Genetic variations in the Myostatin gene affecting growth traits in sheep

Research (Published online: 23-02-2021)

20. Genetic variations in the Myostatin gene affecting growth traits in sheep

Noha M. Osman, Heba I. Shafey, Mohamed A. Abdelhafez, Ahmed M. Sallam and Karima F. Mahrous

Veterinary World, 14(2): 475-482

ABSTRACT

Background and Aim: Sheep productivity in developing countries is crucial, as this animal is an essential source of meat and wool. Myostatin (MSTN) plays an important role in the regulation of muscle mass through the regulation of muscle growth, differentiation, and regeneration. The present study sought to investigate genetic variation in the first intron of the MSTN gene and the association of variants with growth traits in major sheep breeds in Egypt (Barki, Ossimi, and Rahmani) and Saudi Arabia (Najdi) using polymerase chain reaction (PCR) and sequencing.

Materials and Methods: Blood samples were collected, and DNA was extracted from 75 animals. A 386 bp fragment in the first intron of the MSTN gene was amplified using PCR. Polymorphic sites were detected using direct sequencing and then correlated with growth traits using a general linear model.

Results: Sequence analysis of the first intron of MSTN gene identified six single-nucleotide polymorphisms (SNPs) in the studied breeds. Four mutual SNPs were determined: c.18 G>T, c.241 T>C, c.243 G>A, and c.259 G>T. In addition, two SNPs c.159 A>T and c.173 T>G were monomorphic (AA and TT, respectively) in the Ossimi, Rahmani, and Najdi breeds and polymorphic in the Barki breed. The association analysis revealed that the c.18 G>T and c.241 C>T significantly associated (p<0.05) with birth weight and average daily weight gain, respectively.

Conclusion: Our results strongly support MSTN as a candidate gene for marker-assisted selection in sheep breeding programs. Furthermore, the identified variants may be considered as putative markers to improve growth traits in sheep.

Keywords: growth traits, Myostatin gene, polymorphism, sheep.

Investigation of Sarcocystis spp. in slaughtered cattle and sheep by peptic digestion and histological examination in Sulaimani Province, Iraq

Research (Published online: 22-02-2021)

19. Investigation of Sarcocystis spp. in slaughtered cattle and sheep by peptic digestion and histological examination in Sulaimani Province, Iraq

Shadan Hassan Abdullah

Veterinary World, 14(2): 468-474

ABSTRACT

Background and Aim: Sarcocystosis is a zoonotic infection caused by various species of Sarcocystis organisms with a worldwide geographic distribution. This study investigated the presence of Sarcocystis organisms in cattle and sheep slaughtered at an abattoir in Sulaimani Province in North Iraq.

Materials and Methods: A total of 130 muscle samples were collected during May, June, and July of 2020, including 80 samples from sheep and 50 samples from cattle. Samples were examined visually for macrosarcocysts. The peptic digestion method was used to analyze fresh muscle tissue samples for detecting microsarcocysts followed by microscopic examination. Furthermore, muscle samples were fixed and stained with hematoxylin and eosin for histopathological examination.

Results: In the gross examination, macroscopic cysts were not detected in both cattle and sheep; hence, all the prevalence data were obtained through microscopic observation of muscle samples. The peptic digestion method revealed the presence of banana-shaped bradyzoites in 90% and 92.5% of slaughtered cattle and sheep muscle samples, respectively. Organ-wise prevalence revealed that 95% and 92% of esophageal samples of sheep and cattle contained Sarcocystis spp., respectively. Moreover, 90% and 88% of sheep and cattle diaphragms were respectively infected. Histopathological examination of tissue sections revealed two morphologically distinct types of microsarcocysts, including thin-walled and thick-walled, in both sheep and cattle.

Conclusion: The suspected Sarcocystis spp. were Sarcocystis tenella and Sarcocystis arieticanis in sheep and Sarcocystis cruzi and Sarcocystis bovifelis or Sarcocystis hominis in cattle. Infective stages of different Sarcocystis spp. are widespread in the study area environment.

Keywords: cattle, muscle samples, prevalence rate, Sarcocystis, sheep.

