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The widespread use of genome-wide association studies resulted in the discovery of genomic regions associated with fatty acid (FA) composition in different porcine tissues, but little information exists about the genes involved in FA composition of meat obtained from heavy pigs selected for the production of Italian dry-cured hams. To this objective, we genotyped with a single nucleotide polymorphism (SNP) panel 795 Italian Large White heavy pigs to identify the markers and genomic regions associated with Semimembranosus muscle FA profile. Heritability estimates for intramuscular fat FA profile were of low-to-moderate magnitude, suggesting that these traits may be improved with genomic selection. On the whole, 45 SNPs were significantly associated with 14 FAs, and 4 of them (ALGA008109, ALGA0081097, CASI0010164 and SIRI0000267) were associated with more than 1 FA. The palmitoleic : palmitic and oleic : stearic ratios displayed the highest number of significant markers and the most significant associations (Bonferroni adjusted P < 5.00E−07). Of particular interest, the palmitoleic : palmitic ratio was strongly associated with markers located at 111 to 114 Mb on chromosome 14, in the same chromosomal region where Stearoyl-CoA desaturase Δ9 (SCD) gene is located. Several significant chromosomal regions were found; some of them harbour key genes playing pivotal roles in FA desaturation and elongation, such as SCD and some members of the Elongation of Very Long-Chain FA (ELOVL) gene family. The results suggest that the identification of causal mutations in these regions may provide a set of markers useful for selection schemes aimed at improving FA composition in pork products.

Subcutaneous fat thickness and fatty acid composition (FAC) play an important role on seasoning loss and organoleptic characteristics of seasoned hams. Dry-cured ham industry prefers meats with low contents of polyunsaturated fatty acids (PUFA) because these negatively affect fat firmness and ham quality, whereas consumers require higher contents in those fatty acids (FA) for their positive effect on human health. A population of 950 Italian Large White pigs from the Italian National Sib Test Selection Programme was investigated with the aim to estimate heritabilities, genetic and phenotypic correlations of backfat FAC, Semimembranosus muscle intramuscular fat (IMF) content and other carcass traits. The pigs were reared in controlled environmental condition at the same central testing station and were slaughtered at reaching 150 kg live weight. Backfat samples were collected to analyze FAC by gas chromatography. Carcass traits showed heritability levels from 0.087 for estimated carcass lean percentage to 0.361 for hot carcass weight. Heritability values of FA classes were low-to-moderate, all in the range 0.245 for n-3 PUFA to 0.264 for monounsaturated FA (MUFA). Polyunsaturated fatty acids showed a significant genetic correlation with loin thickness (0.128), backfat thickness (−0.124 for backfat measured by Fat-O-Meat’er and −0.175 for backfat measured by calibre) and IMF (−0.102). Obviously, C18:2(n-6) shows similar genetic correlations with the same traits (0.211 with loin thickness, −0.206 with backfat measured by Fat-O-Meat’er, −0.291 with backfat measured by calibre and −0.171 with IMF). Monounsaturated FA, except with the backfat measured by calibre (0.068; P

Longevity is one of the most important traits determining dairy cow profitability. In the last decades dairy cows suffered a lowering in the age at culling. With the aim to identify the genes involved in longevity, dates of birth, yields, dates of calving during lifespan and culling dates were collected for 946 culled cows which had been genotyped with the Bovine High Density panel. Using the GenABEL package in R, genome-wide association analysis was performed on three potential traits of longevity: (1) ‘days in production,’ (2) ‘days in herd,’ (3) number of calvings over lifespan.’ Five genome-wide significant single nucleotide polymorphisms (SNPs) associated with all three longevity traits were detected. Several consecutive SNPs identified on chromosomes 16 and 30 indicated the presence of two suggestive quantitative trait loci (QTL). The genes comprised in the QTL regions had biological functions related to fertility, reproductive disorders, heat stress and welfare of cows. These findings might contribute to improving breeding strategies to improve longevity.

