A Wake-Up Call: Determination of Antibiotics Residue Level in Raw Meat in Abattoir and Selected Slaughterhouses in Five Local Government in Kano State, Nigeria.

The frequent use of antibiotics may result in drug residues that can be discovered at varying quantities in animal products such as milk or meat. The presence of pharmaceutical residues in food above the MRLs has been perceived globally by various persons. Antibiotics residues are present in food, which can endanger human health by causing antibiotic sensitivity, allergic reactions, microflora imbalance, bacterial resistance to antibiotics in microorganisms, and financial loss to the food industry. Farmers around the world utilize them on a sporadic basis for both preventative and curative purposes. This study assessed the antibiotics residues in raw meat sold in 6 slaughter houses in Kano States. The study is a descriptive cross-sectional study involving six (6) major slaughter house in Kano state. Muscle, Kidney and liver samples were collected from each slaughterhouse. The antibiotic residues in the meat samples were analysed using high performance liquid chromatography (HPLC) for tetracycline, ciprofloxacin and oxytetracycline residue results were presented in charts and tables. Out of a total of 18 beef samples analyzed during this study, 15 (83%) of the total samples had detectable levels of tetracycline residues from which 6(33.3%) had tetracycline residues at violative levels above the WHO/FAO maximum residue limits (MRLs), out of those 18 beef samples analyzed during this study, 6(33%) of the total samples had detectable levels of oxytetracycline residues from which 3(17%) had oxytetracycline residues at violative levels above the WHO/FAO maximum residue limits (MRLs) and out of those 18 beef samples analyzed during this study, 12(67%) of the total samples had detectable levels of ciprofloxacin, all levels are below the WHO/FAO maximum residue limits (MRLs). This high level of tetracycline and oxytetracycline residues in greater proportion of meat destined for human consumption at violative levels could be as a result of the indiscriminate use and misuse of veterinary drugs as commonly practiced among livestock producers and marketers without observing withdrawal period prior to slaughter. These results indicate that consumers may be predisposed to health hazards and hinder international meat trade from Nigeria. Regulatory authorities should therefore ensure compliance with good agricultural practices including withdrawal period of drugs used for treatment of food animals.

Judicious and non-judicious use of colistin sulfate in indoor poultry experimentation and its effect on haematological parameters and body weight in broiler

The aim of this study was to evaluate the effects of discriminate and indiscriminate use of colistin sulfate on body weight and haematological parameters in broiler. Day-old-broiler chicks were collected and reared for up to 31 days. The chicks were randomly divided into control, discriminate and indiscriminate antibiotic group. The discriminate group was treated with colistin sulfate antibiotic (Eskolis-24) for one week (from 16th to 22th day) followed by one week withdrawal period. In case of indiscriminate group, the poultry were treated with colistin sulfate antibiotic for 14 days (from 16th to 29th day) without any withdrawal period until sacrifice. The body weight of the birds were recorded daily. The mean body weight was highest in indiscriminate group (1408.22±133.49 gm) followed by discriminate group (1330.15±134.93 gm) and control group (1243.81±173.19 gm). The differences among means of three groups were not statistically significant. The Total erythrocyte count (Million/mm3) of control, discriminate, and indiscriminate groups were 2.53± 0.05, 2.56±0.08, and 2.52±0.08 respectively. The hemoglobin (gm%) were 7.06± 0.09, 7.03± 0.12, and 7.11±0.09 respectively and the Packed Cell Volume (%) were 19.66±1.11, 19.33±0.95, and 20.16±0.70 respectively. The results found were not statistically significant among the groups for TEC, Hb and PCV respectively. Total lymphocyte (%) count were 67.16±0.60, 70±1.15, and 71.83±1.30 respectively. Total neutrophil (%) count were 32.83± 0.60, 28.83±1.42, and 26.83±1.10 respectively. Total eosinophil (%) count were 0± 0, 1±0.44, and 1.16±0.40 respectively. Total basophil (%) count were zero (0) and total monocyte (%) count were 0± 0, 0.17±0.17, and 0.17±0.17 respectively. In our experiment, both discriminate and indiscriminate groups showed no significant differences of lymphocyte, neutrophil, eosinophil, basophil and monocyte. Therefore, discriminate and indiscriminate use of colistin sulfate for two weeks has no effect on haematological parameters of broiler poultry. Further experiment needed for more concise conclusion. Asian Australas. J. Food Saf. Secur. 2021, 5 (2), 43-54

