Diagnostic opportunities for evaluation of the exposure of dairy cows to the mycotoxins deoxynivalenol (DON) and zearalenone (ZEN): reliability of blood plasma,bile and follicular fluid as indicators

To investigate the usefulness of follicular fluid (FF) in relation to blood plasma and bile as indicators of exposure of dairy cows to ZEN, DON and their metabolites, a dose–response study was performed with 30 dairy cows. The cows, 10 in each group (named CON; FUS‐50, FUS‐100), received a diet with three different concentrations of Fusarium toxin‐contaminated maize. Thereby, the following dietary concentration were reached: CON (0.02 mg ZEN and 0.07 mg DON, per kg dry matter, DM), FUS‐50 (0.33 mg ZEN and 2.62 mg DON, per kg DM) and FUS‐100 (0.66 mg ZEN and 5.24 mg DON, per kg DM). ZEN, DON and de‐epoxy‐DON (de‐DON) were detected in FF. Based on the linear regression between toxin concentration in plasma and FF, it seems that about 50 % (m = 0.5) of ZEN present in plasma is present in FF while an increase of 1 ng/ml DON or de‐DON in plasma is paralleled by an increase of 1.5 ng/ml DON or 1.1 ng/ml de‐DON in FF. ZEN, DON and their metabolites, except zearalenone (ZAN), were also detected in bile. Contrary to DON and de‐DON, ZEN and its metabolites were accumulated in bile so that the concentration of ZEN and metabolites was much higher than for DON and de‐DON. The main compound was β‐zearalenol (β‐ZEL). The biliary ZEN, α‐zearalenol (α‐ZEL) and β‐ZEL concentration correlated linearly with each other with an uncertainty of <15 % (r² ≥ 0.86), whereas the ratio between ZEN: α‐ZEL: β‐ZEL was about 1.5:1:11. With the help of established linear relationship between toxin intake and toxin concentration, bile could be used as diagnostic indicator to assess the exposure of cows.     

Pharmacokinetic–pharmacodynamic relationship of marbofloxacin for Escherichia coli and Pasturella multocida following repeated intramuscular administration in goats

The pharmacokinetics (PK) and pharmacodynamics (PD) of marbofloxacin (MBF) were determined in six healthy female goats of age 1.00–1.25 years after repeated administration of MBF. The MBF was administered intramuscularly (IM) at 2 mg kg^?1 day^?1 for 5 days. Plasma concentrations of MBF were determined by high‐performance liquid chromatography, and PK parameters were obtained using noncompartmental analysis. The MBF concentrations peaked at 1 hr, and peak concentration (C_max) was 1.760 µg/ml on day 1 and 1.817 µg/ml on day 5. Repeated dosing of MBF caused no significant change in PK parameters except area under curve (AUC) between day 1 (AUC_0–∞D1 = 7.67 ± 0.719 µg × hr/ml) and day 5 (AUC_0‐∞D5 = 8.70 ± 0.857 µg × hr/ml). A slight difference in mean residence time between 1st and 5th day of administration and accumulation index (AI = 1.13 ± 0.017) suggested lack of drug accumulation following repeated IM administration up to 5 days. Minimum inhibitory concentration (MIC) demonstrated that Escherichia coli (MIC = 0.04 µg/ml) and Pasturella multocida (MIC = 0.05 µg/ml) were highly sensitive to MBF. Time‐kill kinetics demonstrated rapid and concentration‐dependent activity of MBF against these pathogens. PK/PD integration of data for E. coli and P. multocida, using efficacy indices: C_max/MIC and AUC_0–24hr/MIC, suggested that IM administration of MBF at a dose of 2 mg kg^?1 day^?1 is appropriate to treat infections caused by E. coli. However, a dose of 5 mg kg^?1 day^?1 is recommended to treat pneumonia caused by P. multocida in goats. The study indicated that MBF can be used repeatedly at dosage of 2 mg/kg in goats without risk of drug accumulation up to 5 days.     