Protected designation of origin dry-cured hams are obtained from heavy pigs (slaughtered at about 160 kg of live weight). A specific breeding program designed to improve meat quality for this production has included as key traits the level of intermuscular fat between the leg muscles and ham weight loss during the seasoning period together with a balance between fat and lean cuts. In this study we carried out genome-wide association studies for seven traits used in the genetic merit of Italian Duroc heavy pigs, five related to meat and carcass quality traits (visible intermuscular fat, ham weight loss at first salting, backfat thickness, ham weight and lean cuts), and two related to performance and efficiency traits (average daily gain and feed : gain ratio). A total of 573 performance-tested pigs were genotyped with the Illumina PorcineSNP60 BeadChip and genome-wide association analyses were carried out using the Bayes B approach with the 1 Mb window option of GenSel and random residuals for each of the seven traits. Detected windows were supported by independent single nucleotide polymorphism analyses with a linear mixed model (LMM) approach on the same animals for the same traits. A total of 30 windows identifying different quantitative trait loci (QTL) were detected and among those, 27 were confirmed by LMM in one of these traits. Among the confirmed windows, three QTL were reported for visible intermuscular fat, seven for ham weight loss at first salting and five and four for backfat thickness and lean cut, respectively. A total of eight QTL were detected for the other production traits. No overlapping QTL were reported except for one window on porcine chromosome 10 between lean cuts and ham weight that contained the CACNB2 gene that has been already associated with loin marbling score in other Duroc pigs. Several regions contained genes that have been already associated with production traits in other pig breeds, including Duroc lines, related to fat deposition or muscle structure. This work reports, for the first time, genome-wide association study results for several traits in Italian Duroc heavy pigs. These results will be useful to dissect the genetic basis for dry-cured ham production traits that determine the total genetic merit index of Italian Duroc pigs.

This study seeks to verify the feasibility of increasing twinning in a herd of the Italian autochtonous Maremmana breed. The data set included 1260 individuals born from 1963 to 2014, 527 males and 733 females, 402 of them calving at least once from 1983 through 2015. Breeding values for twinning were estimated by a single-trait linear animal model. However, since twinning is a dichotomous trait and the frequency of twins is far smaller than the frequency of single births, breeding values were also estimated by a single-trait animal threshold model. Heritability of twinning was 0.014±0.018 and 0.062±0.093 for the linear and the threshold models, respectively. Repeatability was 0.071±0.004 and 0.286± 0.012, respectively, for the two models. Genotyping with the Illumina BovineSNP54 BeadChip was performed for cows living on farm in 2012 (119 cows) and a genome-wide association analysis was performed on the corrected phenotype of all calving during the lifespan of each cow, using the GenABEL package in R and a three step GRAMMAR-GC approach. Genomic heritability, calculated from the genomic kinship matrix estimated through genomic marker data, was 0.29±0.021. The most significant detected single nucleotide polymorphisms (Hapmap22923-BTA-129564) was located in proximity of two genes, ARHGAP8 and TMEM200C, which might be potential functional candidates for twinning rate in cattle.

