Saturday, 24 June 2017

Tetracycline resistance phenotypes and genotypes of coagulase-negative staphylococcal isolates from bubaline mastitis in Egypt

Research (Published online: 25-06-2017)
21. Tetracycline resistance phenotypes and genotypes of coagulase-negative staphylococcal 
isolates from bubaline mastitis in Egypt
K. A. Abd El-Razik, A. A. Arafa, R. H. Hedia and E. S. Ibrahim
Veterinary World, 10(6): 702-710
ABSTRACT
Aim: This study was devoted to elucidate the tetracycline resistance of coagulase-negative staphylococci (CNS) derived from normal and subclinical mastitic (SCM) buffaloes' milk in Egypt.
Materials and Methods: A total of 81 milk samples from 46 normal buffalo milk samples and 35 SCM buffalo milk samples at private dairy farms of Egypt were used in this study. CNS were identified using phenotypic and molecular methods (polymerase chain reaction [PCR]). CNS isolates were tested for tetracycline resistance using routine methods and multiplex PCR targeting tetracycline (tet) resistance genes followed by sequencing of positive PCR products and phylogenetic analysis.
Results: Isolation and identification of 28 (34.5%) CNS from normal and SCM buffaloes' milk, namely, Staphylococcus intermedius (39.2%), Staphylococcus xylosus (25.0%), Staphylococcus epidermidis (10.7%), Staphylococcus hominis (10.7%), and 3.5% to each of Staphylococcus sciuri, Staphylococcus hyicus, Staphylococcus lugdunensis, and Staphylococcus simulans. Using nested PCR, all the 28 CNS isolates revealed positive for 16srRNA gene specific for genus staphylococci and negative for thermonuclease (nuc) gene specific for Staphylococcus aureus species. The presence of tetracycline resistance-encoding genes (tetK, tetL, tetM, and tetO) was detected by multiplex PCR. All isolates were negative for tetL, M, and O genes while 14 (50%) CNS isolates were positive for tetK gene, namely, S. lugdunensis (100%), S. hominis (100%), S. epidermidis (66.6%), S. intermedius(45.4%), and S. xylosus (42.8%). Nucleotide sequencing of tetK gene followed by phylogenetic analysis showed the high homology between our CNS isolates genes of tetracycline resistance with S. aureus isolates including Egyptian ones. This proves the transfer of the tetracycline resistance encoding genes between coagulase-negative and coagulase-positive Staphylococcus spp.
Conclusion: CNS isolates have distinguishingly high resistance to tetracycline. Abundant tetracycline usage for mastitis treatment leads to the spread of genetic resistance mechanisms inside CNS strains and among all Staphylococcus spp. Consequently, tetracycline is not effective anymore.
Keywords: buffaloes, coagulase-negative staphylococci, mastitis, tetracycline resistance, tetK gene.

Investigation of avian influenza infection in wild birds in Ismailia and Damietta cities, Egypt

Research (Published online: 25-06-2017)
20. Investigation of avian influenza infection in wild birds in Ismailia and Damietta cities, Egypt
Hanaa Mohamed Fadel and Rabab Afifi
Veterinary World, 10(6): 695-701
ABSTRACT
Aim: This study was carried out to monitor avian influenza (AI) infection in wild birds in Egypt.
Materials and Methods: A total of 135 wild birds were examined for the presence of H5, H7, and H9 hemagglutination inhibition antibodies. Organs and swab samples of 75 birds were screened by multiplex real-time reverse transcriptase-polymerase chain reaction (RRT-PCR) to detect AI subtypes H5, H7, and H9 matrix genes.
Results: The highest seropositive result was recorded in cattle egrets (90.9%) followed by crows (88.6%), semi-captive pigeons (44.8%), and moorhens (39.1%). In cattle egrets, semi-captive pigeons and moorhens, H5 antibodies predominated. In crows, H9 antibodies predominated. Multiple infections with two or three virus subtypes were highest in crows (6/39, 15.4%) followed by cattle egrets (3/30, 10%) and moorhens' (1/9, 11.1%) positive samples. Multiplex RRT-PCR results revealed two positive samples in cattle egrets and moorhens.
Conclusion: The results indicated high seropositive rates against AI virus subtypes H5 and H9 in the examined wild birds. Multiple infections with more than one AI virus (AIV) subtypes were detected in some birds. This requires a collaboration of efforts to monitor AIV infection in wild birds and implement suitable early intervention measures.
Keywords: avian influenza, hemagglutination inhibition, real-time reverse transcriptase-polymerase chain reaction, wild birds.

