This feeding experiment was performed to determine the effect of gradually increasing substitution of compound feed with whole-plant corn silage co-fermented with bacteria and enzymes (WPCS-BE) on the growth performance, slaughter performance and serum parameters of geese. A total of 180 35 d old healthy female Taizhou geese were distributed into six groups and fed the compound feed (control group), and the experimental groups (groups I, II, III, IV and V) were fed diets in which the WPCS-BE replaced 10%, 20%, 30%, 40% and 50% of the compound feed for 49 days. The BW of the geese in group III was increased from 56 to 63 d of age. The ADG of groups II, III and IV was improved during the age of 42-70 d (P < 0.05). At 42-91 d of age, the ADFI and F/G increased significantly with the proportion of WPCS-BE in each experimental group. The geese in group IV had a higher slaughter yield than that of the other groups at 91 d of age (P < 0.05). At 70 d of age, the relative weight of the liver in group V and the relative weight of the gizzards of groups III, IV and V were significantly increased (P < 0.05). At 91 d of age, the relative weight of the liver in groups IV and V and the relative weight of the spleen of group III were significantly higher than those of the control group (P < 0.05). There were no significant differences in the concentration of albumin, alkaline phosphatase, blood urea nitrogen, glucose or total protein among all groups at 70 and 90 d of age (P > 0.05). Under these experimental conditions, it is recommend that the substitution level of WPCS-BE should be 20%-30%, which can improve the growth performance of Taizhou geese and has no negative effect on the slaughter performance or serum parameters.

Trichomonadida are flagellated protozoa that infect a wide range of vertebrate species, including poultry such as Gallus gallus domesticus. These pathogens hold significant veterinary importance due to their role in the emergence of diseases that can severely reduce productivity and cause substantial financial losses. Traditional methods for identifying these protozoa are limited by the subtle morphological variations between species. Molecular studies on Trichomonadida species in North African poultry are scarce. This study is the first to investigate the genetic diversity and phylogenetic relationships of Trichomonadida species in Tunisian poultry farms using a multilocus molecular approach (18S rRNA and α-actinin1), providing valuable insights into their epidemiology. Based on the analysis of 18S rRNA sequences, the Tunisian samples were divided into four main clades. The first clade, identified as H. meleagridis, was detected in caecal samples and genomic DNA of H. gallinarum nematodes from ten Tunisian localities. This clade was further subdivided into two distinct clusters, designated genotype 1 and genotype 2. Analysis of both nuclear markers revealed that all Tunisian haplotypes clustered with those from France, belonging to genotype 2, with a genetic distance of 4% (18S rRNA) between the two clusters. Furthermore, the analysis revealed the coexistence of H. meleagridis and P. wenrichi protozoa infecting H. gallinarum, suggesting a potential mixed infection. Additionally, other Trichomonadida species, including Simplicomonas sp. and T. gallinarum, were detected in the caecal samples. Phylogenetic analysis (ML) demonstrated a close genetic relationship between H. meleagridis and P. wenrichi, as well as between Simplicomonas sp. and the Monoceromonas-Tritrichomonas group. Both genotypes 1 and 2 of H. meleagridis exhibited a sister-group relationship with P. wenrichi, suggesting a shared evolutionary origin. This study represents the first investigation into the genetic diversity of Trichomonadida species in Tunisian poultry, highlighting the utility of the 18S rRNA locus for evaluating genetic variation and identifying potential mixed infections.

