HEMATOLOGICAL VALUES OF THE BLOOD IN RAMS DURING REARING

Jelinek P., J.IIlek, Ivana Helanova, Z. Frais: Biochemical and Hematological Values in the Blood of Rams during Rearing. Acta vet. Brno, 53, 1984: 143-150. The dynamics of some hematological and biochemical indices was studied in 45 rams reared in a central stock rearing house in the breeding season of 1982/1983. The results showed that the observed biochemical and hematological values correspond with the physiological standard. With advancing age a decrease was observed of the total count of erythrocytes, hemoglobin, hematocrit, inorganic phosphorus and glucose. The nutritional level affected the content of urea and phosphorus in the blood plasma. A negative, highly significant correlation was proved between the age and the glucose level, and a positive, highly significant relationship between the total protein content and amount of wool in the grease and technically clean wool. The data obtained in this study may be employed for evaluation of the health ~tatus and nutrition of rams during rearing. The data may also serve as reference values for Merino ram-Iambs in the respective age categories. Rams, blood picture, nutrition, age, blood plasma, biochemistry. The presumption for a full development of genetic potential of all the productive characters of sheep are suitable environmental conditions during rearing. In order to evaluate their effect upon the developing organisms, however, it is necessary to know as many indices as possible, as they reflect these effects and, signalize the level of nutrient supply, mineral substances, vitamins; at the same time, they manifest the functional condition of the animal. From this aspect most important is knowledge about the basic hematological and biochemical blood indices which holds good especially in the young, developing animals. The importance of these laboratory analyses increases with the loading ofthe organism, may it be the effect of inconventional technology, degree of exploitation, method of nutrition, use of new genotypes, or when evaluating various experimental measures. Many studies have been written dealing with hematological values and metabolic profile of sheep blood (Soliman et al. 1975; Thomas and Axford 1968; Holub et aI. 1969; Sova and Medficky 1972; Hofirek 1978; Jelinek et aI. 1982, 1983; Vrzgula et al. 1965, 1973, 1982; Underwood 1971; Hennig 1972; BoISedanov 1973; Ried et al. 1974; Vrzgula and Skalka 1977; Jagos et. aI. 1980a). Only few studies were aimed at determination of the basic hematological and biochemical data with respect to age, sex, season, breed, etc. Therefore in the present study the basic hematological parameters and indices of the metabolic profile of blood plasma in Merino rams were studied. Suitability of these indices for evaluation of their nutritional status and metabolic disorders was verified as well.

The presumption for a full development of genetic potential of all the productive characters of sheep are suitable environmental conditions during rearing.In order to evaluate their effect upon the developing organisms, however, it is necessary to know as many indices as possible, as they reflect these effects and, signalize the level of nutrient supply, mineral substances, vitamins; at the same time, they manifest the functional condition of the animal.From this aspect most important is knowledge about the basic hematological and biochemical blood indices which holds good especially in the young, developing animals.The importance of these laboratory analyses increases with the loading ofthe organism, may it be the effect of inconventional technology, degree of exploitation, method of nutrition, use of new genotypes, or when evaluating various experimental measures.Many studies have been written dealing with hematological values and metabolic profile of sheep blood (Soliman et al. 1975;Thomas and Axford 1968;Holub et aI. 1969;Sova and Medficky 1972;Hofirek 1978;Jelinek et aI. 1982Jelinek et aI. , 1983;;Vrzgula et al. 1965Vrzgula et al. , 1973Vrzgula et al. , 1982;;Underwood 1971;Hennig 1972;BoISedanov 1973;Ried et al. 1974;Vrzgula and Skalka 1977;Jagos et. aI. 1980a).Only few studies were aimed at determination of the basic hematological and biochemical data with respect to age, sex, season, breed, etc.
Therefore in the present study the basic hematological parameters and indices of the metabolic profile of blood plasma in Merino rams were studied.Suitability of these indices for evaluation of their nutritional status and metabolic disorders was verified as well.