Effects of long‐term in vitro exposure of ejaculated boar sperm to zearalenone and α‐zearalenol in sperm liquid storage medium

The effects of in vitro exposure of porcine spermatozoa to zearalenone (ZEN) and α‐zearalenol (α‐ZOL) were studied by evaluating several parameters of an in vitro fertilization (IVF) system. For this purpose, boar spermatozoa cultured with semen storage medium containing 0 (control), 10 and 1000 µg/L of ZEN and α‐ZOL for 1 week at 5°C were used for IVF of in vitro matured oocytes. Overall, there were no significant differences in the rates of total penetration, monospermic fertilization, and polyspermic fertilization of oocytes inseminated with spermatozoa from the different groups. Similarly, ZEN and α‐ZOL at 10 and 1000 µg/L did not have detrimental effects on the cleavage and development to blastocysts of oocytes after in vitro fertilization. Although the motility, viability, and plasma membrane integrity of spermatozoa significantly decreased after 3 weeks of storage compared to non‐stored spermatozoa (P < 0.05), ZEN and α‐ZOL at the evaluated concentrations did not exert detrimental effects on the above parameters, even after 3 weeks of storage. These results indicate that prolonged exposure of boar spermatozoa to ZEN and α‐ZOL up to 1000 µg/L under reduced metabolic conditions does not affect their in vitro function.     

Selenium supplementation improves nutrient intake and digestibility,and mitigates CH4 emissions from sheep grazed on the mixed pasture of alfalfa and tall fescue

Low selenium (Se) in soil and forage can adversely affect on the quality of animal-derived foods, and hence on human health. Lambs grazed on mixed pastures of alfalfa (Medicago sativa) and tall fescue (Festuca arundinacea) were supplemented with five levels of Se [0, 3, 6, 9 and 12 µg/kg body weight (BW)]. The intake of dry matter (DM) and organic matter (OM) varied with the level of Se supplementation, with a peak at 6 µg Se per kg BW (p ≤ 0.05). Gross energy (GE) intake, digestive energy (DE) intake and metabolic energy (ME) intake were higher at 6 µg Se per kg BW than at other Se levels (p < 0.01); in addition, methane energy (CH₄-E) output was lower at 6 µg Se per kg BW. Supplementation with Se significantly increased nitrogen (N) intake, faecal N and urine N, for which the peak values were 20.2 g N/, 5.62 g N/day and 7.92 g N/day, respectively, at 6 µg Se per kg BW. Se intake, blood Se, faecal Se, urine Se and retained Se were negatively correlated with forage crude protein (CP) content (p < 0.001) but were positively correlated with the content of neutral detergent fibre (NDF) (p < 0.001) and acid detergent fibre (ADF) (p < 0.001). Thus, we recommend the addition of 6 µg Se per kg BW to sheep grazed on pastures in regions with low soil Se.     

Evaluation of the protective effect of lycopene on growth performance,intestinal morphology,and digestive enzyme activities of aflatoxinB1 challenged broilers

The current study was conducted to investigate the protective efficiency of dietary lycopene (LYC) supplementation on growth performance, intestinal morphology, and digestive enzyme activities aflatoxinB₁ (AFB₁) challenged broilers. A total of 240 days old Arber across male broiler chicks were randomly allocated in five treatments and six replicates (eight birds per replicate); feed and water were provided ad libitum during the 42 days experiment. The treatment diets were as follows: (i) Basal diet (control), (ii) Basal diet + 100 µg/kg AFB₁ contaminated diet, (iii) Basal diet + 100 µg/kg AFB₁ + 100 mg/kg LYC1, (iv) Basal diet + 100 µg/kg AFB₁ + 200 mg/kg LYC2, and (v) Basal diet + 100 µg/kg AFB₁ + 400 mg/kg LYC3. The results showed that the addition of LYC to AFB₁ contaminated broiler diets significantly increased (p < .05) average daily gain (ADG) and decreased feed conversion ratio (FCR) compared to the AFB₁ diet. AFB₁ diet decreased the intestinal villus height (VH) and crypt depth ratio (VCR) while increasing the crypt depth (CD). However, dietary LYC supplemented diets relieved the intestinal morphological alterations. Dietary LYC supplementation (200 and 400 mg/kg) significantly improved (p < .05) intestinal digestive enzyme amylase and lipase activities with AFB₁ contaminated diet. These findings suggested that LYC is a promising feed supplement in the broiler industry, alleviating the harmful effects of AFB₁.     

