<div>Background: Rice is the most important human food crop in the world and its production is affected by various biotic and abiotic stress including low soil fertility. Zinc deficiency is one of the most important micronutrient deficiencies limiting rice yield. The vast reserve of germplasm of rice grown in different eco systems could be screened to exploit the genotypic differences bfor zinc deficiency tolerance. With the advent of molecular markers, association mapping strategy based on non-random associations between causative loci and phenotype could be employed to resolve the complex traits like zinc deficiency tolerance. With this background, the current study is focused to explore the extent of variability for zinc deficiency tolerance using zinc deficiency score and quantitative traits among 44 germplasm accessions and to identify quantitative trait loci associated with zinc deficiency tolerance using Simple Sequence Repeat (SSR) marker-based association mapping. 
 
Methods: A set of 44 accessions consisting of landraces and improved varieties were selected based on their zinc deficiency score in field (Zn=0.64 ppm) screening experiment conducted in Regional Research Station, Paiyur, Tamil Nadu. Eight accessions from each Zn Def score group along with four other genotypes namely Savulu Samba, Kotta Nel, Paiyur 1 and ADT 39 were chosen for the study. Molecular analysis was carried out among the selected accessions using a total of 40 random Simple Sequence Repeat (SSR) primers. 
 
Result: Our study revealed the existence of diversity at molecular level among the selected accessions. Clustering analysis separated the accessions in two major clusters which were in accordance with the population structure analysis which resulted with two sub-populations. Through our study we identified certain accessions namely, Karuppu Nel, Manipur Local and BAM 440 which recorded high yields along with least zinc deficiency scores implying their ability to act as donors for zinc deficiency tolerance under submerged condition. Subsequent association analysis which resulted in putative association of zinc deficiency score with critical plant traits such as plant height and number of productive tillers, revealed that association mapping could be a viable strategy for understanding genetic mechanism of zinc deficiency tolerance in rice.</div>

<div>Study on Analysis of Molecular Diversity and Trait Association for Zinc Deficiency Tolerance in Rice under Submerged Conditions</div>

<div>Background: Given that Mycoplasma synoviae (MS) has the potential to cause serious respiratory illness in chicken and cause significant financial loss to farmers, the present work was designed to investigate the MS-derived pathology along with detailed molecular study of the MS organism, isolated from natural cases of MS infection. 
 
Methods: The work was carried out in the Department of Veterinary Pathology, College of Veterinary Sciences and Animal Husbandry, Durg, Chhattisgarh, for the period of two years which was ended on October 2021. Total 428 birds were included in this study. Tissue samples from the suspected cases of MS infection were collected and stored at -20&deg;C and 10% formalin for molecular analysis and histopathological study respectively. Tissues were collected from respiratory organs along with liver, kidney and spleen.&nbsp; 
 
Result: Overall prevalence of MS in the Chhattisgarh state was recorded as 6.30% under present investigation. Genome sequence of the PCR positive amplicon from MS confirmed case isolated from Chhattisgarh showed 99% homology with the other genome sequences available in NCBI website. Phylogenic analysis revealed highest similarities of Chhattisgarh isolate with the isolates of China and Iran that were imported from the GenBank. There were various degenerative, inflammatory and necrotic lesions was found in the respiratory system along with liver, kidney and spleen of MS positive birds.</div>

Mycoplasma synoviae Based Molecular, Phylogenic and Pathological Studies in Chickens