Materials and Methods
Mean hematological and biochemical values were estimated in 45 randomly selected, clinically healthy rams of Merino breed reared in the stock rearing houses of the Regional Breeding Enterprise in Ceske Budejovice-Zavraty.The animals were deep-litter housed in groups of 10 animals and fed ad libitum with a complete granulated mixture which was supplemented with hay and grazing after the end of the testing period.During rearing the ram-lambs were wormed three times (May 19, 1982, October 13, 1982and January 19, 1983).
Blood was examined in 4 time periods with regard to selective interventions, i. e. prior to the testing period on March 29, 1982 (average age 90 days and live weight 24.0 kg), after the end of the testing period on June 4, 1982 (average live weight 42.3 kg), on November 2, 1982 (average live weight 58.8 kg), the last sampling was done on January 18, 1983 (average live weight 74.8 kg).
Blood was taken from the v. jugularis into heparinized test tubes at the same time of the day and from the same animals, the number of which decreased in the course of rearing due to gradual selection.Blood plasma for the estimation of biochemical values was obtained up to 30 minutes after blood collection.From these blood samples the following hematological values were estimated using the classical method: erythrocytes, hemoglobin, hematocrit value, mean corpuscular hemoglobin concentration (MCHC), mean corpuscular hemoglobin (MCH), mean corpuscular value (MCV), leukocytes and their differential count.The total protein level was estimated using the biuret reaction on an Eppendorf photometric line, the content of sodium potassium, calcium, magnesium, copper, and zinc using the AAS method on the Atomspek apparatus by Hilger.Inorganic phosphorus, glucose and urea in the plasma were determined photometrically using the Lachema Bio-Test sets.
Wool production and live weight of the selected animals were investigated for calculations of some correlation relationships among selected indices of the internal environment.
The numbers of leukocytes varied and their average values ranged from 5.52 Gil to 7.19 Gil, what is somewhat lower as compared with the total number of white blood cells as described by Redda and Hathout (1957), Sova and Medficky (1972), Jelinek et al. (in print)  The average values of the most numerous part of the white cell blood constituent, the lymphocytes, ranged between 61.15 % and 75.05 % with a variability of V = 7.29-15.61%.As far as the other agranulocytic type, the monocyte is concerned, the ranges found in the individual periods of rearing in the blood of the ram-lambs, as well as the proportion of lymphocytes, correspond with the values given by the afore mentioned authors.The level of total proteins in the blood plasma ranged from 56.48 to 62.10 gil.These values correspond with the results of J agos et al. (1980) who determined that the range of total proteins in lambs was between 57.3 and 67.9 gil.However, these findings are lower as compared with the authors' previous investigations in intensively fattened ram-lambs where the average concentration ranged from 63.0 to 67.03 gil (J elinek et al. 1983).Further investigations showed that rams with a higher level of total proteins during rearing had a higher clip of wool in the grease which also the value of the coefficient of correlation confirms, i. e. r = 0.412++ for wool in the grease and r = 0.439++ for technically clean wool.
No significant correlations were noted between the live weight andlor age and concentration of total protein.
The urea content during rearing showed a decreasing tendency, i. e. the average value of 7.56 mmol/l at the end of the testing period decreased to 4.40 mmol/l in the last age category.Between the individual time periods there was a statistically significant to highly significant difference.The increased concentration of urea in the blood plasma signalizes a different level of nitrogen uptake from the feed ration.Whereas in the testing period the complete granulated mixture contained 16.5 % of N substances, in the following period it was 12.1 %.The dynamics of urea content in the blood of sheep can be used for the estimation of the level of nitrogenous nutrition both in cattle and pigs (Vrzgula et al. 1982).
With the increasing age of the rams, also the glucose content decreased and between these two data (age and glucose concentration) a negative, highly significant relationship was calculated (r = -0.653++).The decrease of plasma glucose concentration during ontogenesis is connected with the development of the forestomachs and with the increasing role of volatile fatty acids in covering the energy demands of ruminants with these acids (Bartos 1974).No significant correlation (r = 0.097) was found between the level of total proteins and glucose content.The concentrations estimated in the reared rams are in relation with data of Vrzgula et al. (1973Vrzgula et al. ( , 1982)), Riepe (1975), Rofirek (1978), Jelinek et al (1983).