Evaluation of the acute toxicity of the extracts of Anacyclus pyrethrum var. pyrethrum (L.) and Anacyclus pyrethrum var. depressus Maire in Swiss mice

Research (Published online: 22-02-2021)

18. Evaluation of the acute toxicity of the extracts of Anacyclus pyrethrum var. pyrethrum (L.) and Anacyclus pyrethrum var. depressus Maire in Swiss mice

Fatima Zahra Jawhari, Abdelfattah El Moussaoui, Hamada Imtara, Hamza Mechchate, Imane Es-Safi, Mohamed Bouhrim, Loubna Kharchoufa, Achraf Miry, Dalila Bousta and Amina Bari

Veterinary World, 14(2): 457-467

ABSTRACT

Background and Aim: Anacyclus pyrethrum (L.) has been used in traditional North African and Indian medicine for the treatment of several diseases such as cancer, rheumatism, epilepsy, diabetes, and Alzheimer's disease. Despite its medical benefits, few studies have examined its toxicity. The present study evaluated the acute toxicity of hydroethanolic extracts of different parts (roots, seeds, leaves, and capitula) of two varieties of A. pyrethrum (L.), namely, A. pyrethrum var. pyrethrum (L) and A. pyrethrum var. depressus (Ball) Maire, in mice.

Materials and Methods: Acute toxicity was evaluated after the oral administration of different extracts at doses of 300, 500, and 2000 mg/kg. Mortality, body weight, general behavior, and adverse effects were observed daily for 14 days. At the end of the experiment, mice were sacrificed, and biochemical parameters and histopathology of the liver, kidneys, and spleen were analyzed.

Results: The extracts of different parts of both plants induced no signs of toxicity or mortality during the observation period, excluding capitulum and seed extracts, which induced slight sedation at a dose of 2000 mg/kg. The LD50 of the extracts was estimated to exceed 2000 mg/kg. The administration of A. pyrethrum var. pyrethrum roots at a dose of 300 mg/kg resulted in significantly increased AST levels. However, the A. pyrethrum var. depressus root extract induced significant increases in the levels of both transaminases (alanine aminotransferase [ALT] and aspartate aminotransferase [AST]). The remaining extracts of both plants at a dose of 500 mg/kg significantly increased AST levels. Moreover, all plant extracts excluding the A. pyrethrum var. pyrethrum capitulum extract at 2000 mg/kg provoked significant increases in AST levels, and A. pyrethrum var. depressus roots provoked a significant increase of ALT levels. Meanwhile, mice treated with high doses of extracts (2000 mg/kg) displayed histopathological changes in the liver, kidneys, and spleen characterized by hepatic distress, inflammatory infiltration, focal tubular necrosis, vascular congestion, and lymphoid hyperplasia.

Conclusion: The results of the present study indicate that the hydroethanolic extracts of different parts of two varieties of A. pyrethrum (L.) were not toxic in mice at low concentrations, whereas some toxic effects were detected in mice treated at 2000 mg/kg.

Keywords: acute oral toxicity, Anacyclus pyrethrum var. depressus (Ball) Maire, Anacyclus pyrethrum var. pyrethrum (L), histopathology, serum biochemistry analysis.

Effect of adding growth factors during in vitro maturation on the developmental potentials of ewe oocytes selected by brilliant cresyl blue staining

Research (Published online: 22-02-2021)

17. Effect of adding growth factors during in vitro maturation on the developmental potentials of ewe oocytes selected by brilliant cresyl blue staining

Mohamed Fathi and Amr F. Elkarmoty

Veterinary World, 14(2): 452-456

ABSTRACT

Aim: Several factors had been concerned with the developmental competence of the sheep oocyte. This study aims to investigate the effect of adding growth factors (insulin-like growth factor 1 [IGF-1] and epidermal growth factor [EGF]) in the maturation medium of ewe oocytes selected based on brilliant cresyl blue (BCB) screening on in vitro maturation (IVM), fertilization, and pre-implantation embryo development.

Materials and Methods: Cumulus-oocyte complexes (COCs) were obtained from the ovaries of slaughtered ewes by either aspiration or slicing techniques. COCs were in vitro matured in a medium containing IGF-1 and EGF (control group). For BCB screening, oocytes were stained and divided into BCB+ oocytes that matured in the same maturation conditions without adding growth factors (Group 2) or in the presence of growth factors (Group 3), and BCB– oocytes that matured in medium without growth factors (Group 4) or with growth factors (Group 5).

Results: The supplementation of the maturation medium with growth factors during IVM of (BCB+) oocytes resulted in a significant increase in nuclear maturation rate (90.9%), fertilization rate (75.6%), and embryo developmental rates (60.0%, 46.7%, and 33.3% for cleavage, morula, and blastocyst, respectively).

