BACKGROUND: Although numerous reports support the beneficial effects of supplementing chromium (Cr) on broiler performance under normal and stress conditions, the optimal level has not been determined yet. OBJECTIVES: This study was conducted to investigate the effects of different levels of supplemental Cr on performance, cortisol, and thyroid hormones of broiler under normal and stress conditions. METHODS: A total of four hundred forty-eight broilers were used. Broilers allocated into 2×4 factorial experiment included: stress (normal and stress) and 4 levels of supplemental chromium (0, 1000, 2000, 3000 ppb) since day 18. A completely randomized design with 8 treatments and 4 replicates (14 birds per replicate) was used. Dexamethasone used as a stressor for one week (stress period, STP) then experiment continued to day 46 (recovery period, RCP). RESULTS: Feeding 1000 and 2000 ppb Cr improved feed conversion ratio (FCR) and increased T4 compared to 0 and 3000 ppb Cr in stressed broilers in STP (P<0.05). Feed intake (FI), body weight (BW) and T3 concentration were higher in broilers fed with 1000 ppb Cr in the diet and reared without stress in STP (P< 0.05). Despite the negative effect of stress on performance in RCP, dexamethasone-stressed broilers had better FCR. Feeding stressed birds with 1000 ppb Cr increased blood cortisol whereas it reduced cortisol in the normal-reared birds. CONCLUSIONS: The Dietary supplementation of 1000 and 2000 ppb Cr reduced deleterious effects of physiological stress. Moreover, 1000 ppb Cr improved FI and BW of broilers under normal condition at first week. Feeding high level of chromium under normal and stress conditions did not improve the performance.

Neutrophils were purified from blood of dexamethasone-treated (0.04 mg/kg of body weight) and untreated calves. Cells were untreated (controls) or cultured in media containing 5 or 10 ng of bovine recombinant granulocyte-macrophage colony-stimulating factor (rbGM-CSF)/ ml for 10 to 12 hours before being tested for various functions. Dexamethasone treatment of calves decreased luminol-dependent chemiluminescence, decreased phagocytosis of Pasteurella multocida and several Staphylococcus spp by various degrees, and decreased antibody-dependent cell-mediated cytotoxocity against bovine herpesvirus-infected cells by 26 to 32%. The percentage phagocytosis of coagulase-positive S aureus and S intermedius was higher than that of coagulase-negative S epidermidis for neutrophils from all calves. Culture of neutrophils with rbGM-CSF significantly increased (P < 0.05) all of the aforementioned functions, compared with control neutrophils; however, rbGM-CSF-induced increases in function tended to be higher in neutrophils from dexamethasone-treated calves than in neutrophils from untreated calves.

Introduction: Antimicrobial peptides (AMP) are a large group of innate immune effectors, which apart from antimicrobial activity show immunomodulative properties. Platelet-rich plasma (PRP) is a source of autologous growth factors and is used for stimulation of bone and soft tissue healing. The purpose of this study was to assess the influence of PRP and AMP extract on ovine monocyte-derived macrophage cultures. Material and Methods: The study was conducted on ovine macrophages (Mfs) previously stimulated with LPS or dexamethasone and then with preparations of PRP or AMP. Following activation of the Mfs their morphological and functional features were assessed. Results: The study revealed pro-inflammatory influence of both examined preparations on Mfs cultures on the basis of morphology, ROS generation and arginase activity. Both preparations enhanced the pro-inflammatory response of cultured Mfs. Conclusion: This activity may intensify the antimicrobial action of Mfs, however, in cases of excessive and prolonged inflammation the use of these preparations should be limited.

Piperlongumine (PL) is a bioactive alkaloid and medicinal compound of piperamide isolated from the long pepper (Piper longum Linn). It has demonstrated bactericidal action against Mycobacterium tuberculosis (MTB), the cause of pulmonary tuberculosis; nevertheless, immunomodulatory activity had not been identified for it in MTB-triggered granulomatous inflammation. This study investigated if piperlongumine could inhibit such inflammation. Mycobacterium tuberculosis strain H37Rv was subjected to a broth microdilution assay. Piperlongumine at 5, 15, and 25 μg/mL, 0.2% dimethyl sulphoxide as control or 4 μM of dexamethasone were tested in vitro on MH-S murine alveolar macrophages. BALB/c mice were orally administered PL at 50, 100 and 150 mg/kg b.w. after trehalose-6,6-dimycolate (TDM) stimulation. Chemokine and cytokine concentrations were determined in lung supernatants. Flow cytometry and Western blot analysis were performed to determine phosphorylated spleen tyrosine kinase (Syk), c-Jun N-terminal kinase (JNK) and extracellular signal-regulated kinase (ERK) pathways. Piperlongumine inhibited inflammatory mediators and adherence of lymphocyte function-associated antigen 1 to MH-S cells following TDM activation. It also improved macrophage clearance of MTB. In TDM-stimulated MH-S cells, PL significantly influenced the macrophage inducible Ca²⁺-dependent lectin receptor (Mincle)-Syk-ERK signalling pathway. Oral dosing of PL effectively suppressed the development of pulmonary granulomas and inflammatory reactions in the TDM-elicited mouse granuloma model. PL as an inhibitor of MTB-triggered granulomatous inflammation may be an effective complementary treatment for mycobacterial infection.