The introduction of the Montbeliarde dairy breed in Ecuador started in the 1990s with the objective of improving the production performance of other dairy breeds. The objective of this study was to analyze the population structure, inbreeding and genetic diversity of the Montbeliarde breed using official pedigree information from the Montbeliarde Association of Ecuador. The total population included 1,584 females and 210 males. Three databases were considered: historical (all individuals= 1,794), current (individuals born between 2011-2021= 896) and reference (individuals with known sire and dam within the current population= 857). Population structure variables were: pedigree completeness index (PCI), number of equivalent (GEq), complete (GCom) and maximum (GMax) generations and generation interval (GI). DG variables were: inbreeding (F), inbreeding increment (ΔF), average relatedness (AR), co-ancestry (C), Non-random mating (α), effective population size (Ne) and genetic conservation index (GCI). The gene origin probability variables were: number of founders (f), effective number of founders (fe) and ancestors (fa), number of equivalent genomes (fg), fe/fa and fg/fa ratio and DG losses. The databases were analyzed by ENDOG and POPREP software. PCI in the historical population compared to the current population increased from 89.1 to 96.7% (sire pathway) and from 48.5 to 53.4% (dam pathway) while the GI increased from 7.2 to 7.9 years in the historical and current population, respectively. Moreover, F=1.53%, AR=2.91%, ΔF= 0.14%, C= 1.46%, α=-0.0094; GCI=3.65, and Ne= 56 (2014) values were obtained. Gene origin probability in the reference population was f=372, fa=35, fe=121.71, fg=38.06, fg/fe=0.31 showing a GD loss due to unequal contribution of founders (0.41%) and bottleneck and genetic drift (1.31%). In conclusion, the Ecuadorian Montbelarde cattle population displayed a relatively low diversity and quite high genetic relationship. Inbreeding level of the population increased over time. The introduction of new purebred bloodlines is important to minimize the inbreeding levels ensuring the long-term conservation of this breed to prevent the GD loss.

The Brown Swiss cattle is the second most important dairy breed in Ecuador. Genetic improvement programs require monitoring population structure and genetic diversity (GD) over time. The objective was to analyze the current structure and GD of the Brown Swiss breed in Ecuador. The genealogical database of the Ecuadorian Brown Swiss Association, with 30,332 females and 5,846 males was used. Three databases were designed: historical (all individuals= 36,178), current (individuals born between 2014-2023= 3,698) and reference (individuals with known sire and dam within the current population= 3,016). Population variables: pedigree completeness index (PCI), number of equivalent (GEq), complete (GCom) and maximum (GMax) generations and generation interval (GI). DG variables: inbreeding (F), inbreeding increment (ΔF), average relatedness (AR), co-ancestry (C), Non-random mating (α), effective population size (Ne) and genetic conservation index (GCI). The gene origin probability variables: number of founders (f), effective number of founders (fe) and ancestors (fa), number of equivalent genomes (fg), fe/fa and fg/fa ratio and DG losses. The databases were analyzed by ENDOG and POPREP software. PCI in the historical population ranged between 68.0-16.3% and between 81.7-63.9% in the current population (1st to 6th generation, respectively). GEq in the current population was 2.61 while the GI decreased from 6.85 to 5.70 years in the historical (n=10,655) and current (n=1,582) population, respectively. In addition, F=2.35%, AR=2.23%, ΔF= 0.41%, C= 1.12%, α=0.0125; GCI=10.41, and Ne= 120 (2015-2020) values were observed. Gene origin probability in the reference population was f=1,384, fa=40, fe=157.60, fg=24.86, fg/fe=0.16 showing an important GD loss (2.01%) due to unequal contribution of founders (0.32%) and bottleneck and genetic drift (2.01%). In conclusion, despite the slight reduction of GI and low F, ΔF, Ne and AR values, an important GD loss showed the urgent need for optimal management of mating schemes when using closely related individuals.

Introduction

The liquid chip based on Genotyping by Target Sequencing (GBTS) technology can detect a wide range of variations (e.g., SNPs, InDels) and offers high efficiency, low cost, broad adaptability, and flexible application. Reproductive traits are crucial functional traits in dairy cows. Intense selection for milk production traits, coupled with the negative genetic correlation between reproductive and milk production traits, has led to a decline in reproductive performance, decreased reproductive rates, increased veterinary treatment rates, and higher culling rates. Given the low heritability of reproductive traits, exploring genomic selection methods to enhance the accuracy of reproductive trait predictions is significant. This study estimates genetic parameters and performs weighted single-step genome-wide association studies (wssGWAS) to identify the genes associated with three fertility traits in the Chinese Holstein population: the number of services for heifers (NS_H), the interval from calving to first service (ICF), and the calving interval (CI).

Materials and Methods

The phenotypic records for NS_H, ICF, and CI were 134,141, 345,751, and 238,277, respectively. A total of 5,545 cattle had liquid chips (166,009 SNPs + 7,518 InDels), while 18,226 had 150K chips, which were imputed at the liquid-phase chip level and merged after quality control. Genotype data for 13,690 individuals across 103,262 loci were analyzed. An animal model was used for NS_H, while ICF and CI employed a repeatability model. A weighted single-step genome-wide association method with 20 adjacent SNPs as sliding windows was implemented.