Crocin supplementation during oocyte maturation enhances antioxidant defence and subsequent cleavage rate

The purpose of the present study was to assess the effect of crocin supplementation during oocyte maturation on the antioxidant defence and anti‐apoptotic ability and subsequent developmental competence of porcine oocytes. Oocytes were cultured in media containing 0, 300, 400 or 500 µg/ml of crocin. Upon maturation, the maturation rates, reactive oxygen species (ROS) and glutathione (GSH) levels, mRNA expression of genes (SOD, CAT, GPx, Bcl‐2, BAX and Caspase3), expression of cleaved caspase3 and subsequent embryo cleavage rates were measured. Results indicated that the maturation rate of the 400 µg/ml group was 86.80% (p < 0.01). The ROS concentration of the 500 µg/ml group was the lowest (p < 0.01). The GSH concentration of the 400 µg/ml group was the highest (p < 0.01). The SOD, CAT and GPx mRNA expression levels were the highest in the 300, 400 and 500 µg/ml groups, respectively, with the expression levels of all genes being significantly higher than that of the control group (p < 0.01). The Bcl‐2/BAX mRNA expression ratio in 400 and 500 µg/ml groups significantly higher than other groups and significantly decreased caspase3 expression level (p < 0.01). The expression level of cleaved caspase3 in the 500 µg/ml treatment group was the lowest, significantly lower than that of the control group (p < 0.01). The cleavage rate of the 400 µg/ml group was 62.50% (p < 0.01). These experimental results show that the supplementation of in vitro culture medium with 400 µg/ml of crocin significantly enhanced the antioxidant defence and anti‐apoptotic ability and subsequent cleavage rate of porcine embryo.     

Effect of supportive therapy on the pharmacokinetics of intravenous marbofloxacin in endotoxemic sheep

The purpose of this study was to determine the influences of supportive therapy (ST) on the pharmacokinetics (PK) of marbofloxacin in lipopolysaccharide (LPS)-induced endotoxemic sheep. Furthermore, minimum inhibitory concentration (MIC) of marbofloxacin against Escherichia coli, Mannheimia haemolytica, Pasteurella multocida, Klebsiella pneumoniae, Salmonella spp., and Staphylococcus aureus was determined. The study was performed using a three-period cross PK design following a 15-day washout period. In the first period, marbofloxacin (10 mg/kg) was administered by an intravenous (IV) injection. In the second and third periods, marbofloxacin was co-administered with ST (lactated ringer + 5% dextrose + 0.45% sodium chloride, IV, 20 ml/kg, dexamethasone 0.5 mg/kg, SC) and ST + LPS (E. coli O55:B5, 10 µg/kg), respectively. Plasma marbofloxacin concentration was measured using HPLC-UV. Following IV administration of marbofloxacin alone, the , AUC_0–∞, Cl_T, and V_dss were 2.87 hr, 34.73 hr × µg/ml, 0.29 L hr⁻¹ kg⁻¹, and 0.87 L/kg, respectively. While no change was found in the MBX + ST group in terms of the PK parameters of marbofloxacin, it was determined that the Cl_T of marbofloxacin decreased, AUC_0–∞ increased, and and MRT prolonged in the MBX + ST + LPS group. MIC values of marbofloxacin were 0.031 to >16 µg/ml for E. coli, 0.016 to >16 µg/ml for M. haemolytica, 0.016–1 µg/ml for P. multocida, 0.016–0.25 µg/ml for K. pneumoniae, 0.031–0.063 µg/ml for Salmonella spp., and 0.031–1 µg/ml for S. aureus. The study results show the necessity to make a dose adjustment of marbofloxacin following concomitant administration of ST in endotoxemic sheep. Also, the PK and pharmacodynamic effect of marbofloxacin needs to be determined in naturally infected septicemic sheep following concomitant administration of single and ST.     

The Mycobiota and Toxicity of Equine Feeds

Feed contamination can lead to nutrient losses and detrimental effects on animal health and production. The purposes of this study were to investigate the mycobiota in equine mixed feeds and to determine natural contamination with aflatoxin B₁ (AFB₁) and fumonisin B₁ (FB₁). Fungal enumeration of equine feed samples was done. A commercially available enzyme-linked immunosorbent assay kit was applied to quantify AFB₁ and FB₁. A comparison between ELISA and HPLC was carried out. Feed mould counts ranged from <1× 10² to 1× 10⁵ cfu/g. The most frequent genus isolated was Aspergillus (40.54%), followed by Penicillium (18.38%) and Fusarium (16.22%). The most prevalent Aspergillus sp. was A. flavus (36%). AFB₁ values ranged between 0.01 and 99.4 μg/kg. FB₁ levels ranged between 0.01 and 7.49 μg/kg. HPLC and ELISA methods showed positive correlation for AFB₁ and FB₁ determinations (r = 0.9851 and r = 0.9791, respectively). The ELISA analytical method was efficient for AFB₁ and FB₁ detection. The scarcity of studies on natural fungal contamination and on the presence of AFB₁ and FB₁ in materials used as equine feed ingredients highlights the value and contribution of this study.     

