The effect of pegbovigrastim administration on the nonspecific immunity of calves.

BACKGROUND: Prevention of diseases in the early rearing of calves is important, particularly because disease occurrence most often requires antimicrobial administration but reduction of their use in animals is a priority. Pegbovigrastim is known for its use as an immunoregulator in cows and heifers, but the effect of its administration on calves has not been fully investigated. OBJECTIVES: Investigate whether administration of pegbovigrastim effectively stimulates nonspecific immunity in healthy calves. ANIMALS: Eleven clinically healthy 5-week-old calves. METHODS: Prospective observational study. Calves were randomly allocated to an experimental or control groups to receive pegbovigrastim or the same volume of phosphate-buffered saline twice over a 7-day period. To evaluate nonspecific immunity, the numbers of total leukocytes and cells in the appropriate cell fractions were determined. Cytometric analyses were carried out to identify cells expressing CD11b and to evaluate the phagocytic and oxidative burst activities of granulocytes and monocytes. Myeloperoxidase (MPO) and selected cytokines were assayed using ELISA. RESULTS: Pegbovigrastim significantly increased the number of total leukocytes and of cells in all of the examined subsets (P < .05). The phagocytic activity of leukocytes expressed as mean fluorescence intensity was significantly potentiated after pegbovigrastim administration (P < .05). The cytokine response was modulated by pegbovigrastim administration toward anti-inflammatory activity. CONCLUSIONS AND CLINICAL IMPORTANCE: Pegbovigrastim effectively stimulated nonspecific immunity in clinically healthy calves, which in the long term could make the prevention of diseases during early rearing possible by strengthening the immune defense mechanisms of the host.

The Effect of Pegbovigrastim Injection on Phagocytic and Oxidative Burst Activities of Peripheral Blood Granulocytes and Monocytes in Calves Challenged with Mycoplasma bovis.

Mycoplasma bovis (M. bovis) is an important pathogen affecting cattle, causing various diseases including pneumonia which mainly occurring in calves. Control of M. bovis infections is difficult due to the lack of commercial vaccines in most parts of the world and increasing trends of antimicrobial resistance in field isolates of the pathogen; therefore, it seems reasonable to look for new solutions for the prevention of the infection. Pegbovigrastim is a pegylated form of naturally occurring circulating cytokine in cattle that affects bovine leukocytes and some cell functions. Most studies on pegbovigrastim have focused on reducing the occurrence of mastitis and other diseases occurring during the periparturient period in cows, while this study attempts to use pegbovigrastim in the prevention of respiratory diseases in calves, which are largely caused by M. bovis. Based on previous observations on the immunostimulatory properties of pegbovigrastim in cattle, for the first time, the effect of its injection on the number and phagocytic and oxidative burst activities of peripheral blood granulocytes and monocytes in calves experimentally infected with M. bovis was investigated. Pegbovigrastim administration in the calves significantly stimulated an increase in peripheral blood granulocyte and monocyte counts and phagocytic activity of the cells, especially granulocytes, which was also generally expressed in the course of M. bovis infection. In response to pegbovigrastim administration, a general increase in the oxygen burst activity of the cells was observed. This effect was also shown despite ongoing infection with M. bovis which, taken together, may indicate a beneficial effect of pegbovigrastim injection on the immunity of the affected animals.

Effect of Supplementation with the Combination of Se-Enriched Lentinula edodes Mycelium, Exogenous Enzymes, Acidifiers, Sodium Butyrate and Silicon Dioxide Nanoparticle Feed Additives on Selected Parameters in Calves.

During the initial months of calves' lives, the young animals are exposed to bacterial and viral infections, and during this period, crucial physiological changes take place in their organisms. Offering calves feed additives that will have a beneficial influence on their organisms and improve their growth while reducing the morbidity rate is the optimal task of feeding. This is the first study to investigate the effect of experimental supplementation for calves with the combination of two feed additives­one containing Lentinula edodes enriched with selenium (Se), and the second containing pancreatic-like enzymes, fat-coated organic acids, sodium butyrate, and silicon dioxide nanoparticles­on the serum Se concentration, selected immune parameters, and the average daily gains in the calves. During the study, the serum Se concentration was examined by means of inductively coupled plasma mass spectrometry, and the immunoglobulin and cytokine concentrations with ELISA assays. The white blood cell (WBC) count with leukocyte differentiation was examined with the use of a hematological analyzer, and the percentages of subpopulations of T lymphocytes and monocytes, phagocytic activity, and oxidative burst of monocytes and granulocytes with the use of a flow cytometer. The average daily gains of the calves were also evaluated. In summary, the supplementation of the experimental calves with the combination of two feed additives resulted in significantly higher serum Se concentrations, and the immune systems of the calves were not suppressed while the examined feed additives were being delivered. Although not statistically significant, some positive effects on the calves were seen: a tendency towards the improvement of some of the immune parameters evaluated, and a tendency for higher average daily gains in the calves.