Introduction: Due to the high heterogeneity of canine lymphoma, the aim of the present study was to test in vitro the chemosensitivity of canine high-grade primary lymphoma cells to various cytostatic drugs commonly used to treat dogs: 4-HO-cyclophosphamide, doxorubicin, dexamethasone, prednisolone, vincristine, etoposide, chlorambucil, lomustine, and cytosine arabinoside. Material and Methods: To determine the cell viability and drug ability to induce apoptosis two different tests were used: an MTT assay and annexin V/propidium iodide staining. Results: Both in vitro tests were found to be useful tools. Significant differences in the sensitivity, depending on the drug type, between B-, T- and mixed/null-type lymphoma cells were found for the majority of the tested drugs. B-type cells were the most sensitive in vitro, whereas T-type cells seemed to be the most resistant. Doxorubicin, chlorambucil, etoposide, and vincristine most strongly reduced the cell viability and induced apoptosis. Conclusion: In vitro assays, such as the MTT test and especially the annexin V/PI assay, may be useful tools for predicting a response to the treatment of high-grade lymphoma in dogs or improving the treatment outcomes in individual animals.

Objective: The objective of this study was to investigate the efficacy of newly developed multi¬component ear drops for the treatment of otitis caused by parasites, bacteria, and fungi in dogs, cats, ferrets, fancy rabbits, and foxes. Materials and Methods: A new drug for veterinary use was developed that contained levofloxacin hemihydrate (0.3%), clotrimazole (0.1%), dexamethasone sodium phosphate (0.1%), and mox¬idectin (0.01%). In the initial stage of otoacariasis (or the ear form of psoroptic scab), the drug was used twice with an interval of 57 days. When otoacariasis (psoroptic scab) was complicated by otitis of bacterial and/or fungal etiology, the drug was used as follows: instilled once a day, within 1014 days in the ear canal for 25 drops of the drug. The study of therapeutic efficacy was per¬formed on cats, dogs, ferrets, foxes, and fancy rabbits with ear pathology. Results: The recovery of cats, ferrets, dogs, and foxes after the double use of ear drops during otoacariasis was established. In the ear form of psoroptic scab in fancy rabbits after treatment, Psoroptes cuniculi mites were not detected. The specific (antimicrobial and antifungal) activity of the drug was confirmed in vivo using the following scheme of drug use: the drug was instilled once a day, within 1014 days in the ear canal, 25 drops of the drug in animals with external otitis and otitis media. Conclusion: The rational combination of active components developed in this study is effective and safe for use in animals with microbial diseases of the ears. [J Adv Vet Anim Res 2020; 7(1.000): 115-126]

This case was carried out to compare the healing process and time for the treatment of mange in goats using a combination of Ivermectin with dexamethasone to the earlier Ivermectin with antihistaminics approach. A 3 ½ years old female Boer cross goat was presented with a complaint of crusty lesions on different parts of the body during a routine farm visit in Selangor, Malaysia. Microscopic examinations of the skin scrapes taken revealed Sarcoptes and Psoroptes sp. of mites, while hematological analysis showed slight leucocytosis, neutrophilia with left shift, monocytosis, hyperproteinemia and hyperglobulinemia. Ivermectin injection at 0.2 mg/kg subcutaneously was administered once every 2 weeks in 4 divided doses, while Dexamethasone injection at 1 mg/10 kg and multivitamin at 10 mg/kg IM for 5 days repeated at alternate weeks. Significant improvement was recorded 6 weeks after commencement of treatment and full recovery at 10 weeks. The current drug regimen proved more effective when compared with previous cases that were treated with a combination of ivermectin and antihistaminics.

Objective: The objective of this investigation was to determine the effects of dexamethasone (DEX) on the weight and cellularity of abdominal and subcutaneous fat depots. Materials and Methods: The study was conducted on four broiler chicks (20 chicks per group) fed commercial feed and water ad libitum. The DEX was supplied with feed at 0 mg/kg (non-DEX), 3 mg/kg (DEX-1), 5 mg/kg (DEX-2), and 7 mg/kg (DEX-3) from day 0 to day 28. The entire abdominal and subcutaneous fat depots were collected and weighed after sacrificing five birds from each group on days 14 and 28. Results: The DEX groups had considerably lower (p < 0.05) fat depot weights with dose-related variation noted among the DEX groups. The histological findings revealed the presence of uniloc¬ular, round to oval-shaped adipocytes. The DEX-1 and DEX-2 had way lower (p < 0.05) numbers of adipocytes while the DEX-3 had considerably higher (p < 0.05) numbers of adipocytes than the non-DEX. DEX-1 and DEX-2 had larger (p < 0.05) adipocytes whereas DEX-3 had smaller adipocytes than the non-DEX. Adipocyte sizes and fat depot weights were found to have very strong negative relationships. Conclusion: Dietary DEX affects the growth and distribution of abdominal and subcutaneous fat depots and adipocyte cellularity subjected to both dose and duration of DEX treatment. [J Adv Vet Anim Res 2022; 9(4.000): 583-590]

This study investigated dexamethasone (DXM) residues in the milk from intramuscularly dosed dairy cows and established the withdrawal time (WT) of DXM in milk. Eighteen healthy Holstein cows were injected with 20 (DXM-1) or 40 mL (DXM-2) of a drug containing 1 mg/mL of DXM. After administering DXM, milk samples were collected from all cows at 12-hour intervals for five days. The DXM residue concentrations in milk were determined by liquid chromatography-tandem mass spectrometry. The correlation coefficient of the calibration curve was 0.9966, and the limits of detection and quantification (LOQ) were 0.03 and 0.1 μg/kg, respectively. The recoveries were 97.0% to 104.0%, and the coefficient of variations was less than 7.22%. After treatment, DXM in DXM-1 was detected above the LOQ in two milk samples at 36 hours and below the LOQ in all milk samples of DXM-2 at 48 hours. Using the WT calculation program WT 1.4, the withdrawal periods of DXM-1 and DXM-2 in milk were established to be two days. In conclusion, the developed analytical method is sensitive and reliable for detecting DXM in milk. The estimated WT of DXM in bovine milk is shorter than the current milk WT recommendation of three days for DXM in lactating dairy cows.