Selection Programs Research Articles

Genomic prediction model optimization for growth traits of olive flounder (Paralichthys olivaceus)

Genomic prediction (GP) has emerged an effective tool for addressing the many shortcomings of traditional selective breeding, thereby enhancing the selection process. In this study, we optimized GP methods using 5-fold cross-validation to estimate genome-estimated breeding values for the weight traits of olive flounder (Paralichthys olivaceus). To accomplish our goal, we determined the parentage of the target broodstock and the ability of 11 prediction models to predict the weight traits of 1.8-year-old olive flounders, which were genotyped using a 70 K single nucleotide polymorphism (SNP) array. Moreover, our optimization efforts toward the predictive ability of genomic best linear unbiased prediction (GBLUP), Bayesian B (BB), and random forest (RF) methods encompassed changes in various aspects such as fixed effects, SNP quantity, population size, and phenotypic data collected at different fish ages. Additionally, we assessed the predictive ability for the total length and body depth of fish using GBLUP, BB, and RF. Among the 11 prediction methods used in this study, the BB (0.675), Elastic Net (0.679), and RF (0.698) methods exhibited the highest predictive abilities, whereas the GBLUP (0.637) method demonstrated the lowest. Incorporating information regarding fish sex as a fixed effect substantially improved the predictive ability of GBLUP and BB. For mean models, utilizing 3000–5000 random SNP markers resulted in a higher predictive ability, similar to that obtained using 50,000 SNPs. Increasing the population size reduced the standard deviation of the predictive ability. Notably, phenotypic records from 1.8-year-old fish exhibited a significantly higher predictive ability than those from the other age groups. Furthermore, GBLUP, BB, and RF provided higher predictive abilities for length (0.655–0.852) and body depth (0.665–0.861). These findings may significantly shape future olive flounder genomic selection programs and offer valuable insights into GP in aquaculture.

MEF2D Functions as a Tumor Suppressor in Breast Cancer.

The myocyte enhancer factor 2 (MEF2) gene family play fundamental roles in the genetic programs that control cell differentiation, morphogenesis, proliferation, and survival in a wide range of cell types. More recently, these genes have also been implicated as drivers of carcinogenesis, by acting as oncogenes or tumor suppressors depending on the biological context. Nonetheless, the molecular programs they regulate and their roles in tumor development and progression remain incompletely understood. The present study evaluated whether the MEF2D transcription factor functions as a tumor suppressor in breast cancer. The knockout of the MEF2D gene in mouse mammary epithelial cells resulted in phenotypic changes characteristic of neoplastic transformation. These changes included enhanced cell proliferation, a loss of contact inhibition, and anchorage-independent growth in soft agar, as well as the capacity for tumor development in mice. Mechanistically, the knockout of MEF2D induced the epithelial-to-mesenchymal transition (EMT) and activated several oncogenic signaling pathways, including AKT, ERK, and Hippo-YAP. Correspondingly, a reduced expression of MEF2D was observed in human triple-negative breast cancer cell lines, and a low MEF2D expression in tissue samples was found to be correlated with a worse overall survival and relapse-free survival in breast cancer patients. MEF2D may, thus, be a putative tumor suppressor, acting through selective gene regulatory programs that have clinical and therapeutic significance.

Geographic mobility of college students and the gender gap in academic aspirations

We study the decision to pursue an advanced degree from an internationally renowned academic institution, which greatly facilitates access to top jobs. Relying on unique data on applications to a highly selective program that provides graduate fellowships to Spanish students, we show that women in non-STEM fields apply to the fellowships at lower rates than males with the same GPA and in the same field of study. On the contrary, our estimates imply that females in STEM apply at equal, or higher, rates than comparable males in the same fields. We also find that female students are relatively less interested in doctoral programs and less willing to study abroad than males. To shed light on the mechanisms, we surveyed college students about their post-graduation plans. The lower geographic mobility of female students (in non-STEM fields) appears linked to females’ lower earnings expectations and a gender-asymmetric detrimental effect of involvement in romantic relationships.