Occurrence of Bovine Coronavirus and other Major Respiratory Viruses in Cattle in Poland.

Introduction: Bovine coronavirus (BCoV) is a causative agent of enteric and respiratory diseases in cattle. Despite its importance for animal health, no data is available on its prevalence in Poland. The aim of the study was to determine the virus' seroprevalence, identify risk factors of BCoV exposure in selected cattle farms and investigate the genetic variability of circulating strains. Material and Methods: Serum and nasal swab samples were collected from 296 individuals from 51 cattle herds. Serum samples were tested with ELISA for the presence of BCoV-, bovine herpesvirus-1 (BoHV-1)- and bovine viral diarrhoea virus (BVDV)-specific antibodies. The presence of those viruses in nasal swabs was tested by real-time PCR assays. Phylogenetic analysis was performed using fragments of the BCoV S gene. Results: Antibodies specific to BCoV were found in 215 (72.6%) animals. Seropositivity for BCoV was more frequent (P>0.05) in calves under 6 months of age, animals with respiratory signs coinfected with BoHV-1 and BVDV and increased with herd size. In the final model, age and herd size were established as risk factors for BCoV-seropositivity. Genetic material of BCoV was found in 31 (10.5%) animals. The probability of BCoV detection was the highest in medium-sized herds. Polish BCoVs showed high genetic homology (98.3-100%) and close relatedness to European strains. Conclusion: Infections with BCoV were more common than infections with BoHV-1 and BVDV. Bovine coronavirus exposure and shedding show age- and herd density-dependence.

A Pilot Study on The Effect of a Novel Feed Additive Containing Exogenous Enzymes, Acidifiers, Sodium Butyrate and Silicon Dioxide Nanoparticles on Selected Cellular Immune Indices and Body Weight Gains of Calves.

INTRODUCTION: The rearing of calves is a difficult period for farmers due to health problems to which the animals are prone this time. Since the use of antibiotics as growth promoters has been forbidden, various innovative feed additives have been tested in many countries around the world. MATERIAL AND METHODS: In this study, experimental (E) calves were supplemented with a novel feed additive consisting of the pancreatic-like enzymes protease and lipase, a fat-coated mixture of organic fumaric, malic, citric and sorbic acids, sodium butyrate and silicon dioxide nanoparticles. Control (C) calves received feed without additive. During the supplementation, white blood cell (WBC) counts with leukocyte differentiation, percentages of B lymphocytes and T lymphocytes and their subpopulations, phagocytic activity and oxidative burst of circulating monocytes and granulocytes were examined. Body weight (b.w.) gains of the calves were also monitored. RESULTS: The WBC counts in the E and C calves were within the reference ranges throughout the study. In the analysis of the percentages of the lymphocyte subpopulations, phagocytic activity and oxidative burst, no statistically significant differences were reported between the E and C groups. However, higher average daily body weight gains were obtained for the E calves. CONCLUSION: The study revealed that the examined feed additive did not modulate the immune response of the calves significantly. The tendency to higher daily average b.w. gains in the E calves than in the C calves suggests a beneficial effect of this feed additive.

Mycoplasma bovis Infections-Occurrence, Diagnosis and Control.

Mycoplasma bovis is a cause of bronchopneumonia, mastitis and arthritis but may also affect other main organs in cattle such us the eye, ear or brain. Despite its non-zoonotic character, M. bovis infections are responsible for substantial economic health and welfare problems worldwide. M. bovis has spread worldwide, including to countries for a long time considered free of the pathogen. Control of M. bovis infections is hampered by a lack of effective vaccines and treatments due to increasing trends in antimicrobial resistance. This review summarizes the latest data on the epizootic situation of M. bovis infections and new sources/routes of transmission of the infection, and discusses the progress in diagnostics. The review includes various recommendations and suggestions which could be applied to infection control programs.

