Development of lymphocyte subpopulations in local breed chickens

Research (Published online: 19-07-2021)

18. Development of lymphocyte subpopulations in local breed chickens

Adil Sabr Al-Ogaili and Samer Sadeq Hameed

Veterinary World, 14(7): 1846-1852

ABSTRACT

Background and Aim: Local breeds of chicken are known to have relatively higher disease resistance to many endemic diseases and diseases that are highly virulent in commercial chickens. This study aimed to address the lymphocyte subpopulations in three constitutive immune system organs (thymus, bursa of Fabricius, and spleen) in 30, 8-week-old, male local breed chickens.

Materials and Methods: The T (CD3+) and B lymphocytes (Bu-1+) were identified through one-color, direct immunofluorescent staining of the thymus, bursa, and spleen lymphocytes. Likewise, two-color, direct immunofluorescent staining was performed to identify the CD4- and/or CD8-defined T lymphocytes. The proportions of T and B lymphocytes and CD4- and/or CD8 defined chicken lymphocyte subsets in lymphoid suspensions prepared from the thymus, bursa, and spleen were determined by flow cytometry.

Results: CD3+ cells, particularly those positive for CD4+CD8–, were dominant in the thymus, whereas cells expressing the Bu-1 marker were predominant in the bursa of Fabricius. The proportion of T and B cells was almost equal in the spleen, with more cells expressing the CD4–CD8+ marker in the red pulp.

Conclusion: These findings indicate that local breeds of chicken could serve as a reliable model for studying the immune system of commercial light chicken breeds, due to the similarity in the presence and the distribution of the immune cells.

Keywords: direct immunofluorescent staining, flow cytometry, local breed chickens, lymphocytes subpopulations.

Detection of African swine fever virus in pigs in Southwest Nigeria

Research (Published online: 19-07-2021)

17. Detection of African swine fever virus in pigs in Southwest Nigeria

Emmanuel Jolaoluwa Awosanya, Babasola Oluseyi Olugasa, Fufa Ido Gimba, Mohd Yusoff Sabri and Gabriel Adetunji Ogundipe

Veterinary World, 14(7): 1840-1845

ABSTRACT

Background and Aim: Nigeria experienced repeated outbreaks of African swine fever (ASF) in pig herds between 1997 and 2005 in the southwest region of the country. ASF is believed to currently be enzootic in this region. The status of enzootic transmission of ASF virus strain to pigs is; however, unknown. Twenty-three genotypes of the ASF virus based on the p72 gene are found across Africa. This study aimed to identify the current circulating field strain(s) of the ASF virus in Southwest Nigeria and characterized evolutionary trends.

Materials and Methods: DNA samples were extracted from 144 pooled blood samples obtained from 2012 to 2013 following the manufacturer's instructions. DNA was used for conventional polymerase chain reaction using primers targeting the p72 gene and amplified products sequenced with Sanger's sequencing. Sequences were analyzed for homology and phylogenetic relationships.

Results: Eleven of 144 samples (7.6%) showed bands at 950 bp. A new field strain of ASF virus of genotype I that shared ancestry with ASF virus strains or isolates from Spain and Brazil was identified among pig herds. The new strain differs phylogenetically in amino acid composition compared with previously identified ASF virus field strains.

Conclusion: The currently circulating field strain of ASF virus suggests a mutation responsible for decreased morbidity and mortality recorded in sporadic cases.

Keywords: African swine fever virus, enzootic, evolution, phylogeny, sequencing, Southwest Nigeria.

Risk factors associated with dystocia in swine

Research (Published online: 16-07-2021)

16. Risk factors associated with dystocia in swine

Nguyen Hoai Nam and Peerapol Sukon

Veterinary World, 14(7): 1835-1839

ABSTRACT

Background and Aim: Dystocia in swine can increase the stillbirth rate; however, its importance in pig-breeding systems has been underestimated. Until now, few studies have investigated dystocia and associated risk factors. Therefore, in this study, we aimed to evaluate the effects of various risk factors on dystocia in swine.

Materials and Methods: Out of 5,557 piglets, we included 4,997 piglets in risk analysis study. The dependent variable was dystocia, which was recorded when a birth interval exceeded 45 min or when obstetric assistance was applied. The independent variables were parity, gestation length, litter size, birth order, gender, presence of a dead piglet, birthweight, crown rump length, body mass index, ponderal index, and oxytocin use. We used generalized linear mixed models to examine the associations between potential risk factors and dystocia at the piglet level.

Results: A total of 6% of the piglets were born with a dystocia event, and 47.2% of the farrowing experienced at least one event. Dead piglets and piglets with a crown rump length of >31 cm were associated with an increased dystocia rate. This rate decreased from birth order 2 to 7, stabilized to 11, and then increased till the end of the fetal expulsion process.