Estimation of genetic parameters for reproductive traits evaluated by ultrasonography in Senepol heifers

Studies on reproductive tract score (RTS) and antral follicle count (AFC) in Senepol cattle are limited. These traits are essential as they are linked to the reproductive ability and reproductive performance of animals. Understanding the heritability and genetic correlation of these traits is crucial for guiding selection programs and selecting animals with greater reproductive efficiency and higher production potential. Therefore, this study aimed to estimate the genetic parameters of weight, RTS, and AFC in Senepol cattle using transrectal ultrasonography. Reproductive data were collected from 850 female Senepol cattle aged 10-16 months. At the time of evaluation, the following were measured: RTS traits (scores from 1 to 5), AFC (0 to 100), and female weight (kg). Variance and covariance components, genetic heritability, and correlations were estimated by univariate and bivariate analyses using the bull model. Heritability estimates were moderate for AFC (0.52) and weight (0.46), and low for RTS (0.12). The genetic correlation between RTS and AFC was almost zero (-0.05). The estimated genetic correlation between weight and AFC was -0.41, while the correlation between weight and RTS was 0.48. Selective breeding of AFC and RTS can enhance the reproductive efficiency of the herd and result in animals with earlier pubertal age and increased fertility.

Fiber characteristics of the dromedary camel in the Arabian Peninsula

Dromedary camel fibers have long been utilized to make clothes, tents, ropes, mats, and carpets, however, only a minority of these fibers are currently used to produce textiles. Dromedary fiber classification based on quality traits is essential to investigate its textile potential. Therefore, the objectives of this study were to (1) develop a classification protocol for dromedary camel fibers based on crimp (i.e., shape), (2) investigate the characteristics of each fiber class using length, diameter, and medulla (i.e., the innermost hair layer) and (3) determine which fiber class is most suitable for the textile industry. Fiber samples were obtained from the mid-torso of 32 Arabian Peninsula camels of different types. Five crimp categories were identified (straight, C-shaped, wavy, ringed, and kinky). Across all crimp categories, the average length ranged from 20.20 – 43.93 mm whereas the mean fiber diameter ranged from 29.74 – 72.11 μm. Percent medullation extended from 68% to 100% with noticeable variation between crimp categories. Overall, fiber traits significantly differed between the crimp categories. Kinky hair was particularly distinct from the other crimp categories. The kinky crimp category is the most suitable dromedary fiber for the textile industry because its fibers are long, fine, and has the lowest percentage of medullated fibers. Hence, we recommend that selective breeding programs and genetic studies focus on the production of dromedaries with kinky hair fibers.

Variation in partial direct costs of dry cow therapy on 37 large dairy herds

The objective of this observational study was to estimate partial direct costs of dry cow antibiotic therapy (DCT) protocols used on 37 large dairy herds in Wisconsin and to estimate the potential monetary savings and reduction in antimicrobial usage (AMU) if selective DCT was used. Partial direct costs of DCT were calculated using costs of intramammary (IMM) antimicrobials and teat sealants. Data were retrospectively collected on 37 large dairy farms for a period of one year and included the total number of cows dried-off, types of IMM antimicrobial used, and product prices (obtained from farm invoices). A single farm visit was performed to verify data. Clinical mastitis (CM) and SCC history across lactation were used as the criteria to identify cows eligible to receive only teat sealants (no antibiotic DCT) based on adoption of a hypothetical selective DCT program. Descriptive statistics were performed using PROC MEANS to summarize continuous herd and cow characteristics. Differences in costs among IMM antibiotic products and eligibility to not receive antibiotics at dry off by parity were analyzed using ANOVA. Differences in milk yield at the last test day and DIM at dry-off based on eligibility for selective DCT were analyzed using PROC MIXED. A total of 35,691 cows were dried-off across all herds (n = 37) and most of the herds used IMM antibiotic DCT at dry-off in most of the cows. Teat sealant was used as part of the dry-off protocol in all but 3 herds. Of the enrolled farms, 30 used blanket antibiotic DCT in all quarters of all cows and 7 herds used selective DCT with no administration of antibiotics given to 0.8% to 58% of the dry cows within herd. Across all farms, the average cost of products given per dried cow was $19.57 ± 0.64 and ranged from $8.72 to $24.04. As expected, the cost per dried cow was greater ($23.45 ± 0.38) in herds that used higher-cost intramammary antibiotics as compared with herds that used lower-cost intramammary antibiotics ($16.64 ± 0.40). When using an algorithm based on udder health records to hypothetically select cows that would be eligible to receive teat sealants only (no antibiotic DCT), eligibility ranged from 27.3% to 93.3% within-herds and varied by parity, milk yield at last test day, and DIM at dry-off. If a selective DCT program based on udder health records was used, an overall reduction of $5.37 (27% of total costs) per dry cow would be expected. Likewise, adoption of selective DCT based on udder health records would reduce AMU at dry off by approximately 51%. However, neither of these estimates included potential adverse health complications (such as increased clinical mastitis) that can occur if selective DCT programs are not effectively performed. Variations in partial direct costs at dry-off were observed among herds based on treatment protocols. In herds that have good udder health management and contagious mastitis pathogens controlled, adoption of selective DCT based on SCC and history of clinical mastitis can reduce AMU and partial direct costs of dry cow management.