Preliminary study on Se-enriched Lentinula edodes mycelium as a proposal of new feed additive in selenium deficiency.

The presence of selenium in European soil is low and this causes its deficiency in livestock and, in consequence, in humans. This study aimed to obtain Lentinula (L.) edodes mycelium with the maximum content of selenium. This species was used for experiment based on its documented medicinal properties. Calves were fed with selenium-enriched L. edodes mycelium, and serum selenium concentration, average daily weight gains and selected immune parameters were estimated. The selenium-enriched mushroom was found to be safe based on cytotoxicity tests (MTT and LDH tests) and for this reason it was used for further experiments. The mean quantity of selenium in the serum of calves fed with selenium-enriched L. edodes mycelium was significantly higher than that of control calves. Additionally, the calves fed with selenium-enriched L. edodes mycelium had higher body weight gains than those of control calves. White blood cell counts and subpopulations of lymphocytes in the experimental and control calves were within the reference range. The administration of L. edodes enriched with selenium had a beneficial effect on state of health of the calves.

Analysis of the Leukocyte Response in Calves Suffered from Mycoplasma bovis Pneumonia.

Mycoplasma bovis is known to be a cause of chronic pneumonia in cattle. To date, the disease pathomechanism has not been fully elucidated. Leukocytes play a key role in host antimicrobial defense mechanisms. Many in vitro studies of the effect of Mycoplasma bovis (M. bovis) on leukocytes have been performed, but it is difficult to apply these results to in vivo conditions. Additionally, only a few studies on a local immune response in M. bovis pneumonia have been undertaken. In this study, the experimental calf-infection model was used to determine the effect of field M. bovis strains on changes of the peripheral blood leukocyte response, including phagocytic activity and oxygen metabolism by cytometry analyses. An additional aim was to evaluate the lung local immunity of the experimentally infected calves using immunohistochemical staining. The general stimulation of phagocytic and killing activity of peripheral blood leukocytes in response to the M. bovis infection points to upregulation of cellular antimicrobial mechanisms. The local immune response in the infected lungs was characterized by the T- and B-cell stimulation, however, most seen in the increased T lymphocyte response. Post-infection, strong expression of the antigen-presenting cells and phagocytes also confirmed the activation of lung local immunity. In this study-despite the stimulation-both the peripheral and local cellular antimicrobial mechanisms seem to appear ineffective in eliminating M. bovis from the host and preventing the specific lung lesions, indicating an ability of the pathogen to avoid the host immune response in the M. bovis pneumonia.

Preliminary study on the effects of enrofloxacin, flunixin meglumine and pegbovigrastim on Mycoplasma bovis pneumonia.

BACKGROUND: Mycoplasma bovis is a causative agent of disease in cattle causing many clinical conditions. Currently there are no commercial M. bovis vaccines in Europe and treatment is difficult with decreased antimicrobial susceptibility of M. bovis field isolates. Using an M. bovis calf infection model the effectiveness of enrofloxacin given alone; in combination with flunixin meglumine, a nonsteroidal anti-inflammatory drug; and a group with an additional treatment of pegbovigrastim, an immunostimulator, was evaluated. RESULTS: Enrofloxacin given alone stimulated a strong immune response, reduced the clinical manifestation and lung lessions of the M. bovis infection. In contrast the combination therapy appeared ineffective. CONCLUSIONS: In this experiment enrofloxacin given alone appeared to be the most effective treatment of the M. bovis affected calves, whereas co-administration with flunixin meglumine, and pegbovigrastim was not beneficial in this trial.

Saponin-based Mycoplasma Bovis Vaccine Containing Lysozyme Dimer Adjuvant Stimulates Acute Phase Response in Calves.