Genomic selection is becoming a common practise in dairy cattle, but only few works have studied its introduction in pig selection programs. Results described for this species are highly dependent on the considered traits and the specific population structure. This paper aims to simulate the impact of genomic selection in a pig population with a training cohort of performance-tested and slaughtered full sibs. This population is selected for performance, carcass and meat quality traits by full-sib testing of boars. Data were simulated using a forward-in-time simulation process that modeled around 60K single nucleotide polymorphisms and several quantitative trait loci distributed across the 18 porcine autosomes. Data were edited to obtain, for each cycle, 200 sires mated with 800 dams to produce 800 litters of 4 piglets each, two males and two females (needed for the sib test), for a total of 3200 newborns. At each cycle, a subset of 200 litters were sib tested, and 60 boars and 160 sows were selected to replace the same number of culled male and female parents. Simulated selection of boars based on performance test data of their full sibs (one castrated brother and two sisters per boar in 200 litters) lasted for 15 cycles. Genotyping and phenotyping of the three tested sibs (training population) and genotyping of the candidate boars (prediction population) were assumed. Breeding values were calculated for traits with two heritability levels (h2=0.40, carcass traits, and h2=0.10, meat quality parameters) on simulated pedigrees, phenotypes and genotypes. Genomic breeding values, estimated by various models (GBLUP from raw phenotype or using breeding values and single-step models), were compared with the classical BLUP Animal Model predictions in terms of predictive ability. Results obtained for traits with moderate heritability (h2=0.40), similar to the heritability of traits commonly measured within a sib-testing program, did not show any benefit from the introduction of genomic selection. None of the considered genomic models provided improvements in prediction ability of pigs with no recorded phenotype. However, a few advantages were found for traits with low heritability (h2=0.10). These heritability levels are characteristic for meat quality traits recorded after slaughtering or for reproduction or health traits, typically recorded on field and not in performance stations. Other scenarios of data recording and genotyping should be evaluated before considering the implementation of genomic selection in a pig-selection scheme based on sib testing of boars.

The proprotein convertase subtilisin/kexin type 1 (PCSK1) gene encodes the prohormone convertase 1/3 enzyme that processes prohormones into functional hormones that, in turn, regulate central and peripheral energy metabolism. Mutations in the human PCSK1 gene cause severe monogenic obesity or confer risk of obesity. We herein investigated the porcine PCSK1 gene with the aim of identifying polymorphisms associated with fat deposition and production traits in Italian heavy pigs. By re-sequencing about 5.1 kb of this gene in 21 pigs of different breeds, we discovered 14 polymorphisms that were organized in nine haplotypes, clearly distributed in two clades of putative European and Asian origin. Then we re-mapped this gene on porcine chromosome 2 and analysed its expression in several tissues including gastric oxyntic mucosa of weanling pigs in which PCSK1 processes the pre-pro-ghrelin into ghrelin, which in turn is involved in the control of feed intake and energy metabolism. Association analyses between PCSK1 single-nucleotide polymorphisms (SNPs) and production, carcass and several other traits were conducted on five groups of pigs from three different experimental designs, for a total of 1221 animals. Results indicated that the analysed SNPs were associated (P < 0.01 or P < 0.05) with several traits including backfat thickness and visible intermuscular fat in Italian Duroc (ID) and growth performances in Italian Large White (ILW) and in ILW × Italian Landrace pigs. However, the effects estimated in the ILW were opposite to the effects reported in the ID pigs. Suggestive association (P < 0.10) was observed with muscle cathepsin B activity, opening, if confirmed, potential applications to reduce the excessive softness defect of the green hams that is of particular concern for the processing industry. The results obtained supported the need to further investigate the PCSK1 gene to fully exploit the value of its variability and apply this information in pig breeding programmes.

The production of dry cured hams of high quality is the main aim of the Italian pork industry that is based on the breeding of heavy pigs (Russo and Nanni Costa, 1995). Genetic improvement programs are especially designed to fulfil the needs of this industry, that considers meat quality one of the main objectives. However, meat quality traits can be evaluated only post mortem, thus selection responses could be increased using associated DNA polymorphisms in marker assisted selection programs. Lysosomal proteinase activity has been indicated as a parameter useful to predict the quality of dry cured hams.........

Glycolytic Potential (GP) is an important parameter influencing pig meat quality. In order to identify genes and gene networks influencing glycolytic potential we utilized microarray analysis and studied the expression profile of skeletal muscle tissue from Italian Large White pigs with extreme high/low levels of GP. The knowledge of differentially expressed genes in groups of pigs with substantively different GP values could be a first step to understand the metabolic regulatory pathways influencing GP. The genes more expressed in the samples with low GP are mainly associated with energy metabolism while those more expressed in the samples with high GP are involved in intracellular transport. These results can give useful information to identify candidate genes for glycolytic potential level of pig meat.