A Behavioural Analysis of Serotonergic Functional Status Following MDMA Exposure

<p>Rationale +/- 3,4-Methylenedioxymethamphetamine (MDMA) produces effects on a number of neurochemical systems. Many studies have shown that repeated MDMA administration produces deficits in central serotonergic neurotransmission, which have been suggested to underlie some of the behavioural changes associated with use. Objectives The present studies sought to evaluate the functional statuses of the serotonin transporter (SERT) and the serotonin2c (5-HT2c) and serotonin2a (5-HT2a) receptors following treatment with MDMA to determine whether behavioural deficits could be attributed to alterations in these proteins. Methods Rats received a pretreatment regimen of MDMA (4 x 10mg/kg MDMA injections administered at 2h intervals) or the saline vehicle and, 2 weeks later, [3H] paroxetine binding was undertaken to assess densities of SERT. In other groups, dose-effect curves for MDMA-produced hyperactivity were determined. Additional groups were tested following a 12-week withdrawal period from MDMA in order to assess whether there was recovery of function. The functional status of the SERT was further examined by determining the effect of MDMA pretreatment on the reduction in MDMA-produced hyperactivity (0.0 - 10.0mg/kg) produced by the selective serotonin reuptake inhibitor, clomipramine (0.0 - 5.0mg/kg). The ability for the 5-HT2c receptor agonist, m-CPP (0.0 - 2.5mg/kg) to produce hypolocomotion or increased emergence latency or for the 5-HT2a receptor agonist, DOI (0.0 - 2.0mg/kg) to produce wetdog shakes (WDS) were examined in MDMA pretreated rats. The ability for the 5-HT2c receptors to modulate MDMA-produced hyperactivity was assessed by examining the effect of MDMA pretreatment on the potentiation of MDMA-produced hyperactivity produced by the selective antagonist, RS102221 (0.0 - 1.0mg/kg). Conversely, the modulatory abilities of the 5-HT2a receptors were assessed by examining the effect of MDMA pretreatment on the attenuation of MDMA-produced hyperactivity produced by the antagonist, ritanserin (0.0 - 10.0mg/kg). Results MDMA pretreatment produced widespread reductions in SERT binding densities 2 weeks following administration. Prior exposure to MDMA rendered rats tolerant to MDMA-produced hyperactivity when tested 2, but not 12, weeks following MDMA administration. Two weeks following MDMA pretreatment rats were also less responsive to the clomipramine-produced attenuation of MDMA-produced hyperactivity. MDMA pretreatment failed to alter M-CPP -produced hypolocomotion or increased emergence latency, but decreased the ability for DOI to induce WDS. Further, MDMA pretreated rats exhibited tolerance to RS102221 as shown by a rightward shift in the dose effect curve and complete tolerance to ritanserin. Conclusions Following MDMA pretreatment, the decreased SERT binding densities and inability of clomipramine to attenuate MDMA-produced effects might explain tolerance to the locomotor activating effects produced by MDMA. Functional recovery also occurred with extended abstinence from the drug, suggesting that MDMA produced transient serotonergic alterations. The results support the idea that the 5-HT2a and 5-HT2c receptors that modulate MDMA-produced hyperactivity are functionally distinct from the receptors that mediate m-CPP- and DOI-induced behavioural responses, as m-CPP-produced behaviours were resilient, yet RS102221-induced effects were reduced, by MDMA pretreatment. RS102221 is highly selective in comparison to ritanserin, yet there was only one dose that produced significant potentiation of MDMA-produced hyperactivity, whereas there were several effective ritanserin doses. This suggests that the 5-HT2a receptors had a greater role in modulating MDMA-produced hyperactivity. Additionally, 5-HT2a receptors might be more susceptible to MDMA-induced desensitisation than 5-HT2c receptors, as MDMA pretreated rats exhibited some tolerance to the potentiating effects of RS102221 but were unresponsive to any ritanserin dose. In conclusion, MDMA-induced locomotor tolerance was attributable to decreased SERT densities and function as well as desensitisation of 5-HT2a receptors that facilitate hyperactivity.</p>