INTRODUCTION: Mycoplasma bovis is known as a causative agent of many disorders in cattle. In Europe, there is still a lack of commercial vaccines against M. bovis infection. Acute phase response (APR) is a non-specific host reaction to infection, most seen in changes in production of acute phase proteins. The aim of this study was to analyse APR in calves administered with an experimental M. bovis vaccine. MATERIAL AND METHODS: Twelve healthy female calves were divided into two equal groups: experimental and control. The experimental vaccine containing the field M. bovis strain and two adjuvants such as saponin and lysozyme dimer was subcutaneously administered to the experimental group. Phosphate buffered saline was taken as the placebo and given to the control group by the same route as the vaccine. Blood samples were collected prior to the study (day 0), then daily up to day 7, and then each seven days until day 84 post vaccination. The concentrations of serum amyloid A (SAA), haptoglobin (Hp), interferon-γ (IFN-γ), and inteleukin-4 (IL-4) were determined using commercial ELISA kits. RESULTS: Following the vaccination, a significant increase in SAA, Hp, and IFN-γ concentrations was observed when compared to the unvaccinated calves, whereas the IL-4 concentration was not detectable. CONCLUSION: The experimental saponin-based M. bovis vaccine containing lysozyme dimer adjuvant visibly stimulated the APR in the calves, and some specific cytokines (Th1-dependent) directly involved in this response.

Analysis of the immune response of calves to various saponin-based adjuvants for an experimental Mycoplasma bovis vaccine.

Mycoplasma bovis is a primary infectious agent of many disorders in cattle including bovine respiratory disease. No commercial vaccines against M. bovis are available in Europe. The immune response of calves to three saponin-based adjuvants combined with a field Polish M. bovis strain was evaluated. Four groups of six calves each were injected subcutaneously with the M. bovis strain combined with either saponin, saponin + Emulsigen®, saponin + Emulsigen® + alphatocopherol acetate, or with phosphate-buffered saline as control group. Blood and nasal swab samples were collected up to day 84 post injection. All formulations effectively stimulated the humoral and the cellular immune response of the calves, but the course of the response depended on the adjuvant formulation. These immunological data provide additional information supporting the findings of previous M. bovis saponin and Emulsigen® vaccine challenge studies to facilitate the development of successful M. bovis vaccines.

Applicability of the Protein-lipid Profile and Activity of Lactate Dehydrogenase Isoenzymes for Diagnosing Nutritional Muscular Dystrophy in Calves.

INTRODUCTION: In calves, hyposelenosis degenerates skeletal muscles in different parts of the body. The extent of damage to muscle cells can be diagnosed by determining the activity of creatine kinase (CK), aspartate aminotransferase (AST), and lactate dehydrogenase (LDH). The aim of this study was to analyse variations in the serum levels of LDH isoenzymes in calves with nutritional muscular dystrophy (NMD), to determine the applicability of this parameter for diagnosing NMD, and to describe the influence of hyposelenosis on total protein (TP), triglyceride (TG), and cholesterol (CHOL) levels. MATERIAL AND METHODS: Two groups of calves (n = six animals per group) were used. After birth, control group calves (SC) were intramuscularly administered 10 ml of a preparation containing selenium (Se) and vitamin E, and experimental group animals (SE) that were not injected. Blood was collected after 5, 15, and 25 days, and the concentrations of Se, vitamin E, TP, TG, and CHOL and the activity of glutathione peroxidase (GSH-Px), CK, and LDH fractions were determined. RESULTS: Hypocholesterolaemia and elevated TG levels were found in SE group calves whose LDH fractions revealed a significant increase in LDH4 and LDH5 activity and a decrease in LDH1 activity when electrophoretically separated. CONCLUSION: Nutritional muscular dystrophy is accompanied by hypocholesterolaemia and elevated TG levels caused by muscle lipolysis. LDH4 and LDH5 activity parameters assist early diagnosis of NMD in calves.

Results of a 16-week Safety Assurance Study with Rats Fed Genetically Modified Bt Maize: Effect on Growth and Health Parameters.

INTRODUCTION: The influence of feeding genetically modified MON 810 hybrid maize on the growth and haematological and biochemical indices of rats was tested. MATERIAL AND METHODS: Two conventional (non-GM) and two test (MON 810) lines of maize were used in semi-purified diets at the level of 40% w/w. The non-GM I, MON 810 I, non-GM II, and MON 810 II maize lines were near-isogenic. A total of 40 male 6-week-old Wistar-derived rats were assigned to four equal feeding groups corresponding to the four maize lines for 16 weeks. Overall, health, body weight gain, clinical pathology parameters, gross changes, and appearance of tissues were compared between groups. RESULTS: There were no statistically significant differences in the weight gain or relative organ weights of rats, but there were some non diet-related histopathological changes in the liver, kidneys, and spleen. Except for creatinine level, no diet-related effects were observed in haematology or most of the biochemical indices. Transgenic DNA of MON 810 maize was not detected in the tissues or faeces nor in the DNA of E. coli isolated from the rectum digesta of rats given transgenic feeds. In our experiment, various metabolic indices of rats fed non-GM diets or genetically modified (MON 810) maize for 16 weeks were similar. No adverse nutrition-related health effects were detected. CONCLUSION: MON 810 maize seems to be as safe as the conventional maize lines.