The data collected in the first seven years of the 100-day Station Test for Italian Saddle Horse stallions have been used to estimate EBVs by single trait - repeatability AM-BLUP. There were 9449 scores for “character” and “gaits”, and 3564 for “jumping ability” in the training period; 344 scores for each trait were also available from the final evaluations assigned by two well-known professional riders; in the pedigree file of the 180 tested horses there were 2837 animals. Heritability estimates were .38±.02 and .23±.14 for “character”, .60±.02 and .58±.04 for “gaits”, and .48±.02 and .52±.04 for “jumping”, in the training period and in the final evaluation, respectively. The training period and the final evaluation were weighted 90% and 10% in each trait index, and the weights for “character”, “gaits” and “jumping” were 25%, 25% and 50% in the overall index. The genetic index was correlated .97 with the current official index, both linearly and in rank: therefore, the 82 licensed stallions give a selection intensity of .85, instead of the theoretical maximum of .87. Although the difference in the response to selection that the switching to BLUP could assure is low, the breeders could make comparisons between stallions approved in different editions.

The official results of trotters in Italian harness racings have been used to get AM-BLUP estimates of genetic parameters, EBVs and rTI of three groups of traits: speed (racing time, annual best time, best time in career between 2- and 5-year old), earnings (earnings/start, annual earnings, total earnings between 2- and 5- year old) and Elo system traits (underlying performance and final rating). The Elo system has been used for half a century in chess players rating, and it has been modified and fitted to several games and sports: it has already been used for genetic evaluation of sport horses in France. The highest heritability estimates in each group of traits have been found for best time (.430±.014), total earnings (.271±.013) and Elo final rating (.270±.008). The choice of “k”, the Elo ratings updating factor, did not show a key role in affecting the results. The underlying performance heritability and repeatability have been estimated .159±.004 and .420±.007 respectively. The Elo-based systems proved to be very promising in objectively evaluating trotters.

Sea cucumbers are deposit feeding members of marine benthic communities. The over-exploitation of sea cucumber natural stocks, especially in the Mediterranean basin, is having negative impacts on the marine ecosystem. This concerns had led the Italian government to take legal actions to preserve these important marine resources. The aim of this study was to evaluate the level of genetic diversity and population structures within two sympatric Holothuria sea cucumber species, H. polii and H. tubulosa, across ten Mediterranean areas along Italy. A 323 bp portion of the COI mitochondrial gene was sequenced in a total of 441 holothurians (251 H. polii, 177 H. tubulosa and 13 from other species). Genetic diversity analyses and analysis of molecular variance (AMOVA) suggest that H. polii and H. tubulosa species are distinct, but within and among populations are homogeneous, indicating active gene flows across the Mediterranean areas investigated. H. polii showed a lower genetic diversity than H. tubulosa, probably related to differences in life history traits. Phylogenetic analyses showed a clear differentiation between the two species, even if six specimens morphologically assigned to a species clustered within the other species, indicating a possible occurrence of hybridization events. These data will be useful in implementing conservation actions for these holothurian genetic resources., (© 2024. The Author(s).)

The gilthead seabream ( Sparus aurata ) is a species of relevance for the Mediterranean aquaculture industry. Despite the advancement of genetic tools for the species, breeding programs still do not often include genomics. In this study, we designed a genomic strategy to identify signatures of selection and genomic regions of high differentiation among populations of farmed fish stocks. A comparative DNA pooling sequencing approach was applied to identify signatures of selection in gilthead seabream from the same hatchery and from different nuclei that had not been subjected to genetic selection. Identified genomic regions were further investigated to detect SNPs with predicted high impact. The analyses underlined major genomic differences in the proportion of fixed alleles among the investigated nuclei. Some of these differences highlighted genomic regions, including genes involved in general metabolism and development already detected in QTL for growth, size, skeletal deformity, and adaptation to variation of oxygen levels in other teleosts. The obtained results pointed out the need to control the genetic effect of breeding programs in this species to avoid the reduction of genetic variability within populations and the increase in inbreeding level that, in turn, might lead to an increased frequency of alleles with deleterious effects.