Effect of food on the pharmacokinetics of oral cefuroxime axetil in dogs

Cefuroxime axetil pharmacokinetic profile was investigated in 12 Beagle dogs after single intravenous and oral administration of tablets or suspension at a dose of 20 mg/kg, under both fasting and fed conditions. A three-period, three-treatment crossover study (IV, PO under fasting and fed condition) was applied. Blood samples were withdrawn at predetermined times over a 12-hr period. Cefuroxime plasma concentrations were determined by HPLC. Data were analyzed by compartmental analysis. No statistically significant differences were observed between formulations and feeding conditions on PK parameters. Independently of the feeding condition, absorption of cefuroxime axetil after tablet administration was low and erratic. The drug has been quantified in plasma in 3 out of 6 and 5 out of 6 dogs in the fasted and fed groups. For this formulation, the bioavailability (F), peak plasma concentration (C_max), and area under the concentration–time curve (AUC) of cefuroxime axetil were significantly enhanced (p < .05) by the concomitant ingestion of food (32.97 ± 13.47–14.08 ± 7.79%, 6.30 ± 2.62–2.74 ± 0.66 µg/ml, and 15.75 ± 3.98–7.82 ± 2.76 µg.hr/ml for F, C_max, and AUC in fed and fasted dogs, respectively), while for cefuroxime axetil suspension, feeding conditions affected only the rate of absorption, as reflected by the significantly shorter absorption half-life (T_½(a)) and time to peak concentration (T_max) (0.55 ± 0.27–1.15 ± 0.19 hr and 1.21 ± 0.22–1.70 ± 0.30 for T_½(a) and T_max in fed and fasted dogs, respectively). For cefuroxime axetil tablets, T > MIC (≤1 µg/ml) was <2 hr in fasted and ≈4 hr in fed animals, and for cefuroxime axetil suspension, T > MIC (≤1 µg/ml) was ≈5 hr and for T >MIC (≤4 µg/ml) was ≈2.5 hr for fasted and fed dogs, respectively. Cefuroxime axetil as a suspension formulation seems to be a better option than tablets. However, its short permanence in plasma could reduce its clinical usefulness in dogs.     

Effect of ketoprofen co-administration on pharmacokinetics of cefquinome following repeated administration in goats

The pharmacokinetics of cefquinome (2 mg/kg every 24 hr for 5 days) was determined following intramuscular administration alone and co-administration with ketoprofen (3 mg/kg every 24 hr for 5 days) in goats. Six goats were used for the study. In the study, the crossover pharmacokinetics design with 20-day washout period was performed in two periods. Plasma concentrations of cefquinome were assayed using high-performance liquid chromatography by ultraviolet detection. The mean terminal elimination half-life (t_1/2ʎz), area under the concentration–time curve (AUC_0–24), peak concentration (C_max), apparent volume of distribution (V_darea/F), and total body clearance (CL/F) of cefquinome after the administration alone were 4.85 hr, 11.06 hr*µg/ml, 2.37 µg/mL, 1.23 L/kg, and 0.17 L/h/kg after the first dose, and 5.88 hr, 17.01 hr*µg/mL, 3.04 µg/mL, 0.95 L/kg, and 0.11 L/h/kg after the last dose. Ketoprofen significantly prolonged t_1/2ʎz of cefquinome, increased AUC_0–24 and C_max, and decreased V_darea/F and CL/F. Cefquinome exhibited low accumulation after the administration alone and in combination with ketoprofen. These results indicated that ketoprofen prolonged the elimination of cefquinome in goats. The 24-hr dosing intervals at 2 mg/kg dose of cefquinome, which co-administered with ketoprofen, may maintain T> minimum inhibitory concentration (MIC) values above 40% in the treatment of infections caused by susceptible pathogens with the MIC value of ≤0.75 μg/ml in goats with an inflammatory condition.     