<div style="text-align: justify;">The study was undertaken to understand the genetic architecture of Deccani and Nellore sheep breeds and to assess the genetic distance between the breeds. Allele diversity, genetic variability and population structure in the two breeds were estimated using 30 microsatellite markers. A total of 100 sheep, 50 each from Deccani and Nellore breeds were genotyped. The total number of alleles observed was 254 and 260 in Deccani and Nellore, respectively. The mean expected heterozygosity among the breeds ranged from 0.79 (Deccani) to 0.80 (Nellore) whereas the mean observed heterozygosity levels ranged from 0.77 in Deccani to 0.78 in Nellore sheep. The overall mean inbreeding coefficient was 0.029 in Deccani and 0.031 in Nellore sheep and of the 30 loci studied, 14 loci in Deccani and 16 loci in Nellore sheep showed negative inbreeding coefficient indicating the presence of outbreeding. However, eight loci (BM1314, BM6506, BM8125, ILSTS28, MAF70, MCM140, OarCB226 and OarFCB128) showed positive, mild to moderate inbreeding ranging from 0.007 to 0.25 in Deccani and 0.066 to 0.37 in Nellore sheep studied. &nbsp;The FIS values ranged from -0.372 to 0.74, FST values ranged from 0.001 to 0.172 and FIT values ranged from -0.370 to 0.728 between the Deccani and Nellore sheep breeds studied. The PIC values ranged from 0.498 to 0.886 with a mean of 0.773 in Deccani and from 0.574 to 0.894 with a mean of 0.777 in Nellore breed. The information generated from the present study will be valuable for setting conservation priority of these two breeds.</div>

Molecular genetic studies on Nellore and Deccani sheep using microsatellite markers

<div>Background: Severe Combined Immuno Deficiency (SCID) is a heritable deficiency transmitted through autosomal recessive gene, carried on by purebred Arabian and crossbred horses. A deletion of five base pairs at the gene encoding the catalytic subunit of the Protein Kinase DNA-dependent (DNA-PKcs) is responsible for this disease and SCID-affected animals always die in the first six months of life. Considering this problem, it is important to perform a molecular epidemiological study to estimate the frequency of the SCID allele in Arabian purebred horses in Tunisia. 
 
Methods: The DNA of the peripheral blood lymphocytes of 164 purebred Arabian horses belonging to the Sidi Thabet stud was extracted by the spin-column method, in order to verify the quality of the DNAs used, the samples were dosed by a spectrophotometer. The amplification of the DNA was carried out by two specific primers in a Polymerase Chain Reaction (PCR) to flank the deletion zone of the DNA sample by adding to each PCR sample a marker or a standard of size knowing that the fragment we wanted to amplify is composed of 163 base pairs. Then, the PCR products were sequenced using an automatic sequencer.&nbsp; 
 
Result: By analyzing the electropherograms results, we noted the absence of the SCID deletion in the studied group of Arab purebreds. Hence, it is essential to carry out molecular screening of the SCID deletion in other sites in order to determine its prevalence in the country&rsquo;s purebred Arabian horse population.</div>

<div>Epidemiological Molecular Study of Combined Severe Immune Deficiency in Arabian Horses in Tunisia</div>

A study was carried out using twenty diverse speciality corn genotypes of QPM, sweet corn, pop corn and baby corn to investigate morphological and molecular diversity in speciality corn during kharif, 2015, at Instructional Farm of Rajasthan College of Agriculture, Udaipur. Morphological observations recorded, variability parameters and correlation coefficient were computed and DNA analysis was also used. The investigations revealed that sufficient variability existed in the material as characters like grain yield, stover yield, biological yield, TSS, test weight and cob height exhibited high estimates of GCV, PCV and heritability. Further some characters showed significant positive genotypic and phenotypic correlation with grain yield. Baby corn genotype HM-4 exhibited the highest performance for grain yield followed by QPM genotypes, HQPM-1, sweet corn, Madhuri and pop corn Amber pop corn identified as the best performers for grain yield/plant and most of the contributing characters. Molecular characterization through RAPD analysis also revealed high polymorphism and marked genetic diversity among the speciality corn genotypes as also reflected by their morphological differences.&nbsp;

Studies on morphological and molecular diversity in speciality corn ( Zea mays L.)

