Bulgarian Journal of Veterinary Medicine (BJVM)
ISSN 1311-1477
Bulgarian Journal of Veterinary Medicine
VOL. 8, No 1, MARCH, 2005
CONTENTS
N. V. GEORGIEVA
Oxidative stress as a factor of disrupted ecological oxidative balance in biological systems – a review13
FULL TEXTa. t. atanasov
ALLOMETRIC RELATIONSHIP BETWEEN the length OF PREGNANCY AND BODY WEIGHT IN MAMMALS23
FULL TEXTA. MUÑOZ, K. SATUE, S. ROVIRA, R.G. LUCAS & M. BENITO
Electrocardiographic Ventricular Repolarisation Processes In Andalusian Horses Before And After
Physical Training35
FULL TEXTI. Penchev Georgiev
Alterations in chemical composition of colostrum in relationship to post-partum time41
FULL TEXTS. Yotov
Diagnostics of early pregnancy in Stara Zagora dairy sheep breed47
FULL TEXTI. TAVCIOVSKA-VASILEVA & K. REBOK
ULTRASTRUCTURAL CHANGES IN SERTOLI CELLS IN OHRID TROUT – SALMO LETNICA (KARAMAN) DURING THE PRESPAWNING AND POSTSPAWNING PERIOD59
FULL TEXT69
FULL TEXTV. V. Uzunova, A. N. Tolekova, G. S. Ilieva, K. I. Trifonova
& A. P. Logofetov
RENIN‑ANGIOTENSIN SYSTEM AND LIPID PEROXIDATION77
honorabiles
Published by the Trakia University, Faculty of Veterinary Medicine,
6000 Stara Zagora, Bulgaria
Volume 8, Number 1, March 2005, Summaries
Georgieva, N. V., 2005. Oxidative stress as a factor of disrupted ecological oxidative balance in biological systems – a review. Bulg. J. Vet. Med., 8, No 1, 1-11.
Recently, reactive oxygen species (ROS) received a particular attention as they are supposed to participate in some pathological complications and toxic side effects with a still unknown importance. ROS are known to be involved in carcinogenesis, tumour initiation, tumour growth, the triggering and realization of programmed cellular death, apoptosis induced by exterior factors such as chemical agents, environmental pollutants, cytotoxic and hepatotoxic drugs, ionized radiation, UV irradiation etc. In low concentrations, ROS are necessary for numerous physiological processes and normally, there exists an equilibrium between ROS and systemic antioxidants. The state of balance between ROS generation and the protection capacity of endogenic antioxidant defense of biological systems could be specified as ecological oxidative balance (equilibrium) (EOB). In this state, they are maximally protected against toxic oxidative influences. All endogenic and exogenic sources of uncontrolled ROS production result in oxidative stress that impairs the equilibrium to a considerable extent. When EOB is disturbed, the biological systems are not protected against oxidative radical effects because of the impaired interrelationship between the activity and the intracellular levels of endogenic antioxidants and prooxidants, resulting in toxic damage, disease, aging or death of biological systems.
Key words: ecologic oxidative balance (EOB), oxidative stress, reactive oxygen species (ROS)
Atanasov, A. T., 2005. Allometric relationship between the length of pregnancy and body weight in mammals. Bulg. J. Vet. Med., 8, No 1, 13-22.
The relationship between the length of pregnancy and the body weight in mammals - Metatheria and Placentalia, including 17 orders of animals with body weights ranging from 8 g to 15 t was investigated. It was found out that an allometric relationship existed, that could be described by the equation T = 7.545´M0.2689, where T - pregnancy length in days, М – body weight in grammes, 7.545– allometric coefficient, 0.2689 – power allometric coefficient.
Key words: body weight, length of pregnancy, mammals
Muñoz, A., K. Satue, S. Rovira, R. G. Lucas & M. Benito, 2005. Electrocardiographic ventricular repolarisation processes in Andalusian horses before and after physical training. Bulg. J. Vet. Med., 8, No 1, 23-34.
Equine ventricular repolarisation wave can be influenced by many physiological and pathological factors. T wave abnormalities have been related to a shorter time for ventricular filling, reduced stroke volume, cardiac output and exercise performance in racehorses. The present research performed electrocardiographic recordings in 14 four-year-old male Andalusian horses, when they were untrained and after three months of an aerobic training programme. Leads I, aVF, V10, V1R, V3R, V1L and V3L were used. It was aimed to assess the incidence of abnormal T waves in this breed, according to the criteria of abnormalities established for other equine breeds, to evaluate if the changes induced by training in the T wave are the same that those reported in the athletic heart syndrome in canine and human athletes and, to analyse if the abnormal T waves could have been related to changes in the plasma concentrations of Na, K, and Cl, since these electrolytes are involved in the cardiac electrical processes.
It was found out that the incidence of abnormal T waves was quite high in the Andalusian breed, especially in the precordial leads. Moreover, the incidence of abnormal T waves increased in precordial leads and decreased in lead I and aVF after training. The abnormal T waves after training were shorter and had the same voltage, changes which were different to those presented for the athlete’ heart syndrome. The horses with abnormal T waves had higher plasma K concentrations, both before and after training. Plasma Na and Cl concentration at rest decreased after training. Plasma Na concentrations were positively related to T wave duration and negatively to T wave voltage.
Key words: electrocardiography, heart, horses, performance, training
Georgiev I. Penchev, 2005. Alterations in chemical composition of colostrum in relationship to post-parturn time. Bulg. J. Vet. Med., 8, No 1, 35-39.