Conclusion: Dystocia is common in swine. Therefore, this condition should be carefully addressed by veterinarians and farrowing house personnel so that its adverse effect on welfare and productivity of sows and survivability of piglets can be reduced. Further studies investigating dystocia status and risk factors in different swine farrowing systems should be undertaken to provide more knowledge about this neglected condition.

Keywords: birth order, crown rump length, dystocia, piglet, swine.

Non-infectious risk factors for intrapartum stillbirth in a swine farm in the North of Vietnam

Research (Published online: 16-07-2021)

15. Non-infectious risk factors for intrapartum stillbirth in a swine farm in the North of Vietnam

Nguyen Hoai Nam and Peerapol Sukon

Veterinary World, 14(7): 1829-1834

ABSTRACT

Background and Aim: Stillbirth causes considerable loss to the pig farming industry. Methods aimed at reducing stillbirth should base on the understanding of risk factors for intrapartum stillbirth because it accounts for 75% of all stillbirths. Unfortunately, few studies have differentiated between intrapartum and prepartum stillbirths leading to inadequate information about risk factors for sole intrapartum stillbirth. This study investigated risk factors for piglet's intrapartum stillbirth.

Materials and Methods: Data of 1527 piglets born from 103 sows in one herd were recorded. Generalized linear mixed models were used to determine the relationship between investigated risk factors and intrapartum stillbirth at the piglet level. The potential risk factors were parity, gestation length (GL), litter size (LS), birth order (BO), birth interval (BI), cumulative farrowing duration (CFD), gender, crown-rump length, birth weight (BW), body mass index, ponderal index (PI), and BW deviation.

Results: About 60% (60.2%, 62/103) litters had stillborn piglet(s), and the intrapartum stillbirth rate was 5.8% (89/1527). BW deviation (≤0.1 and >0.6 kg), LS >13, GL (<114 and >117 days), PI ≤54, and BO >10 were the most significant factors associated with increased intrapartum stillbirth. No effect of parity, sex, BI, and CFD on intrapartum stillbirth was detected.

Conclusion: These data stressed the importance of piglets' size and shape in the prediction of intrapartum stillbirth. Furthermore, large LS, high BO, short, and long GL were associated with increased intrapartum stillbirth. The results of this study suggest that procedures aimed at increasing litter homogeneity, optimizing piglets' size and shape, avoiding short and long gestation, and increasing supervision rate, especially at the second half, of the farrowing may reduce piglet's intrapartum stillbirth.

Keywords: birth weight deviation, intrapartum stillbirth, piglet, postmortem examination.

Spondias pinnata bark extract- an ameliorator of inflammatory derangement in etoposide induced mucositis: An experimental approach

Research (Published online: 15-07-2021)

14. Spondias pinnata bark extract- an ameliorator of inflammatory derangement in etoposide induced mucositis: An experimental approach

Aradhana Marathe, Gayathri M. Rao and M. Chakrapani

Veterinary World, 14(7): 1822-1828

ABSTRACT

Background and Aim: Mucositis, one of the vulnerabilities of chemotherapy, affects the physiological activities and therapeutic strategies of patients because it can affect the normal cell population. Etoposide is a commonly used chemotherapeutic agent for cancers such as oral, lung, and gastrointestinal. In addition to the abnormal metabolic processes in the body caused by tumorigenesis, new metabolic alterations can occur, such as oxidative stress, antioxidant imbalance, and inflammatory reactions, all of which can contribute to existing patient vulnerability. Therapeutic adjuvants can help overcome these toxic effects. Spondias pinnata is a tropical tree omnipresent in the coastal and Western Ghat section of India that is used for culinary purposes and as a local analgesic. Therefore, we aimed to study the anti-inflammatory effects of S. pinnata in an etoposide-induced mucositis rat model.

Materials and Methods: Small intestinal tissue homogenates from albino Wistar rats were used to estimate the levels of glutathione (GSH) and nitric oxide (NO), and activities of total antioxidant (TAO), myeloperoxidase (MPO) and Na+-K+ ATPase. The animals were grouped into: (1) normal control, (2) etoposide-induced mucositis (65 mg/kg bodyweight, single IP dose), (3) S. pinnata control group, and (4) etoposide followed by S. pinnata bark extract (200 mg/kg bodyweight, once in a day). Animals were sacrificed after 24, 48, 72, and 96 h and compared with that of the normal control group (n=6). Statistical analysis was performed using EZR software.

Results: We observed a significant decrease in the TAO and GSH levels with a marked increase in NO, MPO, and Na+-K+ ATPase activity in the mucositis group. A tendency to recover from the decreased TAO and GSH levels existed in the treated group, showing the protective effects of S. pinnata bark extract against mucositis. In addition, this extract also showed anti-inflammatory effects as reflected by the recovery in MPO levels at the end of 96 h. Maintenance of Na+-K+ ATPase activity in the treated group demonstrates the protective effects of the extract against the increased levels observed in the etoposide-induced mucositis group.

Conclusion: This study revealed the protective effects of S. pinnata bark extract against the oxidative and inflammatory changes that occurred during the development of mucositis. This would decrease the pathological burden during chemotherapy and prevent any hurdles in therapeutic modalities.