The aim of this research has been to assess the effect of the dietary protein level on piglet growth and post-weaning diarrhea (PWD) incidence. Piglet fecal microbiota and feces composition were also assessed. The experiment was carried out on 144 weaned piglets (Duroc × Large White; 72 piglets per treatment) and lasted from weaning (at 25 days of age) until the end of the post-weaning phase (at 95 days). Two dietary protein levels were compared: high (HP; 17.5% crude protein on average, during the experiment) and low (LP; 15.5% on average). Lower ( p < 0.01) average daily gain and feed conversion ratio were observed in LP piglets in the first growth phase. However, at the end of the post-weaning period, the growth parameters were not significantly different in the two diets. Diarrhea scores were lower in piglets fed LP diets than in piglets fed HP diets (28.6% of the total vs. 71.4% in the HP piglets). Fibrobacteres , Proteobacteria, and Spirochaetes were more abundant in the feces of the piglets fed LP diets. Feces nitrogen content was lower in piglets fed LP diets. In conclusion, low protein levels in the diet can reduce the incidence of PWD while only marginally affecting growth parameters.

CXCL8 (also known as IL-8) is a member of the CXC subfamily of chemokines that binds two of the seven transmembrane G-protein-coupled receptors (GPCRs), CXCR1 and CXCR2, to mediate and regulate leucocyte accumulation and activation at sites of inflammation. They are known to play a critical role in both disease susceptibility and infection outcome. The aim of this study was to investigate the entire sequences of CXCL8 and CXCR2 genes in thirty-one Simmental sires to evaluate the effects of genomic variants on the indexes of the bulls for milk, fat and protein yields, and for somatic cell score (SCS). Five new single nucleotide polymorphisms (SNPs) were found in CXCR2 gene. The analysis of association indicated that one SNP in CXCL8 and two in CXCR2 influenced the considered traits. To evaluate the existence of functional haplotypic effects, combinations among the three genomic variants (SNP 1 in CXCL8 , SNP 6 and SNP 7 in CXCR2 ) were investigated. Four different haplotypic alleles were identified in the experimental population, one of which at a high frequency (61%). Bulls with Hap 4 (G-C-G at SNP 1, SNP 6, and SNP 7 respectively) had more favourable indexes for SCS ( P < 0.05). These results suggest that the SNPs in CXCL8 and CXCR2 may be potential genetic markers to improve udder health in the Simmental breed.