The Returns to STEM Programs for Less-Prepared Students

The returns to selective STEM programs depend on whether students complete these programs, earnings conditional on completion, and counterfactual schooling choices. Much research has focused on only one of these margins, potentially leading to an incomplete picture of the returns to STEM education for students with less academic preparation. Using data from a Colombian university and two empirical strategies, we find less-prepared students have higher earnings returns to selective STEM programs than more-prepared students, even though they are less likely to complete these programs. A key mechanism is that less-prepared students have lower-paying counterfactual schooling options. (JEL I23, I26, J24, J31, O15)

TESTING OF WHEAT GENOTYPES FOR SALT TOLERANCE AND LEAF RUST DISEASE CAUSED BY PUCCINIA

Parameters that show a significant genotypic variation and are associated with salt tolerance may be used as rapid and economic screening criteria in breeding programs. The objective of this study was to test growth and yield components for evaluating the salt tolerance of wheat genotypes. Five genotypes of winter wheat (Triticum aestivum L.) were used in this study, that differ from their salt tolerance, which were grown in 28 dS/m saline soil, and irrigated by well water with a salinity 7.5 dS/m. The results showed that salt concentration in the soil was reduced with plant growth stages from 28 dS/m before sowing to 8, 7.5, and 7.6 dS/m for N1, N2, and N3 genotypes, respectively. Whereas approached 16 and 17 dS/m for Tumos2 and Mexipak, cultivars, respectively, at the maturity stage. Concerning germination percentage under saline conditions, wheat genotypes N1, N2, and N3 showed the highest percentages of 89, 90, and 90%, respectively, which was significantly different than wheat cultivars Tumos2 and Mexipak 79 and 83%, respectively. Statistical analysis of the data revealed that genotype N2 required a maximum days for germination 14 days, whereas cultivarTumos2 required less days for germination 12 days. For spikes formation duration growth the genotype N3 was the late 119 days, whereas for physiological maturity N1 genotype was the latest 153 days. The number of spikes per 6 m2, grains spike-1, and grain weight were reduced significantly in sensitive cultivars Tumos2 and Mexipak. Higher grain yield with N2 genotype 2739.43 g with no significant differences with the genotypes N1 and N2, and with significant differences with the rest sensitive cultivars Tumos2 and Mexipak 346.61 and 242.98 g, respectively. Therefore, we conclude that the measurements of growth and yield components may be effective criteria for screening wheat genotypes for salt tolerance. Moreover, N1, N2, and N3 genotypes were identified as the most salt-tolerant genotypes in this study, they can be utilized through appropriate selection and breeding programs for further improvement in salt tolerance of Iraqi wheat genotypes.

Survival Analysis up to 8 Years of 304 Anatomic-Contour Implant Zirconia Crowns Fabricated with a Fully Digital Cast-Free Workflow and Directly Screwed on External Hexagonal Implant Connections without the Interposition of a Ti-Base: A Multicentric Retrospective Study.

Data on the clinical performance of monolithic Zirconia screw-retained crowns on external hexagon implants fabricated from digital scans through a cast-free, fully digital workflow is lacking and needs to be included. This retrospective multicentric study aimed to evaluate the real-life clinical results of monolithic Zirconia screw-retained crowns without the interposition of a Ti-base on external hexagon implants fabricated from intraoral scans and a cast-free approach in private practices. Single external hex implant fixtures were restored with monolithic zirconia crowns without the interposition of a Tibase. The crowns were directly screwed on external hexagonal implant connections with a castfree, fully digital workflow. Data were analyzed using descriptive statistics and the Kaplan- Meier test. Between September 2022 and March 2023, the California Dental Association modified criteria were adopted for clinical evaluation after recalling all patients. A total of 304 single tooth restorations in the maxillary and mandibular posterior regions fabricated between July 2014 and July 2022 in 252 patients (120 males and 132 females, mean age 53.6 years, SD 23.3). Seven crowns were excluded because of patient dropout. The most common minor technical complications were screw loosening (3 crowns) and loss of the screw-access hole filling (3 crowns). Four failures included two implant failures with mobility and two fractured crowns. No screw or implant fractures were recorded. The overall cumulative survival rate was 98.6% and the average success rate (crowns experiencing no failures or complications) was 96.0%. The mean overall survival time was 101.3 months (standard error, 0.847; 95% confidence interval for the mean, 99.67-102.99). The overall survival probability was 87.9% up to 97 months. With careful case selection and comprehensive periodontal maintenance program, single crowns directly screwed onto an external hexagon platform have shown to have excellent survival and success (complication-free) rates, comparable to available data regarding single crowns with a metal implant- prosthetic interface.