Keywords: etoposide, mucositis, oxidative and inflammatory markers.

Application of equine herpesvirus-1 vaccine inactivated by both formaldehyde and binary ethylenimine in equine

Research (Published online: 15-07-2021)

13. Application of equine herpesvirus-1 vaccine inactivated by both formaldehyde and binary ethylenimine in equine

Fatma F. Warda, Hala El Sawy Ahmed, Nermeen G. Shafik, Christine A. Mikhael, Heba M. G. Abd-ElAziz, Walaa A. Mohammed and Eman A. Shosha

Veterinary World, 14(7): 1815-1821

ABSTRACT

Background and Aim: Equine herpesvirus-1 infection in horses causes a wide range of manifestations affecting the respiratory tract. The virus can cause serious economic losses through sporadic abortion in pregnant mares, perinatal death, respiratory disease in young foals. This study was designed to prepare inactivated equine herpesvirus-1 (EHV-1) vaccine using both 0.005 M binary ethylenimine (BEI) and 0.0006% formaldehyde (FA) to decrease the use of BEI and provide a good immunological response. The efficacy, safety, and duration of immunity of the prepared inactivated EHV-1 vaccine were evaluated.

Materials and Methods: The prepared FA/BEI-inactivated EHV-1 vaccine was adjuvanted with Alhydrogel and then evaluated by inoculation into guinea pigs, followed by comparison with the commercial inactivated EHV-1 vaccine. These two vaccines were evaluated by testing the safety and immunogenicity in horses classified into two groups. Group A was vaccinated with two doses of the prepared vaccine at a 4-week interval, while Group B was vaccinated with two doses of the commercial vaccine only. Anti-EHV-1 antibodies were detected in horse serum using enzyme-linked immunosorbent assay (ELISA) and virus neutralizing test (VNT).

Results: Regarding the time required to inactivate EHV-1 vaccine, this was decreased using 0.005 M BEI and 0.0006% FA from 24 to 8 h. ELISA in Group A horses demonstrated a significant increase in EHV-1 antibody titer at 2 weeks after the booster dose compared with that for the pre-booster one, from 485 to 855 antibody titer, which then peaked at 1240 in the 3rd month post-vaccination; after that, it began to decline gradually until the 6th month. Meanwhile, in Group B, the ELISA reading increased from 420 to 790 and then peaked at 1215. The VNT mean in Group A increased from 1.1 to 2.5 within 2 weeks after administration of the booster dose, while in Group B it increased from 0.8 to 2.1. Moreover, ELISA in Group A pigs indicated mean antibody titers at the 3rd week post-inoculation of 576 for Group A and 554 for Group B.

Conclusion: The inactivated EHV-1 vaccine, with fewer chemicals, was prepared in a shorter time. It is safe and also more potent to protect horses for up to 6 months against EHV-1 infection than the commercially produced vaccine.

Keywords: binary ethylene imine, equine herpesvirus-1, formaldehyde, immunogenicity, inactivated vaccine.

Vancomycin resistant Streptococcus equi subsp. equi isolated from equines suffering from respiratory manifestation in Egypt

Research (Published online: 14-07-2021)

12. Vancomycin resistant Streptococcus equi subsp. equi isolated from equines suffering from respiratory manifestation in Egypt

Amany A. Arafa, Riham H. Hedia, Nagwa S. Ata and Eman S. Ibrahim

Veterinary World, 14(7): 1808-1814

ABSTRACT

Background and Aim: Upper respiratory tract infections are common in horses and can be caused by a variety of pathogens, mainly Streptococcus equi subsp. equi, which are a significant equine pathogen causing major health issues as well as financial losses to the equine industry. This study aimed to determine the prevalence of Streptococcal bacteria in equines in Egypt, and characterize vancomycin-resistant S. equi subsp. equi phenotypically and genotypically.

Materials and Methods: S. equi subsp. equi was isolated from internal nares of horses. All strains were confirmed by polymerase chain reaction-based detection of Streptococcus genus-specific 16S rRNA, sodA and seeI genes. Antibiotic susceptibility was determined phenotypically using the disk diffusion method. Genotypic detection of antibiotic resistance genes was performed by analyzing as β-lactamase resistance (blaZ), tetracycline resistance (tetK), vancomycin resistance (vanA), and chloramphenicol resistance (fexA).

Results: Eight streptococcal isolates were confirmed as S. equi subsp. equi. The genotypic characterization of antibiotic resistance showed resistance to vanA and tetK, with a frequency of 87.5% and 12.5%, respectively, while the frequency of sensitivity was 100% for blaz gene and fexA gene.

Conclusion: In this study, we assessed vancomycin-resistant S. equi subsp. equi from equines suffering from respiratory manifestation in Egypt.

Keywords: antibiotic resistance, equines, polymerase chain reaction, Streptococcus equi subsp. Equi, vancomycin.