The acute phase response induced by Escherichia coli lipopolysaccharide modifies the pharmacokinetics and metabolism of florfenicol in rabbits

The aim of this study was to determine the effect of Escherichia coli lipopolysaccharide (LPS)‐induced acute phase response (APR) on the pharmaco‐kinetics and biotransformation of florfenicol (FFC) in rabbits. Six rabbits (3.0 ± 0.08 kg body weight (bw)) were distributed through a crossover design with 4 weeks of washout period. Pairs of rabbits similar in bw and sex were assigned to experimental groups: Group 1 (LPS) was treated with three intravenous doses of 1 μg/kg bw of E. coli LPS at intervals of 6 h, and Group 2 (control) was treated with an equivalent volume of saline solution (SS) at the same intervals and frequency of Group 1. At 24 h after the first injection of LPS or SS, an intravenous bolus of 20 mg/kg bw of FFC was administered. Blood samples were collected from the auricular vein before drug administration and at different times between 0.05 and 24.0 h after treatment. FFC and florfenicol‐amine (FFC‐a) were extracted from the plasma, and their concentrations were determined by high‐performance liquid chromatography. A noncompartmental pharmacokinetic model was used for data analysis, and data were compared using the paired Student t‐test. The mean values of AUC_0–∞ in the endotoxaemic rabbits (26.3 ± 2.7 μg·h/mL) were significantly higher (P < 0.05) than values observed in healthy rabbits (17.2 ± 0.97 μg·h/mL). The total mean plasma clearance (CL_T) decreased from 1228 ± 107.5 mL·h/kg in the control group to 806.4 ± 91.4 mL·h/kg in the LPS‐treated rabbits. A significant increase (P < 0.05) in the half‐life of elimination was observed in the endotoxaemic rabbits (5.59 ± 1.14 h) compared to the values observed in healthy animals (3.44 ± 0.57 h). In conclusion, the administration of repeated doses of 1 μg/kg E. coli LPS induced an APR in rabbits, producing significant modifications in plasma concentrations of FFC leading to increases in the AUC, terminal half‐life and mean residence time (MRT), but a significant decrease in CL_T of the drug. As a consequence of the APR induced by LPS, there was a reduction in the metabolic conversion of FFC to their metabolite FFC‐a in the liver, suggesting that the mediators released during the APR induced significant inhibitory effects on the hepatic drug‐metabolizing enzymes.     

Pharmacokinetics of tildipirosin in pig tonsils

The penetration of antimicrobials in pig tonsils is hardly known. The objective of the study was to quantify the tildipirosin (TD) penetration in tonsils. Animals were randomly divided into six groups (control, T1, T2 (1), T2(5), T2(10), and T2(15)) of eight animals. T1 and T2 groups received a dose of 2 and 4 mg of TD/kg bw in one shot (Zuprevo^® MSD Animal Health), respectively, and the control group received 2 mL of saline solution. The animals were sacrificed by intravenous administration of pentobarbital sodium 24 h after finishing the treatment for the control, T1, and T2(1) groups, whereas animals of T2(5), T2(10), and T2(15) groups were sacrificed at 5, 10, and 15 days, post‐treatment, respectively. Tonsils and blood samples were taken at necropsy to obtain plasma, and the tildipirosin concentration was determined by high‐performance liquid chromatography with tandem mass spectrometry detection. The concentration in plasma was always significantly lower than in tonsil. Average TD tonsil concentrations increased significantly in a dose‐dependent manner, and the tonsil TD vs. plasma TD concentration ratio was approximately 75 for the doses of 2 and 4 mg of TD/kg bw at 24 h post‐treatment. Moreover, the maximum concentration of tildipirosin in tonsil was observed at 1 day postadministration, and this concentration decreased gradually from this day until 15 days postadministration for the dose of 4 mg of TD/kg bw. Finally, the ratio AUC_tonsil/AUC_plasma was 97.9, and the T_{1/2 (h)} was clearly higher in tonsil than in plasma.     