This study examined the environmental performance of mussel (Mytilus galloprovincialis) farming in the view of reduction of greenhouse gas emissions, through the Life Cycle Assessment (LCA) methodology. The LCA has been integrated with the evaluation of the carbon sequestration potential of the biocalcification process. Three case studies of mussel farming sited along the coastal area in the north Adriatic Sea, Italy, were analyzed. Two of them concerned mussels that do not require a depuration process (area Class A), and one inspected mussel production in the rearing area of Class B, which imposes a depuration phase after harvesting. This study examined all the relevant flows of materials and energy across the systems and explored the potential role of mussel biocalcification in stocking seawater carbon into the shells. Global Warming (GW) -related emissions amounted to 0.07-0.12 kg CO 2 eq for Class&#95;A case studies and to 0.53 kg CO 2 eq for Class&#95;B case study. Through biogenic calcification, 0.19-0.20 kg CO 2 kg -1 mussel is fixed in the shells, and 0.12 kg CO 2 kg -1 mussel is released. These flows resulted in a net sequestration of about 0.08 kg CO 2 kg -1 mussel. This study confirmed the good environmental performance of the mussel production in the farming systems analyzed. When considering greenhouse gasses emissions, the extent to which the seawater carbon fixed in the shell as calcium carbonate can be considered a carbon sink was discussed and substantiated by locally collected environmental data., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Cluster of differentiation 4 (CD4) is the accessory protein non-covalently bound to the T cell receptor that recognizes an invariant region of MHC class II on antigen presenting cells. Its cytoplasmic tail, physically associated with a protein tyrosine kinase, is important in the activation of helper/inducer T lymphocytes. In Bos taurus, CD4 gene is located on chromosome 5 from which two isoforms are transcribed, with a different number of amino acids due to splicing of exon 7 and variation in the reading frame. The aim of this study was to investigate the sequence of the entire CD4 gene in Simmental sires to evaluate the effects of genomic variants on the indexes of the bulls for milk, fat and protein yields, as well as somatic cell score. The associations among genomic variants and indexes were analysed using the Allele and GLM procedures of SAS 9.4. The analysis indicated that only four of the thirty-one identified SNPs influenced the considered traits. Identified variants insist on coding zones and intronic sequences, where we revealed the presence of sites for transcription factors. To evaluate the existence of haplotypic effects, combinations among the four genomic variants (SNP 3, SNP 8, SNP 11 and SNP 19) were investigated. Six different haplotypic alleles were identified, but only four of them were frequent enough to allow for an evaluation of any haplotypic effect (at least six copies in the examined sample): Hap1, Hap2, Hap3 and Hap6. The analysis of associations between the selected haplotypes in the CD4 gene with milk related indexes showed that bulls with Hap2 (T-A-C-C) had better indexes for milk and protein yields (P < 0.05), whereas the presence of the Hap1 haplotype (A-G-A-T) caused a significant decrease of the index for protein yield (P < 0.05). Frequencies of the two alleles Hap1 and Hap2 (9 and 36% respectively) make them of interest for their possible inclusion in breeding schemes and support the hypothesis of considering this gene as a candidate for the improvement of milk-related traits in the Simmental breed.

In organic poultry production it is important to rear animals with a dynamic attitude to take advantage of outdoor areas. Farmers are reluctant to use such strains due to their lower productivity and older slaughtering age. However, fast growing lines grown in organic system often suffer poor health and welfare conditions. The kinetic metabolism of chickens is correlated with different types of muscle fiber: type I (in red muscles or oxidative) for prolonged and moderate movement and type II (in white muscles or glycogenic) for fast movements. Red muscle metabolism produces energy mainly by β-oxidation of Highly Unsaturated n-3 Fatty Acids (HUFA). Accordingly, kinetic activity causes higher consume of HUFA in red muscles than in white muscles, so the ratio between n-3 HUFA and their precursor C18:3 n-3 (ALA) is likely to be smaller in red than in white muscles. However, these ratios are highly affected by the environment. To reduce the effect of environmental variables, we propose an "Activity index" as the difference between n-3 HUFA/ALA in white and red muscle within the same bird. This index, measured after slaughtering, should represent the activity performed by the chicken during its life. Given that birds in good health had the possibility of moving, the "Activity index" would measure the activity actually performed by the animals. Should birds of a given strain show a higher activity level, this would be an indication of the suitability of that strain to outdoor systems. This work verified the application of this "Activity index" on 90 birds from 6 genetic strains with known kinetic behavior reared in an experimental farm. The "Activity index" was also tested on chicken strains collected form commercial organic farms. The results confirmed that strains recognized for higher kinetic attitude actually walked more and their behavior was clearly detected by the "Activity index" estimated from their muscles., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