A Behavioural Analysis of Serotonergic Functional Status Following MDMA Exposure

<p>Rationale +/- 3,4-Methylenedioxymethamphetamine (MDMA) produces effects on a number of neurochemical systems. Many studies have shown that repeated MDMA administration produces deficits in central serotonergic neurotransmission, which have been suggested to underlie some of the behavioural changes associated with use. Objectives The present studies sought to evaluate the functional statuses of the serotonin transporter (SERT) and the serotonin2c (5-HT2c) and serotonin2a (5-HT2a) receptors following treatment with MDMA to determine whether behavioural deficits could be attributed to alterations in these proteins. Methods Rats received a pretreatment regimen of MDMA (4 x 10mg/kg MDMA injections administered at 2h intervals) or the saline vehicle and, 2 weeks later, [3H] paroxetine binding was undertaken to assess densities of SERT. In other groups, dose-effect curves for MDMA-produced hyperactivity were determined. Additional groups were tested following a 12-week withdrawal period from MDMA in order to assess whether there was recovery of function. The functional status of the SERT was further examined by determining the effect of MDMA pretreatment on the reduction in MDMA-produced hyperactivity (0.0 - 10.0mg/kg) produced by the selective serotonin reuptake inhibitor, clomipramine (0.0 - 5.0mg/kg). The ability for the 5-HT2c receptor agonist, m-CPP (0.0 - 2.5mg/kg) to produce hypolocomotion or increased emergence latency or for the 5-HT2a receptor agonist, DOI (0.0 - 2.0mg/kg) to produce wetdog shakes (WDS) were examined in MDMA pretreated rats. The ability for the 5-HT2c receptors to modulate MDMA-produced hyperactivity was assessed by examining the effect of MDMA pretreatment on the potentiation of MDMA-produced hyperactivity produced by the selective antagonist, RS102221 (0.0 - 1.0mg/kg). Conversely, the modulatory abilities of the 5-HT2a receptors were assessed by examining the effect of MDMA pretreatment on the attenuation of MDMA-produced hyperactivity produced by the antagonist, ritanserin (0.0 - 10.0mg/kg). Results MDMA pretreatment produced widespread reductions in SERT binding densities 2 weeks following administration. Prior exposure to MDMA rendered rats tolerant to MDMA-produced hyperactivity when tested 2, but not 12, weeks following MDMA administration. Two weeks following MDMA pretreatment rats were also less responsive to the clomipramine-produced attenuation of MDMA-produced hyperactivity. MDMA pretreatment failed to alter M-CPP -produced hypolocomotion or increased emergence latency, but decreased the ability for DOI to induce WDS. Further, MDMA pretreated rats exhibited tolerance to RS102221 as shown by a rightward shift in the dose effect curve and complete tolerance to ritanserin. Conclusions Following MDMA pretreatment, the decreased SERT binding densities and inability of clomipramine to attenuate MDMA-produced effects might explain tolerance to the locomotor activating effects produced by MDMA. Functional recovery also occurred with extended abstinence from the drug, suggesting that MDMA produced transient serotonergic alterations. The results support the idea that the 5-HT2a and 5-HT2c receptors that modulate MDMA-produced hyperactivity are functionally distinct from the receptors that mediate m-CPP- and DOI-induced behavioural responses, as m-CPP-produced behaviours were resilient, yet RS102221-induced effects were reduced, by MDMA pretreatment. RS102221 is highly selective in comparison to ritanserin, yet there was only one dose that produced significant potentiation of MDMA-produced hyperactivity, whereas there were several effective ritanserin doses. This suggests that the 5-HT2a receptors had a greater role in modulating MDMA-produced hyperactivity. Additionally, 5-HT2a receptors might be more susceptible to MDMA-induced desensitisation than 5-HT2c receptors, as MDMA pretreated rats exhibited some tolerance to the potentiating effects of RS102221 but were unresponsive to any ritanserin dose. In conclusion, MDMA-induced locomotor tolerance was attributable to decreased SERT densities and function as well as desensitisation of 5-HT2a receptors that facilitate hyperactivity.</p>

Interaction Between Florfenicol and Doxycycline Involving Cytochrome P450 3A in Goats (Capra hricus)

When two drugs are combined, drug-drug interactions (DDI) often occur. Metabolic DDI usually occur due to inhibition of the metabolism of one drug by the other. This leads to an increase in the plasma concentration of the drug whose metabolism is inhibited. The objective of this research study was to verify the DDI risk of two antibacterial, florfenicol (FF) and doxycycline (DOX) due to metabolism. Because food containing residues of any pharmacologically active substance could potentially constitute a public health hazard, we selected a food producing animal, goat, goat liver microsomes and recombinant metabolic enzymes, for in vivo and in vitro metabolism studies. In vitro experiments showed that CYP3A was the key enzyme subfamily in FF metabolism, DOX slowed down FF metabolism and R440 was possibly the key amino acid in the metabolic interaction between FF and DOX. In vivo studies in the goats showed that DOX inhibited up-regulation of CYP3A24 gene expression produced by FF; in liver and kidney, DOX slightly slowed down FF metabolism. Quantitative prediction of DDI risk suggest that when DOX is used in combination with FF in veterinary medicine, may result in a clinical significant increase of FF plasma and tissue concentrations, resulting a prevalence of harmful tissue residues of medicinal products in the food chain. Through our experimentation, when DOX is used in combination with FF, the withdrawal period of FF in the kidney was extended by 1 day. Otherwise, an appropriate withdrawal period (20 days) of FF was established for FF and DOX combined use to ensure that the animal can be safely slaughtered for food.