Conclusion: Culturing BCB+ oocytes in a maturation medium containing both EGF and IGF-1 showed a significant improvement in nuclear maturation, fertilization, and pre-implantation embryo development in vitro.

Keywords: brilliant cresyl blue, embryo development, growth factors, In vitro fertilization, sheep.

Prevalence and distribution of soil-transmitted helminth infection in free-roaming dogs in Bali Province, Indonesia

Research (Published online: 22-02-2021)

16. Prevalence and distribution of soil-transmitted helminth infection in free-roaming dogs in Bali Province, Indonesia

Kadek Karang Agustina, Made Suma Anthara, Nengah Anom Adi Nugraha Sibang, Wayan Adi Rinta Wiguna, Jendra Krisna Apramada, Wayan Nico Fajar Gunawan, Ida Bagus Made Oka, Made Subrata and Nengah Kerta Besung

Veterinary World, 14(2): 446-451

ABSTRACT

Background and Aim: Several free-roaming dogs can be easily found in the public areas of Bali. They go out in search of foods and friends and defecate everywhere. In general, these groups of dogs do not receive good healthcare from their owners and are generally threatened by some disease-causing organisms, especially helminths. This study was conducted to identify and measure the prevalence of soil-transmitted helminths (STHs) that cause infection in free-roaming dogs in Bali Province, Indonesia.

Materials and Methods: A total of 1611 fresh dog fecal samples were collected from all areas of Bali Province and subjected to qualitative fecal examination using flotation techniques to obtain STH eggs.

Results: The incidence of STHs in free-roaming dogs was 38.36%. However, three types of STHs were identified, including Ancylostoma spp., Ascaris spp., and Trichuris spp. Ancylostoma spp. had the highest prevalence of 37.8%, followed by Ascaris spp. and Trichuris spp. at 6.02% and 0.87%, respectively. Multiple infections of these worms were also recorded. The polyparasitism prevalence of Ancylostoma spp. and Ascaris spp. was 3.85%, followed by that of Ancylostoma spp. and Trichuris spp. at 0.5% and that of Ascaris spp. and Trichuris spp. at 0.06%. There were no altitude-wise differences in the prevalence of STH infection.

Conclusion: The prevalence of STHs was high in free-roaming dogs. This finding necessitates more serious attention as it affects both animal and public health.

Keywords: Ancylostoma spp., Ascaris spp., Bali, distribution, free-roam dogs, prevalence, soil-transmitted helminth, Trichuris spp.

Antimicrobial-resistant non-typhoidal Salmonella enterica prevalence among poultry farms and slaughterhouses in Chitwan, Nepal

Research (Published online: 20-02-2021)

15. Antimicrobial-resistant non-typhoidal Salmonella enterica prevalence among poultry farms and slaughterhouses in Chitwan, Nepal

Peter D. Fowler, Sumit Sharma, Dhan Kumar Pant, Subir Singh and Melinda J. Wilkins

Veterinary World, 14(2): 437-445

ABSTRACT

Background and Aim: Antibiotic-resistant infections are one of the leading threats to public health globally. Indiscriminate use of antibiotics in food animal production is an important driver of resistance, particularly among foodborne pathogens such as non-typhoidal Salmonella enterica (NTS). While there has been extensive research on antimicrobial-resistant (AMR) S. enterica in India and China, there have been few studies in countries in South Asia, including Nepal. This is particularly important with the rise of commercial poultry farming in Nepal as a means of economic development and nutritional subsistence. This descriptive study seeks to identify the prevalence and resistance patterns of NTS serotypes focusing on Chitwan, Nepal's leading poultry producing district.

Materials and Methods: A mixture of purposive and judgment sampling of 18 poultry farms and 20 slaughterhouses representing a broad geographic distribution across multiple municipalities in Chitwan was conducted in May 2019. Environmental samples taken from poultry farms included: Water, litter, feces, feed, farm swabs, and eggshell swabs. Biological samples taken from nearby slaughterhouses included: Muscle, heart, liver, skin, cecum, crop, and spleen. Samples were cultured and tested for the presence of NTS. Positive isolates were serotyped and tested for antimicrobial susceptibility to seven antibiotics known to be important to both human and animal health regionally. Farm practices were also characterized through a survey, the results of which are detailed in the accompanying paper.

