mothers (Baetz et al. 1971;Boguth 1953;Piskac 1961;Barta '1962;Hojovcova 1965).
Investigations into the foetal plasma enzyme activities indicated the GOT activity to be by about 50 % lower as compared to data for the adult cattle (Baetz et al. 1971).Similarly, lower GOT activity was found in calves prior to feeding colostrum (Maderova et al. 1960;Griin and Klotzer 1973).On the other hand, activity of the alkaline phosphatase in the foetal plasma was found to increase with age and to surpass remarkably the values found in the dams (Baetz et al. 1971).
From the diagnostic point of view great attention has been recently given to y-glutamyl-transpeptidase (y-GT).No data concerning this enzyme in calf foetuses are as yet available.
The aim of the present experiment was to study the relationships between the maternal and foetal serum protein levels, serum protein fractions, and plasma enzyme activities in cattle.

Materials and Methods
For experiments, 20 healthy cows of the Czech spotted breed in late pregnancy and their 8-9--month-old foetuses were employed.The average body mass of the foetuses was 32.1 kg ranging from 24.5 to 43.0 kg.The foetuses were extracted by Caesarean section at the Depattment of Reproduction and Surgery of Farm Animals in order to obtain the foetal sera.Blood samples were collected from v. jugularis of the dams and from a. carotis of the foetuses.
The total protein levels were measured in maternal and foetal serum fotometrically using the Bio-Test (Biuret method) by Lachema, Bmo.Electrophoretic separations of serum proteins on acetate foils using the Microphor Boskamp apparatus was conducted for 20 minutes.The protein fractions were evaluated using the Densiscan by Kipp and Zonen.
Serum immunoglobulins were determined by the turbidimetric method using the zinc-sulphate agent according to McEvan et al. (1970).
Activities of plasma GOT, AP ,,-GT were determined fotometrically using the Bio-Tests by Lachema, Bmo.The LDH activity was measured using the kit Sevac-LDH by Imuna, SariSske Michal'any.
The activities of plasma GOT, AP, LDH and je-GT are given in Table 2.The foetal GOT activity was about 3 times lower than that of the maternal enzyme.The foetal LDH and y-GT activities were about half the values found in maternal plasma.On the other hand, much higher AP activity was found in plasma of the foetuses.All the above-mentioned differences were significant (P < 0,01).

Discussion
Our study revealed remarkable differences in the amount of serum proteins and their fractions of pregnant cows and their foetuses.These data are in good agreement with those of Baetz et a!. (1971).These authors found the total protein amount of the foetal serum to increase from 2.6 g/l00 ml in 5-month-old foetuses to 4.0 gjlOO ml in the 8-month-old ones.The total protein concentration in serum of foetuses in our experiment did not differ from its values found in the newborn calves prior to the intake of colostrUm (J agos et al. 1977, 1978).
The total protein in the serum of foetuses consisted of 55 % albumin, 33 % ex-globulin and of 3 % y-globulin.The greatest differences between the maternal and foetal sera were noted in the content of ex-and y-globulin.Immunoglobulins correlated with the y-globulin content.
Earlier workers reported on the absence of globulin in the serum of calves prior to feeding colostrUm.Nevertheless, in the present work y-globulins were found in the foetal serum ranging from ° to 2.9 gil (average 1.1 gil).This value is lower than that reported by Baetz et al. (1971).At present, it is thought that some antibody synthesis occurs also in foetuses, probably after transplacental transfer of antigens.
In our study only cows showing no clinical signs of illness were included.This was important for the determination of enzyme activities in pregnant cows and their foetuses.The GOT activity found in the foetuses was not only significantly lower than in their mothers but also lower than in calves after birth (J agos et al. 1977, 1978).The GOT activity in the maternal plasma oscillated within the reference values (J agos et al. 1975).Similar relationship of the maternal and foetal GOT found also Baetz et a!. (1971) although they noted somewhat higher activities of this enzyme for the foetuses.
In foetuses the LDH and y-GT activities were about half the values found in their mothers.The maternal LDH activity was within the reference values (J agos et al. 1975) whereas the y-GT was found to be slightly elevated.The finding of more than three times higher AP activity in fOC?tuses is not surprising as this phenomenon in young animals (Haschen 1970;Slesinger 1970) is connected with growth of the bones.Bilkoviny a aktivita enzymit v krvi vysokobrezich krav a jejich fetit V krevnim seru 20 vysokobfezich krav a jejich fem byla stanovena celkova bllkovina a jeji frakce.Z enzymii.v krevni plazme byla stanovena aktivita GOT, AP, LDH, gama-GT.

Table 2
Enzyme activities in the plasma of 20 cows and their foetuses