ANTIMICROBIALS USE IN BROILER CHICKEN BREEDING: CASE OF THE AIN DEFLA PROVINCE (ALGERIA)

The objective of this study is to assess the use of antimicrobials in the broiler production in Algeria, through a survey completed by private veterinarians of the Ain Defla province. In this context, 65 band breeding were studied for antimicrobial use between October 2019 and June 2020. The results showed that all of the studied bands received antimicrobial treatments for at least 5 days during the breeding period. Quinolones class was the most widely used class of antimicrobials (24.4%), followed by the tetracyclines class (22.5%), sulfonamides (20.1%) and polypeptides (12.1%). Macrolides and beta-lactams come last (4.02% and 3.22% respectively). 160 mg of active compound were administered per kg of chicken meat produced. The number of daily doses (nDDkg) was 10.5, while the treated live weight (nCDkg) was 2.66. Per molecule, chickens were more exposed to colistin, doxycycline, oxytetracycline and enrofloxacin. The withdrawal period of used bands was not respected, and meat from these treated broilers was found to contain antimicrobial residues at 33.9%. The reasons for this frequent use are various: poor conditions and bad practices of breeding, poor quality of day-old chicks, veterinary practices, and difficulties of control by veterinary authorities.

Influence of air supply on coal spontaneous combustion during support withdrawal in fully mechanized coal mining and its prevention

It is necessary to change the air supply rate of the working face during the withdrawal of fully mechanized mining, making it important to study the oxidation characteristics of coal samples under different air supply rates. Through a self-made temperature-programmed experimental device, our focus was on studying the change laws of indicator gases released during the low-temperature (303.15–473.15 K) oxidation stage when the air supply rates of the coal samples were 0.67, 1.33, 2, 2.67, and 3.33 mL/s. The experimental results showed that the air supply increased, the concentrations of CO, C2H6, C3H8, C2H4, and C2H2 generated by the coal sample at the same temperature decreased, and the oxidation process decelerated. The initial temperatures of the four hydrocarbon gases were delayed to varying degrees with the increase in the air volume, and C2H4 was found to be more suitable as a hydrocarbon gas for the early warning of coal spontaneous combustion. Surface fitting was applied to analyze the change law of the CO generation rate under the combined effect of temperature and air supply; the change was divided into three stages. The CO concentration model at the upper corner of the working face during the withdrawal period was deduced, and comprehensive safety measures were put forward to prevent coal spontaneous combustion during the withdrawal period.

Pharmacokinetic/Pharmacodynamic Modeling of Spiramycin against Mycoplasma synoviae 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.

Standardization of Dose and Delivery of Oxytetracycline against Streptococcus agalactiae Infection in Genetically Improved Farmed Tilapia (GIFT)

Background: Tilapia (Oreochromis niloticus) is one of the most important aquaculture species in India. Streptococcus agalactiae is a highly debilitating pathogen of farmed tilapia. In this study, oxytetracycline (OTC) dose and delivery were standardized against S. agalactiae infection in genetically improved farmed tilapia (GIFT) and pharmacokinetics after oral administration was evaluated. Methods: LD50 value of S. agalactiae was found to be 6.2×106 CFU/fish. Two methods of drug delivery were investigated at three different doses of 50, 70 and 90 mg/kg against the S. agalactiae infection. Pharmacokinetics of OTC was studied after per os administration of 100 mg/kg body weight per day and analysing the residues in kidney, liver and muscle at different time intervals. Result: Per os delivery of OTC 90 mg/kg controlled S. agalactiae infection and the withdrawal time of OTC to fall below MRL of 0.05 µg/g at 30°C was 21 days in kidney and liver and 14 days in muscle. The study indicated that the S. agalactiae infection in tilapia could be controlled by OTC and fish can be marketed after providing a withdrawal period of 14 days.