Epidemiological study of tick infestation in buffalo of various regions of district Khairpur, Pakistan

Research (Published online: 24-06-2017)
19. Epidemiological study of tick infestation in buffalo of various regions of district Khairpur, Pakistan
Farzana Abbasi, Imtiaz Hussain Raja Abbasi, Tahmeena Fakhur Nissa, Zohaib Ahmed Bhutto, Muhammed Asif Arain, Rab Nawaz Soomro, Farman Ali Siyal and Sarfraz Ali Fazlani
Veterinary World, 10(6): 688-694
doi: 10.14202/vetworld.2017.688-694

Abstract

Aim: The aim of this study was to determine the epidemiological infestation and identification of Ixodidae and Argasidae ticks species in buffalo of different parts of district Khairpur, Pakistan.

Materials and Methods: A total of 720 Water buffaloes from three tehsils (subdivisions) were selected randomly and examined from organized and unorganized dairy farms for tick infestation in district Khairpur, Pakistan. This epidemiological survey was conducted during April to September 2015.

Results: The overall mean population and preferred site of tick attachment to infested animals, in Gambat, Sobhodero, and Kot Diji tehsils, were observed on different body parts. The primary body area of infestation by ticks (head, thorax, abdomen, udder, and tail) ranged from highest in tail and udder part compared to lowest in the abdomen, head, and thorax. In all study areas, the infestation was higher (p<0.05) in tail and udder than other parts of the body. In all the study areas, the overall highest population was found in the month of July. In addition, we first time identify four new species of ticks (Hyalomma anatolicum, H. anatolicum excavatum, Hyalomma Ixodes excavatum, and Ixodes ricinus) in district Khairpur, Pakistan.

Conclusion: Results of this study provide additional information of epidemiological tick infestation, and will be helpful for evolving effective control policy for the management of tick infestation in study district.

Keywords: Argasidae, buffalo, identification, Ixodidae, population, prevalence, ticks, tick infestation.

Th1/Th2 balance and humoral immune response to potential antigens as early diagnostic method of equine Strongylus nematode infection

Research (Published online: 24-06-2017)
18. Th1/Th2 balance and humoral immune response to potential antigens as early diagnostic method of equine Strongylus nematode infection
Faten A. M. Abo-Aziza, Seham H. M. Hendawy, Amira H. El Namaky and Heba M. Ashry
Veterinary World, 10(6): 679-687

doi: 10.14202/vetworld.2017.679-687

Abstract

Aim: The aim of this study was to investigate the early diagnosis of strongyle infection based on early changes in Th1 and Th2 cytokines beside the diagnostic accuracy values and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and western blotting profiles using prepared strongyles antigens.

Materials and Methods: A total of 73 donkeys had a mean age of 4-32 years old were parasitologically examined for strongyle infection. The early changes in Th1 and Th2 cytokines were determined, and the diagnostic accuracy values and SDS-PAGE and western blotting profiles were performed using prepared strongyles antigens; crude somatic Strongylus vulgaris (CSS), excretory-secretory S. vulgaris (ESS), crude somatic Cyathostomins (CSC), and excretory-secretory Cyathostomins (ESC).

Results: The results revealed highest 437.04% and lowest 37.81% immunoglobulin G (IgG) in high and low egg shedder groups when using ESC and CSS antigens, respectively. Antibodies index for ESS and CSC were significantly higher in moderate egg shedder group while that for ESS and CSC, ESC was significantly higher in high egg shedder group. Tumor necrosis factor alpha (TNF-α)/interleukin-4 (IL-4) balance in S. vulgaris infected donkeys was approximately equal in apparently healthy, low and high egg shedder groups while TNF-α < IL-4 in moderate egg shedder. In Cyathostomins infected animals, TNF-α/IL-4 balance was approximately equal in apparently healthy group while it was low in moderate and high egg shedder groups. The diagnostic accuracy showed that the higher specificity (46.6%) and prevalence (95.40%) were recorded by CSS and ESC antigens, respectively. However, SDS-PAGE and western blotting profiling proved that the band at molecular weight 25 kDa is exhibited by CSS antigen.

Conclusion: Combination of detecting level of TNF-α/IL-4 balance, CSS antigen and IgG concentration is good tool for appropriate diagnosis of such infection. More advancement research must be done concerning Th1/Th2 balance and cross-reactivity of S. vulgaris and Cyathostomins spp. at the base of serological and molecular investigation.

Keywords: cytokines, interleukin-4, Strongylus, Th1, Th2, tumor necrosis factor alpha.

