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The haematological and serum biochemical values of 100 Muturu cattle and 100 Bunaji cattle were studied in two local government areas of Benue State, Nigeria. Haematocrit, red blood cell count, haemoglobin, total white blood cell count, lymphocyte and monocyte counts were significantly higher in Muturu cattle than the Bunaji cattle. However, there were no significant differences in the mean corpuscular volume, mean corpuscular haemoglobin, neutrophil, eosinophil, and basophil counts, albumin, urea, alanine aminotransferase and alkaline phosphatase in the two breeds of cattle. Lower values of mean corpuscular haemoglobin concentration and platelet counts were observed in the Muturu cattle. Similarly, total protein and globulin values were significantly lower in Bunaji than Muturu cattle while the converse is the case with aspartate aminotransferase. The haematological parameters of the two breeds were within the recognized reference intervals for cattle. This study reports for the first time the haematological and some biochemical parameters for Muturu cattle in Benue State.

A comparative cross sectional study was carried out between September and November 2014 to determine the haematocrit values obtained using automated haematology analyser and the microhaematocrit (manual) methods. A total of 197 cattle were sampled. Three (3) ml of blood was obtained from each animal into an EDTA sample bottle for analysis using both methods. The haematocrit data generated was statistically analysed by student's t-test and linear regression. The result showed a strong positive correlation (r=0.946) between the automated haematocrit and microhaematocrit values. The haematocrit values obtained by the automated haematology analyser were significantly higher than the haematocrit values obtained by microhaematocrit method (p=0.0051). The strong positive correlation probably implies that results obtained from both methods are comparable and reliable. A correction factor of the haematocrit value obtained by manual method can be obtained from the regression equation y = 1.043 x + 0.5892 . This may be used to extrapolate the corrected haematocrit value for clinical and research purposes. Keywords: Cattle, Correlation, Haematocrit, Haematology analyser, Microhaematocrit

Alteration of serum electrolytes (Na+, K+, Cl-, and HCO3-) was studied in Zebu cattle experimentally infected with 11.0×106 Trypanosoma vivax. Another group of similarly infected cattle was intravenously infused with lactose in normal saline, at a dose rate of 0.5g/kg body weight as a function of the animal blood volumes of about 6-7% their body weights. Serum Na+ and Cl- concentrations showed significant (p

During acute Trypanosoma vivax infection of calves, produced by intravenous inoculation, the mean packed cell volume and red blood cell counts of the infected animals decreased significantly (P0.05) between Days 6 and 13 post-infection (pi). The moderately severe normocytic anaemia started to develop during the first wave of parasitaemia which occurred from Day 2 pi and peaked between Days 4 and 5 pi. The mean erythrocyte glutathione (GSH) concentration of the infected calves decreased significantly (P0.05) from 58.4 +/- 11.4 mg 100ml-1 red blood cells (RBC) on Day 0 pi to 44.5 +/- 12.8 mg 100ml-1 RBC on Day 5 pi. As the GSH values recovered on Day 6 pi and increased thereafter, another slight decrease (P0.05) in GSH concentration occurred on Day 12 pi at the second peak of parasitaemia followed by a significant (P0.05) increase to 79.1 +/- 14.6 mg 100ml-1 RBC on Day 13 pi. In the uninfected calves, the mean GSH values ranged from 47.7 +/- 7.0 to 60.8 +/- 6.8 mg 100ml-1 RBC. When washed, erythrocytes of the infected and uninfected calves were separately challenged with hydrogen peroxide. They produced comparable amounts of thiobarbituric acid reactive substances as a measure of by-products of lipid peroxidation. This suggested that the ability of the erythrocytes to prevent peroxidative injury was not reduced, because GSH regeneration was probably enhanced and the antioxidant capacity of the erythrocytes was maintained.