Experiments were designed to study the alterations in colostrum composition in relationship to post-partum time in dairy cows differing in milk yield. Two groups of 5 cows each, with high or low milk yield, respectively were used. Colostrum samples were collected on day 1 and day 3 after birth. Concentration of the major colostrum constituents (milk protein, lactose, dry matter and solid non-fat extract) changed significantly after birth, the levels on day 3 being similar to those of mature milk. The most significant changes were those in the concentration of milk protein, that on day 3 was more than twice lower as compared to the first portion of colostrum. There was no effect of milk secretion intensity on chemical composition of colostrum.
Key words: colostrum composition, dairy cows, milk yield
Yotov, S., 2005. Diagnostics of early pregnancy in Stara Zagora dairy sheep breed. Bulg. J. Vet. Med., 8, No 1, 41-45.
The study was performed on 70 sheep from the Bulgarian Stara Zagora Dairy breed, aged 2-5 years and weighing 60-65 kg. The sheep were artificially inseminated after synchronization of the oestrus by vaginal sponges containing flurogestone acetate and PMSG. At post insemination days 20, 27 and 35, a transabdominal ultrasonographic test for pregnancy was performed with the Aloka SSD 500 Micrus equipment and a 5 MHz linear transducer. The accuracy, sensitivity and specificity of the method were evaluated. An accuracy of 87.1% at post insemination day 27 that increased up to 98% at post insemination day 35 was detected. It was found out that the increase in uterine lumen diameter and the size of the embryo with detection of cardiac activity were reliable criteria for ruling out the occurrence of early embryonal, resp. foetal death.
Key words: early pregnancy, sheep, ultrasonography
Tavciovska-Vasileva, I. & K. Rebok, 2005. Ultrastructural changes in Sertoli cells in Ohrid trout – Salmo letnica (Karaman) during the prespawning and postspawning period. Bulg. J. Vet. Med., 8, No 1, 47-57.
A cytological analysis based on ultrastructural findings in some regions of Ohrid trout` testes - Salmo letnica (Karaman) in the prespawning and postspawning period, with a special emphasis of Sertoli cells, was performed.
Sertoli cells, being an integral part of the seminiferous lobules underwent considerable changes, which influenced their cytomorphological features. The cells with endotheliomorphic appearance, characteristic for the prespawning period, gradually increase their dimensions. Lipid vacuoles of different size were noticed in their cytoplasm, while the nuclei acquired a polymorphic appearance.
In the seminiferous lobules with rare sperm residues Sertoli cells underwent further changes which caused their involution. The degenerative changes of Sertoli cells were manifested by an extreme vacuolisation, mitochondria with desintegrated crysts or mitochondria in degeneration (with widened crysts and thickened matrix), by desorganised endoplasmic reticulum, digestive vacuoles (autophagosomes), “myeline-like” structures and lysed cytoplasmic regions. The above mentioned changes were followed by karyopyknosis, complete degeneration and delamination of cells from the wall of the seminiferous lobules, lysis and detritus formation (Sertoli necrotic material) in the lumen of the lobules.
The degeneration of Sertoli cells was followed by destruction of the basal membrane of the lo-bules.
Key words: Ohrid trout, Salmo letnica (Karaman), Sertoli cells
Waiswa, C., 2005. Porcine trypanosomiasis in Southeastern Uganda: Prevalence and assessment of therapeutic effectiveness. Bulg. J. Vet. Med., 8, No 1, 59-68.
This study aimed at investigating the prevalence of trypanosomiasis and the usefulness of diminazene aceturate and isometamidium chloride in the treatment of pigs infected with Trypanosoma brucei sub-group.
Whole blood was collected from pigs kept in two disease endemic areas, with riverine and open savannah environments.
The prevalence of trypanosomiasis was recorded at 8.1% in the riverine environment as compared to the 2.1% in the open savannah environment and the infections in the former were significantly higher (P < 0.001).
All pigs that received a treatment of isometamidium chloride (Samorin®) at 1 mg/kg body weight did not show relapse when followed up to one month post treatment using microscopy. However, relapses were recorded among pigs treated with diminazene aceturate (Berenil®) at a dose rate of 7 mg/kg body weight and no relapses were recorded in those treated with 14 mg/kg body weight.
From this investigation, it is apparent that the trypanosome prevalence among pigs kept under the riverine environment is higher than those kept under the open savannah. In addition, 1 mg/kg and 14 mg/kg isometamidium chloride and diminazene aceturate respectively should be adopted for the treatment of trypanosome infections among the pigs in the trypanosomiasis endemic areas.
Key words: haemoglobin, PCV, pigs, therapy, trypanocidal agents, trypanosomiasis
Uzunova, V. V., A. N. Tolekova, G. S. Ilieva, K. I. Trifonova & A. P. Logofetov, 2005. Renin-angiotensin system and lipid peroxidation. Bulg. J. Vet. Med., 8, No 1, 69-75.
The state of renin-angiotensin system (RAS) activation influences the production of reactive oxygen species (ROS). This study aimed to investigate the correlation between plasma renin activity (PRA) and malondialdehyde (MDA) as a marker of lipid peroxidation. The experiment was carried out on male Wistar rats, treated with nifedipine, nicardipine and captopril. After application of all drugs, PRA was significantly increased compared to controls (P<0.05) from the 1st to the 7th hour. Significant differences (P<0.05) between MDA levels in controls and treated groups were found at hours 1, 3 and 5 for all three drugs. Different degrees of positive correlation among studied parameters were established in the groups. All three drugs led to a marked increase in lipid peroxidation. Nifedipine and nicardipine were expected to have such an effect because they cause accumulation of angiotensin II (Ang II), which is known to have a prooxidative action. Captopril however is supposed to have antioxidant effect because it lowers angiotensin II. The increase in MDA observed in this study could be linked to the “effect of escape" of the blockade.
Key words: captopril, lipid peroxidation, MDA, nicardipine, nifedipine, RAS