Geographic Location and Corporate Ownership of Hospitals in Relation to Unfilled Positions in the 2023 Emergency Medicine Match.

In the 2023 National Resident Matching Program (NRMP) match, there were 554 unfilled emergency medicine (EM) positions before the Supplemental Offer and Acceptance Program (SOAP). We sought to describe features of EM programs that participated in the match and the association between select program characteristics and unfilled positions. The primary outcome measures included the proportion of positions filled in relation to state and population density, hospital ownership type, and physician employment model. Secondary outcome measures included comparing program-specific attributes between filled and unfilled programs, including original accreditation type, year of original accreditation, the total number of approved training positions, length of training, urban-rural designation, hospital size by number of beds, resident-to-bed ratio, and the percentage of disproportionate share patients seen. The NRMP Match had 276 unique participating EM programs with 554 unfilled positions. Six states offered 52% of the total NRMP positions available. Five states were associated with two-thirds of the unfilled positions. Public hospitals had a statistically significant higher match rate (88%) when compared to non-profit and for-profit hospitals, which had match rates of 80% and 75%, respectively (P < 0.001). Programs with faculty employed by a health system had the highest match rate of 87%, followed by clinician partnerships at 79% and private equity groups at 68% (P < 0.001 overall and between all subgroups). The 2023 match in EM saw increased rates in the number of residency positions and programs that did not fill before the SOAP. Public hospitals had higher match rates than for-profit or non-profit hospitals. Residency programs that employed academic faculty through the hospital or health system were associated with higher match rates.

Resistance of juvenile Nile tilapia Oreochromis niloticus from Brazilian populations to Streptococcus agalactiae (serotype Ib and ST-NT)

Nile tilapia is the main farmed fish in Brazilian aquaculture. Streptococcus agalactiae (GBS) is responsible for high mortality rates in fish farms. Genetic improvement is considered an effective alternative for producing resistant animals in aquaculture. The objective of this study was to estimate genetic parameters for resistance to GBS infection in a breeding population of Nile tilapia from Brazil, based on disease challenge using a circulating serotype (Ib and ST-NT). Furthermore, genetic correlations between resistance to GBS and average daily gain (ADG) were estimated to determine whether these traits can be included in selective breeding programs. Survival (SS) and time until death (TD) were the evaluated traits. The survival of the most resistant families was approximately 30%, indicating high phenotypic variation in resistance to the infection. Low to moderate heritability values for resistance traits in the Nile tilapia population were estimated, ranging from 0.14 to 0.27. Heritability for ADG was moderate to high (0.40) based on a growth trial involving 43 families (735 animals). Phenotypic correlations between the resistance traits (SS and TD) and ADG were positive and low, ranging from 0.09 to 0.18, whereas genetic correlations were close to zero. Phenotypic and genetic correlations between SS and TD were considered high and positive, ranging from 0.38 to 0.72. The results suggest that selection for resistance against GBS does not negatively affect juvenile weight gain in Nile tilapia.

Unique features of β-cell metabolism are lost in type 2 diabetes.