The course of experimental Trypanosoma vivax infection in eight Uda rams was studied. All the infected animals became parasitaemic 2 days post-inoculation and remained so throughout the study period. A three-phase disease pattern was recognized, i.e. acute, subacute and chronic stages lasting 17-85 days. The disease was characterized by fever and a terminal decrease in rectal temperature despite an increase in parasitaemia with time for rams with acute and subacute infections. Mean weight loss was most marked in subacute followed by chronic cases. Gross pathological changes observed in some infected rams with subacute and chronic trypanosomosis were oedema of the face and lower jaw, hydropericardium and atrophy of the pericardial fat. Petechial haemorrhages were observed on the surfaces of the heart and kidney of rams with acute infection. Anaemia was most severe in infected rams with acute disease, followed by those with subacute infections. Also, hypoproteinaemia was observed in all infected rams. Severe clinical findings associated with the death of all the infected rams during this study might indicate that the Uda breed of sheep in very susceptible to trypanosomosis. It is, therefore, recommended that this breed of sheep, which is strictly bred and reared in tsetse-free Sahel savannah, should not be introduced into endemic areas devoid of therapeutic cover and strict tsetse fly control.

Effect of novidium chemotherapy on elevated values of spermatozoa morphological abnormalities consequent to Trypanosoma vivax or Trypanosoma congolense infection was investigated in Zebu bulls. Six of the 12 infected animals were treated with novidium at the end of the twelfth week post-infection and studied for a period of 12 weeks post-chemotherapy. Parasites disappeared from the bloodstream within 3 days post-chemotherapy, but elevated values of spermatozoa morphological abnormalities which also decreased gradually within a period of 12 weeks post-chemotherapy were still significantly (P < 0.001) higher than the pre-infection values, values for control bulls and also considerably higher than the optimum value of 20% for most fertile bulls. Therefore, novidium chemotherapy was not effective at 12 weeks post-treatment in reducing the elevated values of spermatozoa morphological abnormalities to values found in fertile bulls and to the pre-infection levels for the bulls. The results showed that the infected bulls might still be sub-fertile 12 weeks after novidium chemotherapy owing to elevated spermatozoa morphological abnormalities.

Summary The effect of the trypanocidal drug Novidium R on elevated ejaculation time and deteriorated semen characteristics was studied in Zebu cattle infected with T. vivax and T. congolense . Two groups, comprising six bulls per group, were infected with Trypanosoma vivax or Trypanosoma congolense while three bulls served as controls. Chemotherapy was carried out 12 weeks post-infection on three bulls from each group, leaving three bulls untreated while three bulls served as uninfected controls. Blood samples from treated bulls were all negative for trypanosomes 3 days post-chemotherapy. The animals also had normal body temperature. As the study progressed, clinical signs associated with trypano-somiasis, such as anaemia and cachexia, disappeared gradually in treated bulls. There was some improvement in semen characteristics of some of the bulls at 10 weeks post-chemotherapy with Novidium R . However, all bulls infected with T. vivax or T. congolense irrespective of Novidium chemotherapy still had poor semen characteristics manifested by all or some of the following: decreased volume of semen, oligospermia, azoospermia and elevated incidence of spermatozoa morphological abnormalities. They were thus unsuitable for breeding.

Mild acid-hydrolysis of erythrocyte surface sialic acids of the trypanotolerant Ndama and the trypanosusceptible White/Fulani Zebu breeds of cattle was performed. The cleaved sialic acids from the two breeds of cattle were simultaneously subjected to polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulphate (SDS-PAGE), along with commercial standard N-acetylneuraminic acid (MW 309.28), blank gel and plasma proteins. The cleaved sialic acids migrated in the globulin fractions, as shown by the plasma protein electrophoresis. While the Ndama and the Zebu erythrocytes had one migrating band each of which coincided with the standard N-acetylneuraminic acid, the Ndama had another trailing band of sialic acid, of an estimated molecular weight of 30 kDa, which may account for the higher erythrocyte sialic acid concentrations of the Ndama. This additional band was absent in the Zebu. All these bands were readily reproducible.