Results

The heritability estimates for NS_H, ICF, and CI were 0.049, 0.029, and 0.064, respectively. Ten window regions associated with fertility traits were identified across seven chromosomes, with candidate genes including OVOS2, TESK1, and HSPA14.

Conclusion

These findings provide a foundation for future research into the genetic mechanisms underlying fertility traits, contributing to accurate genomic predictions in the Chinese Holstein population.

INTRODUCTION: Ovarian tissue vitrification is an alternative for the preservation of germplasm banks in animals with high zootechnical value. However, despite its efficacy, the technique has some limitations due to the high cytotoxicity of cryoprotectants, which cause damage to ovarian follicles. One of the mechanisms involved in this damage is oxidative stress, characterized by an imbalance between free radicals and antioxidant enzymes such as SOD. Therefore, this study aimed to evaluate the potential of Punica granatum, a well-known potent antioxidant, during the vitrification of bovine ovarian tissue on Superoxide dismutase (SOD) gene expression. METHODOLOGY: To this, fragments of bovine ovarian cortex were vitrified with 10 µg/mL of ethanolic extract from Punica granatum (EE-PG) and stored in liquid nitrogen for 5 days. After warming, the tissues were incubated for 24 hours to assess the resumption of cellular metabolism and subsequently stored at -80°C for qPCR analysis. RESULTS: There was no significant difference when comparing the use of 10 µg/mL of EE-PG with the fresh control and vitrified control groups. This indicates that the EE-PG maintained SOD expression levels. SOD is an enzyme responsible for the first line of cellular antioxidant defense. It catalyzes the conversion of the superoxide anion into a less harmful product, hydrogen peroxide, which possibly contributes to reducing damage and preserving follicular structures. CONCLUSION: In summary, the addition of 10 µg/mL of EE-PG to the vitrification solution maintains SOD expression in vitrified bovine ovarian tissue, making it a promising alternative for preserving reproductive potential.

Freshwater habitats are affected by prevalent pollutants, like polycyclic aromatic hydrocarbons (PAHs), and by increasing temperatures due to global warming. Monolayer (2D) cultures of fish cell lines like the liver-derived RTL-W1 are commonly used to investigate toxicological effects. However, 3D systems reproduce more efficiently in vivo responses and may be more valuable in ecotoxicological research.

An RTL-W1 3D model (60,000 cells/well) was generated using 96-well ultra-low attachment (ULA) plates. Mature, 10-day-old spheroids were exposed to control, solvent control (0.1% DMSO), and 10 nM and 100 nM of benzo[k]fluoranthene (BkF) at 18 ºC and 23 ºC. After a 4-day exposure, spheroids were assessed for viability (lactate dehydrogenase (LDH) and Alamar Blue assays), biometry, histology (optical and electron microscopy), and mRNA expression of target genes related to xenobiotic metabolism (cytochrome P450 (CYP)1A, CYP3A27, aryl hydrocarbon receptor (AhR), glutathione S-transferase (GST), uridine diphosphate–glucuronosyltransferase (UGT), catalase (CAT), multidrug resistance-associated protein 2 (MRP2) and bile salt export protein (BSEP). Protein expression of CYP1A was also assessed by immunocytochemistry (ICC).

Temperature and BkF exposure did not alter the spheroids’ viability or biometry. Nevertheless, in electron microscopy, more aspects of cell degeneration were noticed at 23 ºC. CYP1A expression increased in both BkF conditions and AhR only in the higher concentration. Regarding UGT, temperature and BkF interactively modelled its expression, which markedly increased in the 100 nM condition at 23 ºC. In contrast, CYP3A27, MRP2, and BSEP expression were lower at 23 ºC. CAT and GST were not affected by temperature or BkF. ICC for CYP1A showed a dose-dependent increase.

The results suggest that RTL-W1 spheroids may be a handy novel model for in vitro research on liver effects of BkF/PAHs and temperature, namely on detoxifying genes.

Funding: Master Degree in Environmental Contamination and Toxicology, U.Porto; FCT strategic funding UIDB/04423/2020 and UIDP/04423/2020 to CIIMAR/CIMAR.