Pharmacokinetics and relative bioavailability of meloxicam oil suspension in pigs after intramuscular administration

This study aimed to develop one novel meloxicam (MEL) oil suspension for sustained-release and compare the pharmacokinetic characteristics of it with MEL conventional formulation in pigs after a single intramuscular administration. Six healthy pigs were used for the study by a crossover design in two periods with a withdrawal interval of 14 days. Plasma concentrations of MEL were measured by ultra-performance liquid chromatography–tandem mass spectrometry (UPLC-MS/MS). Pharmacokinetic parameters were calculated by noncompartmental methods. The difference was statistically significant (p < .05) between MEL oil suspension and MEL conventional formulation in pharmacokinetic parameters of mean residence time (6.16 ± 4.04) hr versus (2.66 ± 0.55) hr, peak plasma concentration (C_max) (0.82 ± 0.12) µg/ml versus (1.12 ± 0.22) µg/ml, time needed to reach C_max (T_max) (2.33 ± 0.82) hr versus (0.59 ± 0.18) hr, and terminal elimination half-life (t_1/2λz) (3.74 ± 2.66) hr versus (1.55 ± 0.37) hr. The mean area under the concentration–time curve (AUC_0–∝) of MEL oil suspension and MEL conventional formulation was 5.35 and 3.43 hr µg/ml, respectively, with a relative bioavailability of 155.98%. Results of the present study demonstrated that the MEL oil suspension could prolong the effective time of drugs in blood, thereby reducing the frequency of administration on a course of treatment. Therefore, the novel MEL oil suspension seems to be of great value in veterinary clinical application.     

Clinical pharmacokinetics and outcomes of oral fluconazole therapy in dogs and cats with naturally occurring fungal disease

This multi-institutional study was designed to determine the clinical pharmacokinetics of fluconazole and outcomes in client-owned dogs (n = 37) and cats (n = 35) with fungal disease. Fluconazole serum concentrations were measured. Pharmacokinetic analysis was limited to animals at steady state (≥72 hr of treatment). The mean (range) body weight in 31 dogs was 25.6 (2.8–58.2) kg and in 31 cats was 3.9 (2.4–6.1) kg included in pharmacokinetic analyses. The dose, average steady-state serum concentrations (C_SS), and oral clearance in dogs were 14.2 (4.5–21.3) mg/kg/d, 26.8 (3.8–61.5) µg/mL, and 0.63 ml min⁻¹ kg⁻¹, respectively, and in cats were 18.6 (8.2–40.0) mg/kg/d, 32.1 (1.9–103.5) µg/mL, and 0.61 ml min⁻¹ kg⁻¹, respectively. Random inter-animal pharmacokinetic variability was high in both species. Two dogs had near twofold increases in serum fluconazole when generic formulations were changed, suggesting lack of bioequivalence. Median C_SS for dogs and cats achieving clinical remission was 19.4 and 35.8 µg/ml, respectively. Starting oral doses of 10 mg/kg q12h in dogs and 50–100 mg total daily dose in cats are recommended to achieve median C_SS associated with clinical remission. Due to the large pharmacokinetic variability, individualized dose adjustments based on C_SS (therapeutic drug monitoring) and treatment failure should be considered.     

Pharmacokinetics of thymoquinone in layer chickens following oral and intravenous administration

Thymoquinone (TQ) is the major constituent of Nigella sativa and known to possess a variety of pharmacological effects. This study was designed to evaluate the pharmacokinetic profile of TQ following oral (PO) and intravenous (IV) administration in layer chickens. The layer chickens were equally divided into two groups (six chickens in each group, total 12 chickens), and TQ was administered via PO and IV routes. For PO route, the dose was 20 mg/kg b.w. and for IV route, 5 mg/kg b.w. was administered, respectively. A sensitive and accurate High‐Performance Liquid Chromatography (HPLC) technique was validated for the quantification of TQ from plasma. The limit of detection (LOD) and limit of quantification (LOQ) were 0.02 µg/ml and 0.05 µg/ml, respectively with >80% recovery. Maximum plasma concentration (C_max) following PO and IV administration was 8.805 and 4.497 µg/ml, respectively, while time to reach at maximum concentration (T_max) was 1 and 0.1 hr, respectively. The elimination half‐lives were recorded as 1.02 and 0.978 hr, whereas the mean residence times were 1.79 and 1.036 hr following both PO and IV administration, respectively. The 85% PO bioavailability was indicative that TQ could be used for various therapeutic purposes in layer chickens.     