Twenty-four Zebu bulls were used in a 12-wk long study. Eight bulls were infected with T. vivax , eight others with T. congolense and eight bulls served as controls. All the infected bulls developed chronic trypanosomiasis. Mean percentage base-line values prior to infection for acrosomal, sperm-head, detached heads, proximal cytoplasmic droplets, distal cytoplasmic droplets, sperm-tail, midpiece and total sperm morphological abnormalities ranged between 0.1±0.1 for acrosomal and 8.7±3.4 for total morphological abnormalities in the semen of the bulls. These values were very low and within the range of those for fertile bulls. Following infection, there was a progressive increase in the mean values of all the abnormalities. Peak percentage mean values recorded for total sperm morphological abnormalities in the course of the investigation in the bulls infected with T. vivax and T. congolense and in the controls were 95±7.2, 100±0 and 7.9±5.0, respectively. Mean percentage values throughout the duration of the investigation for control bulls were low and within the normal range for fertile bulls. These values differed (P The results indicate that trypanosomiasis due to either T. vivax or T. congolense infections can cause a marked increase in morphological abnormalities of spermatozoa which can, in turn reduce the fertility of breeding bulls.

A comparative study of haematological changes subsequent to Trypanosoma vivax and Trypanosoma congolense infections was carried out using 24 Zebu bulls during a period of 12 weeks. Eight bulls were infected with T. vivax, another eight with T. congolense and eight served as controls. Infected bulls developed chronic trypanosomiasis which was characterized by many clinical manifestations including intermittent pyrexia. Elevated rectal temperatures of up to 105 and 106°F were recorded, respectively, in all bulls infected with T. vivax or T. congolense. Mean parasitaemia was higher and more chronic in T. congolense-infected bulls and ranged between means of 0 and 3.06 in all infected bulls. There was a slight and transient drop in packed cell volume (PCV) of T. vivax-infected bulls as against a marked and more chronic drop in T. congolense-infected bulls. mean PCV of T. vivax- and T. congolense-infected bulls and controls ranged between 28 and 38, 17 and 38, and 31 and 38%, respectively. Haemoglobin (Hb) concentrations also decreased in infected bulls. The decrease was greater and more chronic in the T. congolense-infected bulls. Values ranged between means of 10.47 and 13.84, 5.44 and 14.16, and 10.24 and 14.12 g dl−1 in T. vivax- and T. congolense-infected and control bulls, respectively. Total plasma proteins also decreased in infected bulls; this was more marked in the T. congolense-infected group. Values for T. vivax-infected, T. congolense-infected and control bulls ranged between means of 7.66 and 8.99, 6.26 and 8.81, and 7.94 and 8.78 g dl−1, respectively. The results indicate that T. congolense was more pathogenic than T. vivax and caused more severe and chronic pyrexia, parasitaemia, and anaemia (as indicated by a greater decline of PCV and Hb concentrations and total plasma proteins). For all parameters studied, the T. vivax-infected bulls differed significantly from the control group (P

Trypanosoma brucei, Wamba strain, produced an acute infection in mice, and mortality was observed 2 days after the onset of parasitaemia which occurred 3–5 days postinfection. Anaemia was observed in the tail blood of the survivors. When washed erythrocytes from the heart blood were incubated in physiological saline containing 1.5% hydrogen peroxide, the erythrocytes of the infected mice produced significantly greater amounts of by-products of lipid peroxidation (measured as thiobarbituric acid reactive substances) than the erythrocytes of the control mice. This observation suggested that the infected mice may have a reduced ability in the prevention of free radical mediated lipid peroxidation in the erythrocyte membrane. It is concluded that peroxidative injury to the erythrocytes may contribute to the pathogenesis of anaemia in trypanosomosis.

