Chronic respiratory disease (CRD) caused by Mycoplasma gallisepticum (MG) leads to impaired broiler growth performance and significant economic losses worldwide. The utilization of essential oils (EOs) as natural alternatives to antibiotics to control CRD outbreaks is not completely clarified yet. Thus, we investigated the effect of a commercial EOs mixture (toldin CRD), in comparison to tilmicosin antibiotic, on the clinical observations, growth performance, immunity, digestive enzymes, gut barrier functions, and bacterial loads in broilers experimentally infected with MG. A total of 400 one-day-old broiler chicks were assigned into four groups; negative control (NC), positive control (PC), tilmicosin, and toldin CRD treated groups. All groups except NC were experimentally infected with MG at 14 d of age. Our data showed that birds treated with toldin CRD showed significant enhancement in the body weight gain (BWG) and feed conversion ratio (FCR) (P = 0.001 each) over the whole experimental period. Likely, improved digestibility and intestinal barrier functions in the toldin CRD treated group was evidenced by the significant upregulation (P < 0.05) of cholecystokinin ( CCK ), alpha 2A amylase ( AMY2A ), pancreatic lipase ( PNLIP ), junctional adhesion molecule-2 ( JAM-2 ), occludin, and mucin-2 ( MUC-2 ) genes. Moreover, toldin CRD exhibited immunostimulant and ant-inflammatory activities via significant downregulation (P < 0.05) of tumor necrosis factor-alpha ( TNF-α ) and interleukin ( IL )-6 genes, significant reduction of lysozyme (LYZ), myeloperoxidase (MPO), and nitric oxide (NO) levels (P = 0.03, 0.02, and 0.001, respectively) and significant increase in the immunoglobulin G (IgG) level (P = 0.03). Notably, immunohistochemistry and quantitative real-time polymerase chain reaction (qPCR) results showed prominent reductions (P < 0.05) in the levels of MG antigens and MG loads in the toldin CRD treated group, which were evidenced by relieving the clinical picture of MG experimental infection. In conclusion, we recommend the utilization of toldin CRD as a potential candidate for controlling MG infection in broiler chickens.

The present study aimed to assess the potential protective effects of cinnamon (Cinnamomum zeylanicum, Cin) and probiotic against CuSO₄-induced nephrotoxicity in broiler chickens. One-day-old Cobb chicks were assigned into seven groups (15 birds/group): control group, fed basal diet; Cin group, fed the basal diet mixed with Cin (200 mg/kg); PR group, receiving PR (1 g/4 L water); Cu group, fed the basal diets mixed with CuSO₄ (300 mg/kg); Cu + Cin group; Cu + PR group; and Cu + Cin + PR group. All treatments were given daily for 6 weeks. Treatment of Cu-intoxicated chickens with Cin and/or PR reduced (p < 0.05) Cu contents in renal tissues and serum levels of urea, creatinine, and uric acid compared to the Cu group. Moreover, Cin and PR treatment decreased lipid peroxidation and increased antioxidant enzyme activities in chickens’ kidney. Additionally, significant reduction (p < 0.05) in the mRNA expression of tumor necrosis factor alpha (TNF-α), interleukin (IL-2) and Bax, and in cyclooxygenase (COX-II) enzyme expression, and significant elevation (p < 0.05) in mRNA expression of IL-10 and Bcl-2 were observed in kidneys of Cu + Cin, Cu + PR, and Cu + Cin + PR groups compared to Cu group. Conclusively, Cin and/or PR afford considerable renal protection against Cu-induced nephrotoxicity in chickens.