The gilthead seabream (Sparus aurata, Sparidae family) is commonly used for aquaculture. Despite its great economic value, several problems in its cultivation remain. One of the major concerns is the high frequency of morphological abnormalities occurring during the early developmental stages. Partial and/or total lack of operculum is the most frequent anomaly affecting the fish cranial region. The existence of genetic factors that can at least partially determine this defect has been hypothesized. In this work, two DNA pools of highly related fry, one composed of normal-looking (control) fish and the other lacking an operculum (case), were constructed and whole-genome resequencing data produced from the two were compared. The analysis revealed a 1 Mb region on chromosome 2 with higher heterozygosity in the lack of operculum DNA pool than in the control DNA pool, consistent with the enrichment, in the first DNA pool, of one or more haplotypes causing or predisposing to the defect together with other normal haplotypes. A window-based F ST analysis between the two DNA pools indicated that the same region had the highest divergence score. This region contained 2921 SNVs, 10 of which, with predicted high impacts (three splice donor and seven stop-gained variants), were detected in novel genes that are homologous to calcium-sensing receptor-like genes, probably involved in bone development. Other studies are needed to clarify the genetic mechanisms involved in predisposing fry to this deformity and then to identify associated markers that could be used in breeding programs to reduce the frequency of this defect in the broodstock., (© 2021 Stichting International Foundation for Animal Genetics.)

In the European rabbit (Oryctolagus cuniculus), a polytocous livestock species, the number of teats indirectly impacts the doe reproduction efficiency and, in turn, the sustainable production of rabbit meat. In this study, we carried out a genome-wide association study (GWAS) for the total number of teats in 247 Italian White does included in the Italian White rabbit breed selection program, by applying a selective genotyping approach. Does had either 8 (n = 121) or 10 teats (n = 126). All rabbits were genotyped with the Affymetrix Axiom OrcunSNP Array. Genomic data from the two extreme groups of rabbits were also analysed with the single-marker fixation index statistic and combined with the GWAS results. The GWAS identified 50 significant SNPs and the fixation index analysis identified a total of 20 SNPs that trespassed the 99.98th percentile threshold, 19 of which confirmed the GWAS results. The most significant SNP (P = 4.31 × 10 -11 ) was located on OCU1, close to the NUDT2 gene, a breast carcinoma cells proliferation promoter. Another significant SNP identified as candidate gene NR6A1, which is well known to play an important role in affecting the correlated number of vertebrae in pigs. Other significant markers were close to candidate genes involved in determining body length in mice. Markers associated with increased number of teats could be included in selection programmes to speed up the improvement for this trait in rabbit lines that need to increase maternal performances., (© 2021 Stichting International Foundation for Animal Genetics.)

New approaches are needed to improve the sustainability of feed production and utilization by ruminants. Promising approaches include increased use of buffaloes for more sustainable milk production, and arbuscular mycorrhizal fungi (AMF) to reduce crop production input needs. However, studies assessing the effect of crops grown in the presence of AMF on rumen microbial utilization are limited. Based on current knowledge, we hypothesized that maize grain grown on AMF-inoculated soil affected ruminal fermentation and microbiota, and that this effect differed between buffalo and cattle. A dietary cross-over study (four weeks per diet) was conducted using rumen-cannulated cattle ( n = 5) and buffalo ( n = 6) to assess the effect of maize grain (3.9% (w/v) of diet) grown on soil with or without AMF (15 kg/ha) on ruminal fermentation and microbiota. Production of maize on AMF-treated soil did not affect any of the assessed ruminal fermentation parameters, microbial concentrations, or prokaryotic community composition (using prokaryotic 16S rRNA gene sequence analysis). In contrast, host type had numerous effects. Protozoal counts, lactate, total VFA and isobutyrate, were significantly higher in buffaloes compared to cattle. Conversely, butyrate was significantly lower in buffaloes than in cattle. Host type explained 9.3% of the total variation in prokaryotic community composition, and relative abundance of nine amplicon sequence variants significantly differed between host types. These findings indicate that AMF treatment of maize crops has no detrimental impact on the value of the resulting maize grains as a ruminant feed, and provides additional insight into rumen-based differences between cattle and buffalo., (Copyright © 2020 Chiariotti, Edwards, Hermes, Catillo, Meo Zilio, Di Giovanni, Smidt and Buttazzoni.)