Pancreatic β cells play an essential role in the control of systemic glucose homeostasis as they sense blood glucose levels and respond by secreting insulin. Upon stimulating glucose uptake in insulin-sensitive tissues post-prandially, this anabolic hormone restores blood glucose levels to pre-prandial levels. Maintaining physiological glucose levels thus relies on proper β-cell function. To fulfill this highly specialized nutrient sensor role, β cells have evolved a unique genetic program that shapes its distinct cellular metabolism. In this review, the unique genetic and metabolic features of β cells will be outlined, including their alterations in type 2 diabetes (T2D). β cells selectively express a set of genes in a cell type-specific manner; for instance, the glucose activating hexokinase IV enzyme or Glucokinase (GCK), whereas other genes are selectively "disallowed", including lactate dehydrogenase A (LDHA) and monocarboxylate transporter 1 (MCT1). This selective gene program equips β cells with a unique metabolic apparatus to ensure that nutrient metabolism is coupled to appropriate insulin secretion, thereby avoiding hyperglycemia, as well as life-threatening hypoglycemia. Unlike most cell types, β cells exhibit specialized bioenergetic features, including supply-driven rather than demand-driven metabolism and a high basal mitochondrial proton leak respiration. The understanding of these unique genetically programmed metabolic features and their alterations that lead to β-cell dysfunction is crucial for a comprehensive understanding of T2D pathophysiology and the development of innovative therapeutic approaches for T2D patients.

Identification of candidate genes associated with growth and development of sheep from a crossbred population using genome-wide association studies

The article presents the results of a search for genome-wide associations with phenotypic traits characterizing the growth and development of sheep from a crossbred population obtained from crossing Romanov sheep and F1 hybrid rams (Romanov sheep x Katahdin). The phenotype database included ten body measurements (withers height, sacral height, back height, chest depth, chest width, ischial tuberosity width, body length, oblique body length, chest girth, pastern girth) recorded at the age of 6 days, 3, 6 and 9 months. Genotyping of sheep was carried out using high-density DNA chips containing about 600,000 SNP markers. Genome-wide association studies (GWAS) were performed using regression analysis in the STATISTICA 10 program. The search for candidate genes localized in the SNP region was performed using Ensembl genome browser 110. There was carried out an analysis of the matches of the identified SNPs with known quantitative trait loci (QTLs) described in the Sheep Quantitative Trait Locus Database. There were found SNPs that were significantly associated with the studied phenotypic traits overlapped with the QTLs, among which the most common categories were “Body weight (slaughter)”, “Muscle weight in carcass”, “Body weight (live)” and “Bone weight in carcass”. There has been established that SNPs significantly associated with exterior traits were localized within or in the immediate vicinity of 64 genes. There were found potential candidates regulating the growth of muscle (FOXO3, PRKAG3, MYOZ2, and ANKRD1) and cartilage tissues FGF12) and involved in metabolic processes, which were critical for the growth of lambs (CLDN, ALB, and MRC1). Along with the known in sheep functional candidates (CAST and SCD5) , there were identified genes that were not previously described in sheep, but regulated growth and development processes in other livestock species including genes RAB28, PRKAG3 and FOXO3. The identified SNPs can be recommended for inclusion in marker-guided selection programs in sheep breeding.

Comparative analysis on growth performance, survival and harvest traits between offspring from wild and mass-selected populations of Crassostrea nippona

Crassostrea nippona has recently been recognized as a preferred alternative to C. gigas in summer due to its firm flesh and high glycogen content. To promote industrial development, the mass selective breeding program was initiated to improve growth performance of C. nippona in 2014. Although a steady genetic gain of approximately 10% for growth traits was achieved in each of the first three generations of the selected strains, little is known about the cumulative genetic progress in desired traits contributed by the selective breeding in the genetic improvement program. In this study, the aquaculture performance of the selected population was comprehensively evaluated by comparing the production performance and reproductive traits of the progeny (WF1 and SF4) from the wild population and the third-generation selected line in commercial farming environments. The results showed that the diameters of eggs from both populations were at similar levels, but the fertilization and hatching rates of the progeny from the selected lines were significantly higher than those of the wild population (P < 0.05). At larval stages, the shell height and cumulative survival rate (CSR) of individuals from SF4 were consistently superior to that of WF1, especially on day 6 post-fertilization, in which CSR of the improved C. nippona was increased by 25.08% compared to that of wild oysters. Meanwhile, a significant 12.10% enhancement in the metamorphosis rate was observed in SF4 when compared with WF1. During the grow-out stage, SF4 displayed distinct advantages in growth performance and survival compared to the wild strain, with 23.19, 33.48, 34.18 and 79.11% improvement in shell height, body weight, CSR and final yield at harvest on day 800, respectively. Meanwhile, relative brood amount (RBA) associated with initial development of offspring was found to be significantly higher in SF4 compared with WF1 (P < 0.05). Remarkably, the gonadal development, sex ratios and biochemical composition of oysters from both populations were at similar levels at final harvest, implying that high-intensity artificial selection had no significant effect on reproductive characteristics and nutritional quality of C. nippona. The encouraging results in the present study suggest that the overall genetic progress contributed by genetic breeding is considerable in the fast-growing strain of C. nippona, and such gains are expected to continue to increase with further selective breeding.