Antioxidant effects of supplementation of 3,4-dihydroxyphenyl glycol on sperm parameters and oxidative markers following cryopreservation in canine semen

Supplementing the extender with antioxidants with low molecular weight can enhance the quality of the post-thaw sperm during the freezing process. This study was aimed at determining the impacts of 3,4-dihydroxyphenyl glycol (DHPG) on the spermatozoa of the canine undergoing freeze-thawing process. In this study, 24 ejaculates were obtained from three mixed-breed dogs and were diluted in a Tris-based extender. The diluted semen was divided into aliquots for supplementation of 10, 30, 50 and 70 µg/ml of DHPG, control (without antioxidant) and control sham (DMSO). After being extended, the semen was equilibrated at a temperature of 4°C and then transferred to the straws and kept 4 cm above the liquid nitrogen for 20 min and was finally immersed in the liquid nitrogen. They were cryopreserved for seven days; then, sperm parameters including sperm motility evaluation, motility characteristics, viability, DNA and plasma membrane integrity, total antioxidant capacity (TAC), reduced glutathione content (GSH), antioxidant enzymes (superoxide dismutase [SOD], catalase [CAT] and glutathione peroxidase [GPx]) activity malondialdehyde (MDA) levels were evaluated. This study showed that spermatozoa cryopreservation with 50, 30 and 70 µg/ml of DHPG concentrations had better progressive motility, Curvilinear Velocity, Linearity, viability, intact plasma membrane and the levels of TAC, GPx and GSH were higher than the control group. The 50, 30 and 70 µg/ml of DHPG concentrations led to the significant decrease of DNA damage compared to the control group. Total motility, average path velocity, straight-line velocity and CAT activity were significantly improved in 30 and 50 µg/ml of DHPG concentrations, compared to the control group. Also, the 50 and 30 µg/ml of DHPG concentrations, decreased MDA levels compared to the other groups, significantly. In conclusion, our study showed that the addition 50 µg/ml of DHPG to the canine semen extender improved the semen characteristics and oxidative markers in the cryopreservation process.     

Protective effects of silymarin on fumonisin B1-induced hepatotoxicity in mice

The present study was conducted to investigate the effect of silymarin on experimental liver toxication induced by Fumonisin B₁ (FB₁) in BALB/c mice. The mice were divided into six groups (n = 15). Group 1 served as the control. Group 2 was the silymarin control (100 mg/kg by gavage). Groups 3 and 4 were treated with FB₁ (Group 3, 1.5 mg/kg FB₁, intraperitoneally; and Group 4, 4.5 mg/kg FB₁). Group 5 received FB₁ (1.5 mg/kg) and silymarin (100 mg/kg), and Group 6 was given a higher dose of FB₁ (4.5 mg/kg FB₁) with silymarin (100 mg/kg). Silymarin treatment significantly decreased (p < 0.0001) the apoptotic rate. FB₁ administration significantly increased (p < 0.0001) proliferating cell nuclear antigen and Ki-67 expression. Furthermore, FB₁ elevated the levels of caspase-8 and tumor necrosis factor-alpha mediators while silymarin significantly reduced (p < 0.0001) the expression of these factors. Vascular endothelial growth factor (VEGF) and fibroblast growth factor-2 (FGF-2) expressions were significantly elevated in Group 4 (p < 0.0001). Silymarin administration alleviated increased VEGF and FGF-2 expression levels (p < 0.0001). In conclusion, silymarin ameliorated toxic liver damage caused by FB₁ in BALB/c mice.     

Pharmacokinetics of florfenicol after intravenous administration in Escherichia coli lipopolysaccharide‐induced endotoxaemic sheep