Differences in the distribution and concentration of O-acetyl and glycolyl groups in erythrocyte sialic acids of trypanotolerant N'dama and trypanosusceptible Zebu cattle were investigated. Erythrocyte surface sialic acid concentrations were 25.4 +/- 5.5 mg per dl and 5.9 +/- 0.97 mg per dl in N'dama and Zebu animals, respectively. In N'damas, O-acetyl and glycolyl groups were present in concentrations of 16.4 +/- 4.3 mg per dl and 12.8 +/- 2.9 mg per dl, respectively, whereas the corresponding values in Zebus were 2.8 +/- 5.0 mg per dl and 7.6 +/- 1.7 mg per dl, respectively. The differences between N'dama and Zebu cattle in surface sialic acids and in O-acetyl and glycolyl groups were significant (P0.01 to0.001). N'dama erythrocyte sialic acids had more O-acetyl than glycolyl groups while those of Zebus had less O-acetyl than glycolyl groups. These findings may be relevant to the trypanotolerance of N'dama cattle.

One hundred and fifty-four dogs brought to the Ahmadu Bello University Veterinary Clinic for routine examination, in which an eosinophil count of 8% or higher was observed on laboratory examination, were found to be infested with one or more types of intestinal parasites. These included hookworms, tapeworms, coccidia, ascarids and spirocerca, with hookworms accounting for 51% of parasites found. Although dogs of all ages were affected, a higher incidence was observed in those under 2 years. The clinical and public health significance of these findings are emphasized.

Erythrocyte surface sialic acid concentrations were measured in the trypano-tolerant Ndama and trypano-susceptible Zebu breeds of cattle. All animals were uninfected and had no records of previous exposure to infection by African pathogenic trypanosomes. Ndama adults had significantly (P less than 0.001) higher erythrocyte surface sialic acid concentrations than Ndama calves. Ndama adults and calves had significantly (P less than 0.001) higher erythrocyte surface sialic acid concentrations than Zebu adults. There were no significant differences between the packed cell volume (PCV), haemoglobin (Hb) concentrations and total leukocyte counts (WBC) of these breeds. The finding of much higher erythrocyte surface sialic acid concentrations (about 7-fold) in the Ndama than in the Zebu is discussed in relation to the induction of anaemia by trypanosome sialidase in both breeds and to how a relative trypano-tolerance may occur in the Ndama.

Morphological abnormalities of spermatozoa were evaluated in ejaculates of 27 healthy bulls aged between one and a half and three and a half years from January to December of 1982. The year was divided into three seasons: (1) January-April (partly harmattan, dry and hot), (2) May-August (rainy), and (3) September-December (dry and partly harmattan). All the bulls showed seasonal variations in the incidence of sperm-head abnormalities, detached-heads, proximal cytoplasmic droplets and total morphological abnormalities. The means for total morphological abnormalities of the spermatozoa were 21.5%, 10.6% and 11.3% for seasons 1, 2 and 3, respectively (P

Erythrocyte surface and free serum sialic acid concentrations were determined during experimental Trypanosoma vivax infection in cattle. All infected calves developed mild trypanosomiasis, with significant decreases in mean packed cell volume occurring 15, 16, 20, 22 and 24 days after infection. The anaemia was preceded by significant decreases in mean erythrocyte surface sialic acid concentrations on days 7, 13 and 14, with yet another significant decrease on day 31 after infection. These decreases in erythrocyte surface sialic acid concentrations coincided with the parasitaemic waves. Free serum sialic acid concentration, however, showed an increase, though non-significantly, on day 8, which coincided with both a decrease in erythrocyte surface sialic acid and the initial parasitaemic wave. It is postulated that the early anaemia observed in infected animals may be attributable to the activities of the circulating trypanosomes which produce neuraminidase which, in turn, cleaves off surface sialic acid, thus rendering the erythrocyte more prone to phagocytosis by the recticuloendothelial system.