Results: Out of 708 samples (288 environmental and 420 biological), 103 (15%) tested positive for NTS (9% of environmental; n=26, 18% of biological; n=77). The percentage of positive environmental and biological samples varied by source. Environmental sample positive rates were water (27.5%), feces (10.6%), litter (8.6%), farm swabs (5%), feed (1.8%), and eggshells (0%). Biological sample positive rates were skin (28%), heart (23%), crop (20%), muscle (15%), liver (15%), spleen (15%), and cecum (12%). Out of 103 positive S. enterica isolates, 48.5% were identified as Salmonella Typhimurium, 35% Salmonella Enteritidis, 7.8% Salmonella Gallinarum, 4.9% Salmonella Virchow, and 3.9% were Salmonella Agona. Of the 103 positive isolates, 80 (78%) were resistant to at least one antibiotic, and 21 (20%) were multidrug-resistant (MDR).

Conclusion: NTS is highly prevalent among Chitwan's growing poultry industry with higher rates of positivity found in slaughterhouse samples compared with environmental samples from farms. In addition, a high rate of AMR (78%) was revealed, and an extremely concerning number of those were shown to be MDR (20%). This baseline data has important implications for poultry production and consumption in the region. Further research will elucidate the extent to which this contamination and drug resistance is impacting the health of the local population and help inform treatment and management strategies.

Note: The characterization of the poultry industry and practices that might be linked to NTS contamination in the Chitwan district are detailed in the previous paper in this series (www.veterinaryworld.org/Vol.14/February-2021/14.pdf).

Keywords: antibiotic resistance, Nepal, non-typhoidal Salmonella, poultry, serotype.

Prevalence of non-typhoidal Salmonella and risk factors on poultry farms in Chitwan, Nepal

Research (Published online: 20-02-2021)

14. Prevalence of non-typhoidal Salmonella and risk factors on poultry farms in Chitwan, Nepal

Sumit Sharma, Peter D. Fowler, Dhan Kumar Pant, Subir Singh and Melinda J. Wilkins

Veterinary World, 14(2): 426-436

ABSTRACT

Background and Aim: Poultry is becoming an increasingly important source of protein in the Nepalese diet. The Chitwan region of Nepal is the hub of the emerging poultry industry. Little is known about the prevalence of non-typhoidal Salmonella (NTS) on poultry farms or the role of farm management practices that may contribute to the presence of NTS on farms. The role of poultry in the transmission of Salmonella enterica to humans is also poorly defined. This descriptive study seeks establish baseline data through estimation of the prevalence of NTS on broiler and layer operations in various farms of the Chitwan district of Nepal.

Materials and Methods: Based on district documents on poultry production and meat marketing, a purposive sampling of 18 commercial poultry farms comprising ten broilers farms and eight layers farms was conducted. Environmental samples including water, litter, feces, feed, farm, and eggshell swabs were randomly collected from each farm. Samples were cultured and tested for the presence of NTS; positives were serotyped, and antimicrobial susceptibility determined. A comprehensive farm and practice questionnaire was administered to each farm manager.

Results: The farm level point prevalence rate was 55% (10 of 18 farms) for S. enterica. Of the total 288 farm environmental samples collected, 26 samples (9%) were positive. The rate of isolation varied according to the origin of samples: Water (27.5%), feces (10.6%), litter (8.6%), farm swabs (5%), feed (1.8%), and eggshells (0%). Farm management variables/risk factors are summarized and categorized as non-modifiable and modifiable for analysis. Broiler operations were more likely to be positive than layer operations as were poultry houses with two or less open sides. All-in/all-out management style was found to be protective. Due to the small sample size (18 farms), no associations reached statistical significance.

Conclusion: Based on environmental sampling results, NTS is highly prevalent on the poultry farms in the Chitwan district of Nepal. Certain risk factors are associated with finding NTS on farms. Our findings are generally in agreement with other studies in similar countries with rapidly emerging poultry industries. The identification of risk factors provides owners, technicians, and veterinarians with some guidance to help reduce the prevalence of NTS on farms. This baseline data are critical to understanding the epidemiology of zoonotic strain of NTS in the region and are necessary for the design of future studies and mitigation plans and underlines the need for a one-health approach to protect public health-related to Salmonella spp. from poultry farms.

Keywords: farm risk factors, Nepal, non-typhoidal Salmonella, poultry, Salmonella enterica.