<div style="text-align: justify;">The present study was intended to investigate the sensitivity of different tissues of tumorous and non-tumorous birds to the polymerize chain reaction-baseddiagnosis of Marek&rsquo;s disease. Tissue samples were collected from spleen, sciatic nerve, feather follicles and tumour parts (if any)of chickens during the routine necropsy examination. The presence of Marek&rsquo;s disease virus was examined using primers for 132 bp repeats of BamHI-H regionand positive samples were sequenced for 132 bp repeats and Meq gene. In the birds showing tumours, various samples such as the spleen, feather pulp, sciatic nerve and tumour tissue yielded positive results in &nbsp;92.31%, 88.46%, 100% and 100% cases respectively. Amongst non-tumorous birds, 11.53% spleen, 23.07% feather pulp and 11.53% sciatic nerve were found positive. This is the first comparative study between nerve and other organs samples for molecular diagnosis of Marek&rsquo;s disease. Data generated shows that the probability of false negative in tumorous birds and false positive in non-tumorous birds was comparatively low while employing nerve tissue than spleen and feather follicles. Thus, it may be concluded from our study that nerves are a more reliable and robust diagnostic organ in comparison to the other organs used for conventional diagnosis.</div>

Comparative study on biological material for molecular diagnosis of Gallid herpesvirus 2

Background: Classical swine fever (CSF) continues to be a persistent threat to pig production in North-Eastern states of India, including Assam. This study aimed to investigate the molecular epidemiology of &ldquo;Classical swine fever virus (CSFV)&rdquo; by analysing the NS5B gene from field samples collected between 2021 and 2023. 
&nbsp; 
Methods: Tissue specimens from CSF-suspected pigs from various districts of Assam were examined for pathological lesions. Molecular diagnosis was performed using reverse transcription-PCR (RT-PCR) targeting the NS5B gene, followed by sequencing and phylogenetic analysis. 
&nbsp; 
Result: Pathological findings revealed typical CSF-associated lesions, including necrotizing tonsillitis, haemorrhagic pneumonia, renal cortical haemorrhages, lymphoid depletion and splenitis with infarction at the edges. Reverse transcription &ndash; PCR assay on tissue samples confirmed the presence of CSFV. Nucleotide sequences and phylogenetic analysis based on the 449 bp fragment of NS5B gene revealed that the circulating CSFV belonged to the genotype 2 and subgroup 2.2. The field isolates shared high nucleotide identity (92.63 to 99.57%) among themselves and clustered closely with known subgroup 2.2 reference strain from India with 94.36% to 95.30% nucleotide homology. This study provides evidence of increasing co-circulation of subgroup 2.2 CSFV strains in Assam and highlights the utility of NS5B-based phylogeny for understanding CSFV evolution and informing control strategies. 
&nbsp;

Molecular Epidemiological Studies on Classical Swine Fever Virus in Pig Population of Assam, India

<div>Sclerotium rolfsii is a soil borne fast spreading fungal pathogen that causes collar rot in chickpea. The variability among the pathogen isolates have made difficult to design efficient management practices and necessitates for a comprehensive study to know its diversity. The present study was planned to study the genetic diversity among the isolates of S. rolfsii collected from chickpea growing regions of Kurnool and Ananthapur districts of Andhra Pradesh at morphological and molecular level. The morphological characterization of isolates on PDA indicated that the isolates, CSR 14, CSR 18 and CSR 20, were fast growing and the overall growth i.e., sclerotia formation in terms of number, size and days to formation, was also faster. These isolates took only 4 days for production of sclerotial bodies. A total of 254 reproducible and scorable polymorphic bands ranging from 200 to 2000 bp were observed with twenty nine RAPD primers. The RAPD banding pattern reflected the presence of greater variability among the isolates and grouped the isolates into two clusters. The isolates, CSR 18 and 20, formed the cluster II revealing their distantness from other isolates at molecular level. The isolate, CSR 14, formed a separate sub cluster in the cluster I indicating its distant association with other isolates of this cluster.</div>

<div>Studies on Diversity of Sclerotium rolfsii Causing Collar Rot in Chickpea using Morphological and Molecular Markers</div>

Background: The Karacadağ Mountains are of extinct volcanic origin and cover a large area in the triangle between Diyarbakır (Center, Nar and Ergani districts), Şanlılurfa (Siverek and Viranşehir districts) and Mardin (Derik district). Agricultural activities are limited due to the stony structure of the region; therefore, small animal husbandry is intensively practiced in the villages of the region. Mahalli goats, which are morphologically new domestic goats, are distinguished from other domestic goats by their spiral horn structure. They are not only resistant to cold weather conditions, but also resistant to diseases. Therefore, present study aimed to determine the genetic diversity and phylogenetic relationships of Mahalli goats in Diyarbakır region. 
 