The course of trypanosomiasis was observed over a period of 68 days in eight red sokoto goats experimentally infected with Trypanosoma vivax strain Y58. The goats developed parasitaemia five days after infection; the intensity of parasitaemia varied within and between individual goats. The course of the disease was acute, subacute or chronic. Anaemia was the principal clinicopathological feature of the disease. The rate of development of anaemia was not related to the degree of parasitaemia. Other clinical signs included emaciation, weakness, rough hair coat, profuse lacrimation and development of corneal opacity. Bone marrow of infected goats showed marked erythroid hyperplasia. Erythrophagocytosis and haemosiderosis in the bone marrow, liver and spleen were the principal histopathogical features in infected goats.

Sixty zebu heifers were divided into three equal groups and reared on isocaloric diets but on different levels of protein. The protein levels were 19.17% (high), 13.37% (medium; NRC recommendations) and 8.3% (low). All animals were examined weekly per rectum for the presence of follicles and corpora lutea and also checked daily for standing heat. The presence of a mature corpus luteum was considered to indicate the attainment of puberty. Body weight and pelvic dimensions were taken at biweekly intervals. Intact bulls were introduced to heifers after they reached puberty and once they reached 200 kg live weight. Pregnancy diagnosis was carried out at 60, 90 and 120 days following introduction of bulls. Mean age at puberty for heifers in the high protein group (570.4 days), medium protein group (640.8 days) and low protein group (704.2 days) differed significantly (P

Eight Zebu cattle were infected with Trypanosoma vivax stock Y58, while 8 served as uninfected controls. The infected animals developed early leukopenia due to concomitant lymphopenia and neutropenia. It is suggested that an increase in trypanosomal antigens and neuraminidase in the infected cattle at this time may have an effect on peripheral leukocytes.

Haemoglobin-binding protein (Haptoglobin, Hp) was assayed in the sera of control and zebu calves with acute T. vivax infection. Hp in control Zebu calves ranged between 123.5 and 236.5 mg dl −1 while Hp in the infected calves was too low to measure or absent. It was suggested that absence of Hp in the infected calves may be as a result of gradual intravascular haemolysis and removal of the Hp-Hb complex by the reticulo-endothelial system.

Haematological values of Yankasa and Udah sheep were determined in three clinically healthy flocks and a fourth flock with mixed helminthiasis, predominantly haemonchosis. Values for Hb, PCV, RBC and WBC from the healthy flocks were similar. They were, however, lower than reported values for sheep in temperate zones except the WBC values which were higher. These parameters were lower in the infected flock and had a wider spread. It was concluded that haematological values from the clinically healthy flocks could serve as a baseline for interpreting haematological data from diseased local sheep. It is suggested that management and health status are more important than breed for differences in haematological values.

The effect of trypanosomiasis on reaction time and semen characteristics of 24 Zebu bulls was studied. Eight of the bulls were infected with T. vivax , another eight with T. congolense and the remaining eight bulls served as controls. The preinfection mean value of the rectal temperature was 101.0 °F, and this rose to a mean of between 104·5 and 105·5 °F in the infected animals. Concurrently the latter animals exhibited signs of anaemia shown by pale mucous membranes and decreased PCV, weight loss, lethargy, weakness and dullness. The reaction time of semen collection significantly increased from a pre-infection mean value of 24·3–60·13 seconds to a mean of 14·25–267·25 seconds within 12 weeks post-infection. Semen characteristics deteriorated progressively within the same period in the infected bulls. There were highly significant and drastic decreases in sperm concentration and volume of semen and increases in abnormal sperm cells. By the sixth week, the 16 infected bulls were unfit for breeding because of very poor semen characteristics. Deterioration continued to the end of the investigation. The present results indicate that T. congolense appeared more virulent and devastating in its effect on the reaction time (ejaculation time) and on the destruction of germinal epithelium which resulted in poor semen quality. This is of particular significance to livestock farmers in trypanosome endemic regions, the practical implication being infertility in infected bulls.

The variations with age in serum iron concentration and iron-binding capacity in zebu cattle were investigated. Serum iron concentration was lower in calves from birth to four weeks of age than in older cattle. Total iron-binding capacity decreased while percentage saturation increased with advancing age.