This research aimed to assess the pharmacokinetics/pharmacodynamics (PK/PD) and tissue residues of spiramycin in chickens. The PK of spiramycin were determined in 12 chickens using a parallel study design in which each group of chickens (n = 6) received a single dose of spiramycin at 17 mg/kg intravenously (IV) or orally. Plasma samples were collected at assigned times for up to 48 h to measure spiramycin concentrations. Additionally, a tissue depletion study was performed in 42 chickens receiving spiramycin at 17 mg/kg/day orally for 7 days. The area under the plasma concentration–time curve values were 29.94 ± 4.74 and 23.11 ± 1.83 µg*h/mL after IV and oral administrations, respectively. The oral bioavailability was 77.18%. The computed withdrawal periods of spiramycin were 11, 10, and 7 days for liver, muscle, and skin and fat, respectively. The minimum inhibitory concentration for spiramycin against Mycoplasma synoviae (M. synoviae) strain 1853 was 0.0625 µg/mL. Using the PK/PD integration, the appropriate oral dose of spiramycin against M. synoviae was estimated to be 15.6 mg/kg. Thus, we recommend an oral dose of 15.6 mg spiramycin/kg against M. synoviae in chickens and a withdrawal period of 11 days following oral treatment with 17 mg spiramycin/kg/day for 7 days.

New, validated and accurate reversed phase HPLC method with UV detection has been established for simultaneous determination of a veterinary binary mixture of doxycycline hydrochloride (DOX) and tylosin tartrate (TYT). The stationary phase was ACE- 126-2546 AQ C-18 (250 × 4.6 mm i.d., 5 μm particle size) column at 25 °C, in an isocratic mode, using mobile phase containing a mixture of methanol: acetonitrile: distilled water in the ratio of 60:20:20 (v:v:v), with 0.01% trichloroacetic acid at the flow rate of 0.8 mL/min and UV detection was performed at 270 nm. The retention times were 4.02±0.01 and 5.62±0.01 mins for DOX and TYT, respectively. Selective determination of the cited veterinary drugs has been developed in their formulation. The method was found to be linear over 1-50 µg/mL for DOX and TYT with mean percentage recoveries 99.62±1.220 and 100.09±1.104%. The method was proven to be accurate, precise and specific. The obtained results were statistically compared with those of the official and reported methods; using Student’s t test, F test and one-way ANOVA, showing no significant difference with high accuracy. Specificity of the applied method was assessed by analysing the laboratory-prepared mixtures and their combined dosage form. The developed method was confirmed according to ICH guidelines. The validated method can be considered as alternative and basic method for the routine determination of this fixed dose combination with minimum sample preparation.

Coccidiosis, caused by the protozoan Eimeria, is a significant disease in poultry farms worldwide, leading to substantial economic losses. Triazines, benzene-aceto-nitrile derivatives, are widely employed in the field of veterinary healthcare to combat the hazardous impacts of protozoan parasite infestation comprising coccidiosis. The current research was designed to investigate the pharmacokinetic profile of diclazuril, a member of triazines, in Japanese quails (Coturnix japonica) and domestic pigeons (Columba livia) following single oral administration at 0.3 mg/kg body weight. 78 Quails (male: female, 1:1, 7 weeks old) and 78 pigeons (male: female, 1:1, 4 weeks old) were randomly divided into 13 groups for each species (n=6 birds/ group). Plasma samples were obtained at various time intervals (at time 0 [preceding diclazuril administration], and 0.5, 1, 4, 8, 12, 24, 48, 72, 96, 120, 144, and 168 hours after diclazuril administration) to determine its concentration utilizing high-performance liquid chromatography (HPLC). The non-compartmental approach was applied to assess the pharmacokinetic parameters via the aid of WinNonlin 8.3 software. In quails and pigeons, the peak plasma concentrations were 5.35 and 9.14 μg/mL attained at 8 hours, respectively. Additionally, the elimination half-lives (T1/2λz) were 30.74 and 26.48 hours, and the area under the plasma concentration-time curve from time zero to the last sample (AUC0-last) values were 155.67 and 343.57 μg h/mL, respectively. The mean residence time was 30.71 hours in quails and 39.68 hours in pigeons. Diclazuril exhibited favorable pharmacokinetic characteristics after oral administration at a dose of 0.3 mg/kg in quails and pigeons. However, to adjust the dosage regimen for curing coccidiosis, a future study is warranted to determine the clinical efficacy against coccidia infection. Moreover, further investigation is needed to evaluate the tissue residues and calculate the withdrawal time of diclazuril in quails and pigeons.