Methods: The study was carried out at Şanlıurfa, Harran University of Agricultural Faculty, Laboratory of Animal Biotechnology and Molecular Genetics, in 2019-2020. Out of 24 Mahalli goats, forward and reverse primers were used to amplify the 598 bp region over the mtDNA D-loop region encompassing the 481 bp most variable region (HVR1). Analysis of goat D-loop sequences revealed 481 regions of 0.378 G+C, 97 polymorphic regions and 19 haplotypes. The phylogenetic analysis of Mahalli goats was carried out using molecular genetic techniques. 
 
Result: As a result of data analysis, both haplotype diversity (HD) and nucleotide diversity (ND) were calculated to be 1.000&plusmn;0.0039 and 0.0375&plusmn;0.00209, respectively. The genetic distance between the haplotypes of Mahalli goat ranged from 0.003 to 0.087 and the genetic distance between the haplotypes of Mahalli goat and other domestic goat breeds in Turkey ranged from 0.016 to 0.027. All 19 haplotypes used in this study were represented in the lineage A phylogenetic tree.

A Mitochondrial DNA-based Molecular Phylogenetics Study of the Mahalli Goat as a New Animal Genetic Resource in Southern Anatolia in Turkey

Background:&nbsp;Mannheimia is a Gram-negative, facultative anaerobe, non-spore forming and non-motile bacteria belongs to the family Pasteurellaceae. Caprine bacterial pneumonia is most often caused by Mannheimia haemolytica (previously known as Pasteurella haemolytica) and Pasteurella multocida which are more frequently associated with the outbreak of acute pneumonia and death of goats, particularly young once. Mannhemia is an opportunistic pathogen that particularly inhabits the nasopharynx and tonsils of goat and sheep. The present study was aimed to study Mannheimiosis in Guwahati, Assam in order to diagnose and control the disease among goats. 
 
Methods: The present investigation was conducted during the year 2021-2022 in Guwahati, Assam. A total of 51 pneumonic lung samples were collected from nearby slaughter houses and during necropsy at Department of Pathology, C.V.Sc., A.A.U., Khanapara, Guwahati-22. All the samples were subjected to primary isolation in blood agar and MacConkey&#39;s agar and further confirmation was made using PCR. 
 
Result: Out of total 51 pneumonic lung samples examined seven (13.72%) cases were found positive for Mannheimia haemolytica infection where 5 cases were found to be associated with other respiratory pathogens.&nbsp;Visible gross lesions observed during necropsy were broncho-interstitial pneumonia, suppurative pneumonia and fibrinous pneumonia with hemorrhagic tracheitis. Histopathological examination revealed presence of characteristic oat cells, intravascular thrombosis, fibrin balls, oedema, necrosis and polymorphonuclear cell infiltration in the lungs. Bacteriological culture for isolation and identification of Mannheimia haemolytica showed &beta; haemolytic zone on MLA plates. Confirmatory diagnosis was made using PCR targeting 16s rRNA gene with amplicon size 1500 bp and Lkt gene with amplicon size 206 bp. The phylogenetic analysis of 16s rRNA gene from positive sample showed percent identity of above 97% with other strains of Mannheimia haemolytica present in NCBI website. The variability in the lesions observed in the present study it can be concluded that a mixed infection with reduced resistance of the animals contributed to the development of pneumonia rather than Mannheimia haemolytica alone and PCR can be used as reliable technique for confirmatory diagnosis of respiratory mannheimiosis.