Feed Quality Traits Research Articles

Assessment of grain quality traits in mutant lines of winter barley

This study aimed to evaluate the variation among mutant lines derived from the winter barley variety Gigga, focusing on crucial feed quality traits such as protein, lysine, ash, fat, fiber content, and 1000-grain weight. Significant differences were identified in specific traits among the mutant lines, revealing promising candidates for further breeding programs. Mutant lines Gigga-25, Gigga-26, and Gigga-29 exhibited significantly higher protein content in their grains compared to the parent variety Gigga. In addition, Gigga-10 demonstrated elevated lysine content, while Gigga-4, Gigga-12, and Gigga-20 displayed increased 1000-grain weight. Of particular interest was Gigga-20, standing out for its exceptional combination of high protein content and favorable 1000-grain weight. This dual advantage positions Gigga-20 as a prime candidate for further investigation and potential integration into breeding programs, aiming to develop barley varieties with superior feed quality. Furthermore, a promising balance was observed in mutant lines Gigga-25 and Gigga-28, showcasing favorable proportions of protein and lysine content. These mutants present additional options for incorporation into breeding initiatives directed at enhancing the overall nutritional quality of feed grains.

A Genome-Wide Association Study of Biomass Yield and Feed Quality in Buffel Grass (Cenchrus ciliaris L.)

The development of modern genomic tools has helped accelerate genetic gains in the breeding program of food crops. More recently, genomic resources have been developed for tropical forages, providing key resources for developing new climate-resilient high-yielding forage varieties. In this study, we present a genome-wide association study for biomass yield and feed quality traits in buffel grass (Cenchrus ciliaris L. aka Pennisetum ciliare L.). Genome-wide markers, generated using the DArTSeq platform and mapped onto the Setaria italica reference genome, were used for the genome-wide association study. The results revealed several markers associated with biomass yield and feed quality traits. A total of 78 marker–trait associations were identified with R2 values ranging from 0.138 to 0.236. The marker–trait associations were distributed across different chromosomes. Of these associations, the most marker–trait associations (23) were observed on Chr9, followed by Chr5 with 12. The fewest number of marker–trait associations were observed on Chr4 with 2. In terms of traits, 17 markers were associated with biomass yield, 24 with crude protein, 26 with TDN, 14 with ADF, 10 with NDF and 6 with DMI. A total of 20 of the identified markers were associated with at least two traits. The identified marker–trait associations provide a useful genomic resource for the future improvement and breeding of buffel grass.

An Interdisciplinary Assessment of Biochemical and Antioxidant Attributes of Six Greek Vicia sativa L. Varieties.

Common vetch (Vicia sativa L.) is one of the most cultivated feed crops with extensive agricultural diversity and numerous cultivars. This study concerns the first-time investigation of the dry plant biomass and grains of six vetch cultivars to define the detailed fingerprint of their phenolic and fatty acid content, along with their respective antioxidant potencies. The results revealed a substantial variation in the feed quality traits among the tested Vicia sativa varieties, highlighting the crucial role and influence the genotype plays in the achievement of high-quality livestock nutrition. Among the six varieties tested, Istros and M-6900 displayed a particularly intriguing phytochemical profile characterized by elevated phenolic content, significant antioxidant potency and remarkably high fatty acid indices. These findings are indicative of the great potential of these varieties to function as suitable candidates for incorporation into farm animal diets either in the form of dry biomass (hay) or as a grain feed additive.

Productivity and Feed Quality Performance of Napier Grass (Cenchrus purpureus) Genotypes Growing under Different Soil Moisture Levels.

In the semi-arid and arid environments of Sub-Sharan Africa, forage availability throughout the year is insufficient and highly limited during the dry seasons due to limited precipitation. Thus, the identification of drought stress-tolerant forage cultivars is one of the main activities in forage development programs. In this study, Napier grass (Cenchrus purpureus), an important forage crop in Eastern and Central Africa that is broadly adapted to produce across tropical environments, was evaluated for its water use efficiency and production performance under field drought stress conditions. Eighty-four Napier grass genotypes were evaluated for their drought stress tolerance from 2018 to 2020 using agro-morphological and feed quality traits under two soil moisture stress regimes during the dry season, i.e., moderate (MWS) and severe (SWS) water stress conditions, and under rainfed conditions in the wet season (wet). Overall, the results indicated the existence of genotype variation for the traits studied. In general, the growth and productivity of the genotypes declined under SWS compared to MWS conditions. High biomass-yielding genotypes with enhanced WUE were consistently observed across harvests in each soil moisture stress regime. In addition, the top biomass-yielding genotypes produced the highest annual crude protein yield, indicating the possibility of developing high-feed-quality Napier grass genotypes for drought stress environments.