Monday, 19 June 2017

Effect of different concentrations of soybean lecithin and virgin coconut oil in Tris-based extender on the quality of chilled and frozen-thawed bull semen

Research (Published online: 20-06-2017)
17. Effect of different concentrations of soybean lecithin and virgin coconut oil in Tris-based extender on the quality of chilled and frozen-thawed bull semen
A. A. Tarig, H. Wahid, Y. Rosnina, N. Yimer, Y. M. Goh, F. H. Baiee, A. M. Khumran, H. Salman, M. A. Assi and M. Ebrahimi
Veterinary World, 10(6): 672-678


ABSTRACT

Aim: The objective of this study was to evaluate the effects of different concentrations of soybean lecithin (SL) and virgin coconut oil (VCO) in Tris-based extender on chilled and frozen-thawed bull semen quality parameters.

Materials and Methods: A total of 24 ejaculates were collected from four bulls via an electroejaculator. Semen samples were diluted with 2% VCO in Tris-based extender which consists of various concentrations of SL (1, 1.25, 1.5, and 1.75%). A 20% egg yolk in Tris used as a positive control (C+). The diluted semen samples were divided into two fractions; one for chilling which were stored at 4°C for 24, 72, and 144 h before evaluated for semen quality parameters. The second fraction used for freezing was chilled for 3 h at 4°C, packed into 0.25 mL straws and then cryopreserved in liquid nitrogen. The samples were then evaluated after 7 and 14 days. Chilled and frozen semen samples were thawed at 37°C and assessed for general motility using computer-assisted semen analysis, viability, acrosome integrity and morphology (eosin-nigrosin stain), membrane integrity, and lipid peroxidation using thiobarbituric acid reaction test.

Results: The results showed that all the quality parameters assessed were significantly (p<0.05) improved at 1.5% SL concentration in chilled semen. Treatment groups of 1, 1.25, 1.5, and 1.75% SL were higher in quality parameters than the control group (C+) in chilled semen. However, all the quality parameters in frozen-thawed semen were significantly higher in the C+ than the treated groups.

Conclusion: In conclusion, supplementation of 1.5% SL in 2% VCO Tris-based extender enhanced the chilled bull semen. However, there was no marked improvement in the frozen-thawed quality parameters after treatment.

Keywords: bull semen, cryopreservation, quality parameters, soybean lecithin, virgin coconut oil.

Sunday, 18 June 2017

Coxiellosis in domestic livestock of Puducherry and Tamil Nadu: Detection of Coxiella burnetii DNA by polymerase chain reaction in slaughtered ruminants

Research (Published online: 19-06-2017)
16. Coxiellosis in domestic livestock of Puducherry and Tamil Nadu: Detection of 
Coxiella burnetii DNA by polymerase chain reaction in slaughtered ruminants
Jothimani Pradeep, Selvaraj Stephen, Pratheesh Pooja, Anbalagan Akshayavardhini, Balakrishnan Sangeetha and Prabakar Xavier Antony
Veterinary World, 10(6): 667-671
ABSTRACT
Background and Aim: In the course of our Indian Council of Medical Research project on coxiellosis in Puducherry and Tamil Nadu, 5.64% goat, 1.85% sheep, 1.06% buffaloes, and 0.97% cattle were positive for Coxiella burnetii antibodies by enzyme linked immunosorbent assay kit (IDEXX, Liebefeld, Switzerland). In this preliminary study, we have proceeded to look for C. burnetii DNA in those antibody positive specimens employing an imported commercial C. burnetii polymerase chain reaction (PCR) kit.
Materials and Methods: Blood samples were collected during slaughtering. All 15 blood samples of antibody positive ruminants and three antibody negative samples were subjected to conventional Trans-PCR assay with a commercial PCR kit (Genekam Biotechnology AG, Duisburg, Germany). An in-house Trans-PCR was included in the study for comparison.
Results: A total of 15 antibody positive and three antibody-negative serum samples belonging to 11 goat, 4 sheep, 1 cattle, and 2 buffaloes were tested in duplicate for the presence of C. burnetii DNA by the commercial agar gel PCR kit and an in-house Trans-PCR. Only one buffalo serum sample was positive for C. burnetii with a band at 243 bp in in-house Trans-PCR.
Discussion: Seropositivity for C. burnetii need not necessarily translate into infectivity status of the animal. Conversely, seronegative ruminants can shed C. burnetii. Rapid disintegration of C. burnetii DNA during the storage period is an important impediment in QF-PCR research. This is the first time the performance of this commercial PCR kit is being validated in India.
Conclusion: Commercial PCR kit, Genekam did not identify any positive sample, probably because it targeted a larger amplicon of 687 bp.
Keywords: Coxiella burnetii DNA, coxiellosis, Trans-polymerase chain reaction.