T- and B-cell Response Analysis Following Calf Immunisation with Experimental Mycoplasma Bovis Vaccine Containing Saponin and Lysozyme Dimer.

INTRODUCTION: Mycoplasma bovis is a well-known cause of various disorders in cattle, such as pneumonia, arthritis, mastitis kerato-conjunctivitis, pharyngitis, laryngitis, otitis media, meningitis, and reproductive disorders. There are no commercial vaccines against M. bovis in Europe, therefore, experimental ones are still under investigation. The aim of this study was to evaluate the effect of experimental M. bovis vaccine, containing the Polish field M. bovis strain as well as saponin and lysozyme dimer adjuvants, on the T- and B-cell response in calves. MATERIAL AND METHODS: The study was carried out on 12 calves divided into two equal groups: experimental and control. The experimental group was subcutaneously injected with the vaccine composed of the field M. bovis strain as well as saponin and lysozyme dimer as adjuvants, whereas the control one received phosphate buffered saline (PBS). The blood samples were collected prior to the study (day 0), then in 24 h intervals up to day 7 and then each 7 days until day 84 post immunisation. The T- and B-cell response as CD2+ (T-cells), CD4+ (T-helper cells), CD8+ (T-cytotoxic cells), and WC4+ (B-cells) markers was analysed using flow cytometry. RESULTS: In response to the immunisation, the general stimulation of T-cell was observed, the most seen in an increase in CD8+ subpopulation. Similarly, a visible rise in the percentage of WC4+ cells was registered in the vaccinated calves when compared to the control animals. CONCLUSION: This study demonstrated that the novel experimental M. bovis vaccine containing saponin and lysozyme dimer effectively stimulated the cell-mediated immunity in the calves.

An experimental vaccine composed of two adjuvants gives protection against Mycoplasma bovis in calves.

Mycoplasma bovis is a major pathogen affecting cattle causing bronchopneumonia, mastitis, and other disorders. Only autogenous vaccines made specifically for individual farms are available in parts of Europe and the United States. A novel experimental vaccine composed of a field M. bovis isolate combined with saponin and Emulsigen(®) adjuvants was evaluated. Eighteen 3-4 week old calves were placed in three equal groups: vaccinated (Vac), positive control (PC) and negative control (NC). The Vac calves were subcutaneously injected with 8ml of the vaccine; the PC and NC calves received phosphate buffered saline (PBS). Three weeks later the Vac and PC calves were challenged with a virulent M. bovis strain, the NC group received PBS. Throughout the study clinical observations, microbiology and immunological tests were carried out. Three weeks post challenge two calves from each group were euthanased for necropsy and histopathological examination. The vaccine effectively stimulated the humoral immune response, with high titres of anti-M. bovis specific antibodies and total Ig concentration. This vaccine also intensified the IgA response. A clinically protective effect of the vaccine was demonstrated as it also reduced the gross pathological lung lesions and nasal shedding of M. bovis.

Flow cytometry follow-up analysis of peripheral blood leukocyte subpopulations in calves experimentally infected with field isolates of Mycoplasma bovis.

Changes in peripheral blood leukocyte subpopulations were investigated in calves challenged intratracheally with three different Mycoplasma bovis isolates in Groups E1, E2, and E3. The controls received a placebo. Blood samples were collected before challenge and then at days 1 to 7, 14, 21 and 28. White blood cells (WBC), polymorphonuclear leukocytes (PMNLs), lymphocytes (LYMs), monocytes, eosinophils and basophils (mid-size cells, MID), as well as CD2(+), CD4(+), CD8(+), WC4(+) lymphocyte subsets with CD4:CD8 ratio were also analysed. A transient increase of WBC and PMNLs in all challenged calves was observed on day 1. Increased LYM counts were observed in E1 throughout the study, whereas in E2 the LYM counts were higher only between days 14 and 28, and consistently lower in E3. The MID count had broadly comparable values for all groups. Stimulation of the CD2(+) response was observed in E2 and E3 in contrast with E1 which had a lower CD2(+) throughout. The CD4(+) response was dominant in E1 and E2, whereas in E3 a parallel CD4(+) and CD8(+) stimulation was observed. The B-cell response (WC4(+)) and an increased CD4:CD8 ratio was most apparent in E1. The main host responses to M. bovis infections are a stimulation of CD4(+) cells and an enhancement of the WC4(+) response.