Genetic diversity of common carp Cyprinus carpio in the base population of a selective breeding programme in India

A selective breeding program for developing a suitable strain of Cyprinus carpio (Linnaeus, 1758) for inland saline aquaculture in India is in progress. At ICAR-CIFE, various geographical populations of common carp of India, viz. Madhya Pradesh (MP), Haryana (HR), Tripura (TR), Andhra Pradesh (AP), Manipur (MN), and Maharashtra (MH) formed the base population for selective breeding. The present study assesses the genetic diversity of these stocks using truss morphometry and mitochondrial DNA D loop marker analysis. The images of 600 fish were captured and digitized. The landmarks were identified, and an image network was constructed for truss analysis using tpsDig2 and PAST software. The data was subjected to scale transformation and factor analysis using SAS for Academics. The top 3 factors could explain 85.40% of the total variation. The results indicate stock-wise and sex-wise groupings. The mitochondrial DNA (D-loop) sequence analysis was conducted on 169 samples using MEGA6 software. The overall average haplotype and nucleotide diversity of the population were 0.08129 and 0.01134, respectively. Among stocks, the MP stock had a maximum of four haplotypes. The AMOVA results reveal that the stock AP is unique, and the other stocks form a single grouping. The information generated from the present study delineates genetic diversity among stocks and will aid in designing breeding plans.

The impact of parents' stress on parents' and young childrens' mental health-Short- and long-term effects of risk and resilience factors in families with children aged 0-3 in a representative sample.

Stress in parents has a significant impact on parenting and infant's development. However, few studies have examined cross-sectional and longitudinal links on risk and resilience of burdened families. Thus, this study aimed to investigate subjective risk and resilience factors on family well-being. Data stem from the 2015 nationwide study "Children in Germany" ("Kinder in Deutschland" - KiD 0-3). Parents of children aged zero to 3years (N=8.063) were recruited from random probability-sampled paediatric clinics (n=271) across Germany. Risk and resilience variables such as parents' perceived stress (PSS-4), competence, isolation and attachment (PSI), as well as parental inner anger (items from CAP), relationship quality (DAS-4) and the child's negative emotionality (items from SGKS) were assessed at baseline in addition to demographic variables to predict parents' mental health (PHQ-4) and negative emotionality of the child at baseline (T1) and in the 2-year follow-up (T2) using linear regression models. At baseline, parents' mental health was predicted by inner anger, the child's negative emotionality and being a single parent (R2=45.1%) at baseline, but only by parenting competence at the two-year-follow-up (R2=25.1%). The child's negative emotionality was predicted (R2=27.5%) by the child's age, and parental inner anger and competence, attachment, perceived stress, mental health as well as education background. At two-year-follow-up, the child's age, single parenthood, social welfare benefit, child's negative emotionality at baseline, relationship quality and competence were significant predictor variables (R2=22.8%). This study highlights the impact of specific risk and resilience factors not only on parents' mental health but also the child's negative emotionality in the short and long-term in early childhood. Universal, but also selective prevention programs should increase parents' resilience (e.g., focusing on self-efficacy, competence, coping strategies).

Farmers’ Perception on Contribution of Community-Based Breeding Program to Sheep Flock Performance and Income of Producers in Hula and Dara Districts, Southern Ethiopia

Community-based breeding programs (CBBP) have been viewed as attractive breeding strategies, resulting in significant improvements in the performance of small ruminants and the income of producers in many parts of the world. As part of these interventions, a community-based breeding program was implemented on Abera sheep mostly reared in the region since 2013. An interview was conducted with 188 sheep producers (91 CBBP members) and 97 non-CBBP members) to know the contribution of CBBP in terms of sheep flock performance improvement and income of sheep producers in the Hula and Dara districts of Sidama region. Focused group discussions with 6–8 individuals in each breeder cooperative were separately made to complement the survey results. CBBP households owned significantly (p&lt;0.05) larger sheep heads (7.28 versus 4.99) than non-CBBP members. CBBP households further had more market participation, sold significantly (p&lt;0.05) higher average sheep (2.4 versus 1.3), and consequently earned significantly (p&lt;0.05) higher annual income (ETB 3877) than non-participating (ETB 2007) households. The majority of CBBP households (85%) observed a better twining rate for their sheep flocks since they joined the breeding program. The average age of 8.63 months of a lambing interval, 7.9 months of ram maturity for breeding, and 10.42 months needed for a ram to achieve market age before implementation of the breeding program were significantly (p&lt;0.05) reduced to 7.31 months, 6.2 months, and 7.69 months, respectively, after sheep producers started a selective breeding program. Low market integration (0.28), sheep mortality (0.21), feed shortage (0.20), low institutional support and coordination (0.17), and managerial problems of the committee (0.13) were major problems with the ranking index in parenthesis. Despite the significant contribution of the breeding program to sheep producers, the current study found weak and unsustainable institutional support for proper breeding ..........