Experiments in different animal species have shown that febrile conditions, induced by Escherichia coli lipopolysaccharide (LPS), may alter the pharmacokinetic properties of drugs. The objective was to study the effects of a LPS‐induced acute‐phase response (APR) model on plasma pharmacokinetics of florfenicol (FFC) after its intravenous administration in sheep. Six adult clinically healthy Suffolk Down sheep, 8 months old and 35.5 ± 2.2 kg in body weight (bw), were distributed through a crossover factorial 2 × 2 design, with 4 weeks of washout. Pairs of sheep similar in body weight were assigned to experimental groups: Group 1 (LPS) was treated with three intravenous doses of 1 μg/kg bw of E. coli LPS before FFC treatment. Group 2 (control) was treated with an equivalent volume of saline solution (SS) at similar intervals as LPS. At 24 h after the first injection of LPS or SS, an intravenous bolus of 20 mg/kg bw of FFC was administered. Blood samples (5 mL) were collected before drug administration and at different times between 0.05 and 48.0 h after treatment. FFC plasma concentrations were determined by liquid chromatography. A noncompartmental pharmacokinetic model was used for data analysis, and data were compared using a Mann–Whitney U‐test. The mean values of AUC_0–∞ in the endotoxaemic sheep (105.9 ± 14.3 μg·h/mL) were significantly higher (P < 0.05) than values observed in healthy sheep (78.4 ± 5.2 μg·h/mL). The total mean plasma clearance (CL_T) decreased from 257.7 ± 16.9 mL·h/kg in the control group to 198.2 ± 24.1 mL·h/kg in LPS‐treated sheep. A significant increase (P < 0.05) in the terminal half‐life was observed in the endotoxaemic sheep (16.9 ± 3.8 h) compared to the values observed in healthy sheep (10.4 ± 3.2 h). In conclusion, the APR induced by the intravenous administration of E. coli LPS in sheep produces higher plasma concentrations of FFC due to a decrease in the total body clearance of the drug.     

Effect of chelating and antioxidant agents on morphology and DNA methylation in freeze-drying rabbit (Oryctolagus cuniculus) spermatozoa

Freeze-drying (FD) has been exhaustively tried in several mammalian species as an alternative technique to sperm cryopreservation, but few studies have been done in rabbits (Oryctolagus cuniculus). The main objective of this study was to compare the protective effect of various antioxidants added to EDTA medium on structural and functional components of FD rabbit spermatozoa and on their status of global DNA methylation. FD media used were composed of basic FD medium (10 mM Tris-HCl buffer and 50 mM NaCl) supplemented with either 50 mM EDTA alone (EDTA) or added with 105 µM of rosmarinic acid (RA, EDTA-RA) or 10 µM of melatonin (MLT, EDTA-MLT). The effect of each medium on the preservation of FD spermatozoon structure was evaluated with light and scanning electron microscopy (SEM). Global DNA methylation was quantified in all FD sperm samples as well as in fresh spermatozoa. Morphologically, fracture points were evidenced in the neck, mid and principal piece of the spermatozoon tail. No differences in spermatozoon fracture points were evidenced among FD treatments: intact spermatozoa were the largest (p < .01) category, whereas the most frequent (p < .01) injury was the neck fracture, resulting in tailless heads. At SEM, the head of spermatozoa showed a well-conserved shape and intact membrane in all treatments. DNA methylation status was the same in all FD treatments. In conclusion, supplementation of EDTA, EDTA-RA and EDTA-MLT during FD preserved rabbit sperm morphological integrity and methylation status as well. Therefore, the difficulty of getting viable offspring using FD semen is likely unrelated to the impact of the lyophilization process on DNA methylation and morphology of lyophilized spermatozoa.     

Effects of enzymatically treated Artemisia annua L. on growth performance and some blood parameters of broilers exposed to heat stress

To evaluate the effects of enzymatically treated Artemisia annua L. (EA) on growth performance and some blood parameters of broilers exposed to heat stress (HS), 320 22‐day‐old Arbor Acres male broilers were randomly allotted into five groups with eight replicates of eight birds each. Broilers in the control group were housed at 22 ± 1°C and fed the basal diet. Broilers in the HS, HS‐EA_0.75, HS‐EA_1.00 and HS‐EA_1.25 groups were reared under HS (34 ± 1°C for 8 h/day and 22 ± 1°C for 16 h/day), and fed basal diet with 0, 0.75, 1.00 and 1.25 g/kg EA, respectively. The experiment ended at 42 days. Dietary 1.00 and 1.25 g/kg EA decreased blood pH and elevated body weight gain, feed intake and carcass yield compared to the HS group. Broilers fed EA diets had lower serum concentrations of malondialdehyde and corticosterone and activities of alanine aminotransferase and aspartate aminotransferase, and higher serum total superoxide dismutase activity, tri‐iodothyronine concentration and tri‐iodothyronine/thyroxine than the HS group. Serum catalase activity in HS‐EA_1.00 and HS‐EA_1.25 groups and activity to inhibit hydroxyl in the HS‐EA_1.00 group were higher than the HS group. In conclusion, dietary 0.75–1.25 g/kg EA addition alleviated HS induced impairments in broilers.