Stimulation and analysis of the immune response in calves from vaccinated pregnant cows.

The effect of vaccinating pregnant cows with an inactivated vaccine against Mannheimia haemolytica, BRSV and PI3V infections on selected immune responses in their offspring was examined. Blood samples were collected weekly for 12 weeks from six newborn calves from each of vaccinated (experimental) and unvaccinated (control) dams. Specific antibodies to M. haemolytica, BRSV and PI3V and mean values of IgA, IgG concentrations were significantly higher in the experimental calves compared with the controls. However, specific antibody titres to adenovirus type 3, BHV1 and BVDV in the experimental calves had constant levels while the control group levels changed. The IgM, Hp and SAA concentrations generally increased until week 8 in the experimental group, but the control group titres became higher after week 9. This study demonstrates that specific immunisation of cows pre-partum significantly stimulated parameters associated with immunity and it also controlled the acute phase response intensity in their offspring. Therefore the vaccination of dams may provide additional antibody protection against infection to their offspring.

Effect of steroidal and non-steroidal anti-inflammatory drugs on inflammatory markers in calves with experimentally-induced bronchopneumonia.

The influence of treatment with steroidal (SAIDs) and non-steroidal (NSAIDs) anti-inflammatory drugs on inflammatory markers in thirty, 6-8 week old calves with induced bronchopneumonia was investigated. Animals received a single intravenous treatment with meloxicam (0.5 mg/kg body weight), flumethasone (0.05 mg/kg body weight) or sterile 0.9% NaCl (10 ml per animal). Body temperature, respiratory and heart rate, concentration of prostaglandins PGE2, PGF2alpha, thromboxane (TXB2), leukotriene (LTB4) and malonyldialdehyd (MDA) and proinflammatory cytokines i.e. tumor necrosis factor (TNFalpha) and interferon (INFalpha) were recorded in serum, bronchoalveolar lavage (BAL) and blood platelets (BP). A significant reduction of main inflammatory mediators PGE2, PGF2alpha,TXB2 and MDA after meloxicam treatment in calves with induced bronchopneumonia indicates a beneficial effect on the inflammatory processes. Contrary to effects observed by flumethasone, meloxicam induced an increase of LTB4 and INFalpha indicating that it is not immunosuppressive.

Effect of steroidal and non-steroidal anti-inflammatory drugs in combination with long-acting oxytetracycline on non-specific immunity of calves suffering from enzootic bronchopneumonia.

The aim of this paper was to compare the effect of flumethasone and meloxicam in combination with oxytetracycline on clinical and immunological parameters of calves suffering from enzootic bronchopneumonia. The study was performed on 30 Black-and-White Lowland Breed calves with clinical signs of enzootic bronchopneumonia divided randomly into three equal groups and, respectively, treated with-Group I: oxytetracycline and meloxicam; Group II: oxytetracycline and flumethasone; Group III (control): oxytetracycline only. Treatment of calves with the combination of oxytetracycline and meloxicam (Group I) caused a significantly faster, in comparison to other groups, improvement in the clinical illness index score (CIIS: cough, nasal discharge, dyspnea, depression and anorexia) and a faster normalization of body temperature. A slow decrease in white blood cell (WBC) count, the number of neutrophils, MID (mixed number of monocytes, eosinophils and basophils) and in the individual number of monocytes (CD14/CD45 positive cells) was observed in Groups I and III. In the blood of the calves which received oxytetracycline and flumethasone (Group II), leukocytosis, neutrophilia and monocytosis with concomitant lymphopenia and a low number of T cells (CD2+) was observed. Moreover, the calves treated with flumethasone exhibited a decrease in gamma-globulin concentration, and phagocytic parameters. Both drugs, flumethasone and meloxicam slightly decreased tumor necrosis factor (TNF) but meloxicam slightly increased the levels of interferon (IFN) in sera and in bronchoalveolar lavages (BALs). These results suggest that the combination of meloxicam with an antibiotic in calves suffering from enzootic bronchopneumonia is superior to the antibiotic alone and also to the combination of the antibiotic with flumethasone.