The dynamics of sodium and potassium concentrations in the blood plasma was relatively low.Nor was any seasonal dependence observed, even though there was a somewhat more expressive decrease of potassium in the period of winter housing.In animals and in man, sodium is very sensitively regulated and its level in the blood plasma changes only a little, especially when salt is provided ad libitum.The present findings are in accordance with those of Vrzgula et al. (1973Vrzgula et al. ( , 1982)), Jagos et al. (1980a), Jelinek et al. (1983).
The content of calcium was relatively constant (2.95 to 3.07 mmol/l), proved also in the lower variability level.
The concentration of magnesium, with average values ranging from 0.87 to 0.93 mmol/l, can be characterized in the same way.The ranges of calcium and magnesium contents were within the limits considered to be referential in sheep.Riede et al. (1974) observed a substantial decrease in the magnesium content in blood plasma of sheep at the beginning of the grazing period; however, they did not observe any symptoms of tetany.Neither did they find any effect of an excessive uptake of nitrogen in the feed ration of sheep on the magnesium level; this is an important difference as compared with cattle, because, in the conditions of Czechoslovakia, the increased content of SNL in the feed ration is the main etiological factor of hypomagnesemia in cattle (J agos 1975).Gardner (1973) reported that sheep are more resistant to hypomagnesemic tetany than cattle.
The content of inorganic phosphorus in the blood plasma of reared rams decreased from the initial average value of 2.92 to 2.59 mmol/l in auction rams.This tendency is in accordance with the data of J agos et al. (1980b) who proved a similar dynamics of phosphorus content in calves and young cattle.The increased content of phosphorus influenced the ratio between calcium and phosphorus as well.The content of phosphorus recorded is also due to its increased amount in the feed ration, containing a high proportion of concentrated foods.No effect of the season on the content of calcium and inorganic phosphorus in the blood plasma of rams was proved, in contradistinction to the findings of Bolshedanov (1973) and Lomakina (1974).
The fluctuation of the amount of zinc during rearing was higher but did not exceed the limits of reference values given by Jagos et al. (1980a) for lambs and sheep.
The average values of the copper content in blood plasma ranged from 14.54 (157 days of age) to 17.45,umol/1 (90 days of age) and correspond with findings of Jelinek et al. (1983) intensively fattened ram-lambs of the Merino breed (14.82 to 16.89 ,umol/l).The values of plasma copper found by J agos et al. (1980a) are somewhat higher (21.86 ± 5.68 ,umol/l).The contents of zinc and copper very well reflect the level of their uptake in the feed ration.In the present investigations it means that the feed ration contained an optimum concentration of zinc and copper.It happens very often in practice that the feed rations of fattened lambs have an increased content of copper and could thus cause intoxication by this microelement.Benuska (1977) drew attention to the problem of copper intoxication and he diagnosed massive chronical intoxication characterized by hemolysis and hepatopathy.Under the conditions of Czechoslovakia, deficiency of copper and zinc is not common, unlike some other countries (Underwood 1971).

Table 1
Total mathematical-statistical characteristics of hematological and biochemical indices at the age of 90 days (before the beginning of the testing period).Til in 90-day-old ram-lambs.Hemoglobin in this age span ranged from 102.7 gil (the last age group) to 117.7 gil.The average hematocrit value in ram-lambs during rearing ranged from 0.321/1 to 0.361/1 of blood.The variability within the groups determined by the coefficient of variation showed a low level of variability.Chyla et al.
Redda and Hathout (1957from this aspect, it is pos), Hofirek (1978)se, to consider a certain stability of average values which characterizes the total good health condition of the animals investigated.On the other hand, however, the proportion of eosinophile granulocytes had an increasing tendency during rearing with a high variability within the groups.The range of the mean differential number of eosinophile granulocytes -from 0.55 % to 6.25 %given in the tables corresponds with the data ofRedda and Hathout (1957), Sova  and Medficky (1972), Hofirek (1978),Jelinek et al. (in print).