Genotypic Variability, Correlation and Path Coefficient Analysis for Elite Genotypes of Chickpea (Cicer arietinum L.)

The study was conducted during the rabi season (October, 2021–April, 2022) at the Crop Research Centre, Department of Genetics and Plant Breeding, School of Agriculture, ITM University, Gwalior, Madhya Pradesh, focused on 30 chickpea genotypes to evaluate genetic variability, heritability, genetic advance, correlations and path analysis among quantitative traits. Utilizing a randomized block design, the study found that the number of pods plant-1 exhibited the highest variability, while pod length showed the least variability. Significant phenotypic and genotypic coefficients of variation highlighted substantial variability among the genotypes, with shoot length, root length, and the number of secondary branches displaying high genetic advance and heritability. This suggested the predominant influence of additive gene action on these traits, making them suitable for selection-based improvements. Genotypic and phenotypic correlations were generally similar, indicating minimal environmental influence on most traits. Positive correlations were identified between the number of primary branches, number of secondary branches, pods plant-1, seeds pod-1, seed index and other dependent traits, indicating their potential for enhancing crop yield through selection. The study further revealed significant direct associations among traits, emphasizing the presence of additive gene action and the feasibility of effective selection for improving chickpea characteristics. In conclusion, the findings offer valuable insights into the genetic variability and heritability of chickpea traits, guiding future breeding and selection programs for enhanced genotypes.

Optimizing variable selection and neighbourhood size in the K-nearest neighbour algorithm

The K-nearest neighbour (KNN) algorithm is one of the well-known classifiers applied in various research areas. The input requirement includes a set of variables, the choice of the neighbourhood size (K) and the distance metric which are typically selected on experimenting with the data. The first two are usually decided sequentially in previous studies. This paper proposes a mixed integer linear program for simultaneous variable selection and determination of neighbourhood size which has not been expored in past research. When ties occur in the variable selection and/or the choice of K, an optimization approach helps search for the best combination of decisions for a given objective. Two distance metrics, Euclidean and Hassanat, are incorporated into the model for comparison. The proposed model adopts accuracy and recall as separate objective functions to determine the best combination of the two decisions in binary classification problems. Computational experiments are designed with ten publicly available datasets. Results from the proposed models are compared with the ensemble approach KNN using Hassanat distance. Three larger problems are also tested with the optimal K generated by the model. An effective set of variables and neighbourhood size decided by optimization can facilitate solving classification problems. Model limitations are also discussed.

Genetic dissection of green pod yield in dolichos bean, an orphan vegetable legume, using new molecular markers.

In the era of genomic-assisted breeding for crop improvement, developing new molecular markers and validating them for use in breeding programs are the prelude. Dolichos bean is one of the most important vegetable legume crops owing to its nutrient-rich green pods used as vegetables. Limitations in genomic resources, including molecular markers, restrict the accelerated improvement of the crop. In the present investigation, a set of 430 new simple sequence repeat markers was developed from sequence information of a reference variety. These markers included di- and tri-nucleotide repeats. The markers were assayed on an association panel, which was evaluated for green pod yield over 5years. A multi-locus model, FarmCPU, was used to assess the marker-trait association analysis. A total of 106 marker-trait associations were identified using an efficient mixed-model approach. Tri-nucleotide repeats were more informative and predominantly associated with trait. Among these markers, 17 were associated with a high level of significance. Markers LP-D-68 and LP-D-14 were identified with a high level of significance in 5-year pooled data and explained 12.70% and 12% of the phenotypic variance, respectively. These markers associated with a high level of confidence have significant scope for use in marker-assisted selection programmes. Other associated markers may be utilized for improving parents through marker-assisted recurrent selection or genomic selection programs.