The objective of this work was to use the approximate probabilities computed by iterative peeling to include genotype information at the FecX^bar/BMP15 major gene in a prolific line of Barbarine sheep, of which a few animals were genotyped. This line is raised at the experimental station of the Tunisian National Institute for Agronomic Research (INRAT) and a selection program for prolificacy has been carried out since 1979. The FecXbar/BMP15 mutation responsible for prolificacy and ovulation rate was identified, but this information is not considered in the actual selection program of this line. Data consisted of 2794 litter size (LS) records of 1014 females from 1989 to 2019 and 4372 animals in the pedigree. Probabilities for each possible Fec/X^bar genotype for animals with unknown genotypes were estimated based on iterative peeling equations using the Alphapeel software. Then, heritability (h²) and estimated breeding values (EBVs) were calculated with two models: i) a classic model without genotype information, and ii) a model including the imputed genotypes as a fixed effect. All parameters were estimated using the Gibbs sampling methodology as implemented in the TM software, and LS was modeled as a discrete variable. h² was estimated as 0.14 for both models. The correlation between estimated breeding values in both models was 0.99. These results indicate that including FecXbar/BMP15 has no impact on the genetic evaluation for this prolific line. Nevertheless, further work on genotyping a larger number of animals will be required.

Lactoferrin (LF) is an iron-binding glycoprotein essential to the mammalian innate immune system. Its concentration varies significantly across species and lactation stages. Camel milk contains substantially higher levels of LF compared to bovine milk.

The Camelus dromedarius lactoferrin gene is structured in 17 exons and 16 introns. However, there is no available information on interspersed repeated elements, or retrotransposons. These elements are valuable genetic markers and offer insights into phylogenetic relationships, population structure, and evolutionary processes.

This study aims to identify and characterize interspersed repeated elements within the dromedary lactoferrin gene using the Repeat Masker bioinformatic tool.

A total of 20 elements were identified, including 6 SINEs, 11 LINEs, 1 LTR, and 2 hAT-Charlie/DNA elements. Short interspersed repeat elements were dispersed in introns 1, 13, and 15, while long interspersed elements spread over introns 1, 2, 6, 9, 10, 13, 14, and 16. hAT-Charlie/DNA elements were found in introns 2 and 16, while long terminal repeats were located in intron 12. A comparative analysis with the bovine lactoferrin gene revealed that the latter contains a higher number of interspersed repeated elements (33), 9 of which were SINEs and 18 of which were LINES, 2 long terminal repeats, and 4 hAT-Charlie/DNA. This variation may be due to potential differences in evolutionary history or regulatory mechanisms.

Conformation traits are very important in the Pura Raza Español (PRE) horse. Although most of them have medium to high heritability, there is a great interest in obtaining highly reliable estimates of heritabilities. The objective of this study was to estimate the heritabilities (h²) of conformation traits in PRE horses with three different approaches. The dataset consisted of 7152 morphological records and 41,888 animals in the pedigree, obtained from the Royal National Association of Spanish Horse Breeders (ANCCE). A total of 4057 animals were genotyped with 60,136 SNPs and included in the analysis. Measurements from six zoometric traits were analysed: height at withers (HW), scapular–ischial length (SiL), length of back (LB), dorso-sternal diameter (DsD), thoracic perimeter (TP), and perimeter of anterior cannon bone (PACB). Firstly, heritabilities were estimated with a classical approach with pedigree-based REML and single-step GREML with the HiBlup v1.3.1 software. Then, SNP-based heritabilities were estimated using GREML, accounting for patterns of regional linkage disequilibrium (LD) with the LDAK 5.2 software program. The largest heritability estimates were obtained when we employed REML or ssGREML analysis in this population. Heritabilities were similar for all traits for REML and ssGREML, and their estimates oscillated between 0.33 (0.03) for DSD and PACB and 0.77 (0.035) for HW. Except for HW, the SNP-based heritabilities were smoother than those from REML and ssGREML and they varied between 0.21 (0.03) for DsD and 0.49 (0.031) for SiL. It is also notable that in the LDAK model, the h² estimation improved in most of the analysed traits, which was reflected in the decrease in the standard errors. These results suggested that in the case of these traits where there is high LD, it is necessary to adjust for the LD to correct the overestimation of heritability.