Grain and Straw Yield of Paddy Cultivars and Feed Quality Traits of Paddy Straw

Grain and Straw Yield of Paddy Cultivars and Feed Quality Traits of Paddy Straw

Insights Into the Genetic Architecture of Complex Traits in Napier Grass (Cenchrus purpureus) and QTL Regions Governing Forage Biomass Yield, Water Use Efficiency and Feed Quality Traits.

Napier grass is the most important perennial tropical grass native to Sub-Saharan Africa and widely grown in tropical and subtropical regions around the world, primarily as a forage crop for animal feed, but with potential as an energy crop and in a wide range of other areas. Genomic resources have recently been developed for Napier grass that need to be deployed for genetic improvement and molecular dissection of important agro-morphological and feed quality traits. From a diverse set of Napier grass genotypes assembled from two independent collections, a subset of 84 genotypes (although a small population size, the genotypes were selected to best represent the genetic diversity of the collections) were selected and evaluated for 2 years in dry (DS) and wet (WS) seasons under three soil moisture conditions: moderate water stress in DS (DS-MWS); severe water stress in DS (DS-SWS) and, under rainfed (RF) conditions in WS (WS-RF). Data for agro-morphological and feed quality traits, adjusted for the spatial heterogeneity in the experimental blocks, were collected over a 2-year period from 2018 to 2020. A total of 135,706 molecular markers were filtered, after removing markers with missing values >10% and a minor allele frequency (MAF) <5%, from the high-density genome-wide markers generated previously using the genotyping by sequencing (GBS) method of the DArTseq platform. A genome-wide association study (GWAS), using two different mixed linear model algorithms implemented in the GAPIT R package, identified more than 35 QTL regions and markers associated with agronomic, morphological, and water-use efficiency traits. QTL regions governing purple pigmentation and feed quality traits were also identified. The identified markers will be useful in the genetic improvement of Napier grass through the application of marker-assisted selection and for further characterization and map-based cloning of the QTLs.

Genetic variability of maize stover quality and the potential for genetic improvement of fodder value

Maize stover left after grain harvest constitutes an important source for livestock feed in most parts of East Africa, particularly during the dry season. In spite of its wide use and greater importance, breeding programs have given little attention to the improvement of stover quality and quantity. The objectives of this study were to assess the genetic variability of experimental and released (checks) maize varieties for stover feed quantity and quality, and their relationship with grain yield. Results from different trials conducted across locations using randomized complete block design (RCBD) in different sites in Ethiopia and Tanzania from 2004 to 2006 showed higher genotypic variation for grain and stover yields and stover feed quality traits. This confirmed the existence of exploitable genetic variation not only for grain yield but also for stover fodder quality and quantity. Positive relationship was also observed between grain and stover yields but the relation between stover fodder quality traits and grain yield, in most cases, was weak. Generally, the study pinpointed the possibility for simultaneous improvement of grain yield and stover traits to address the high demand existing for dual purpose food-feed type of maize genotypes in maize-livestock mixed farming system of East Africa.

Extractable soil nutrient effects on feed quality traits of crop residues in the semiarid rainfed mixed crop–livestock farming systems of Southern India

In the mixed crop–livestock systems, while general relation among feed quality, productivity and soil nutrient management have been reported, information on the effects of extractable soil nutrients on crop residue (CR) feed quality traits is scarce (e.g. in semiarid regions of Karnataka, India). In view of the increasingly important role of CR as feed components, in these farming systems, generating such information is a relevant research issue for sustainable development. Here, we report the occurrence and strength of relationships among extractable nutrients in soils and CR feed quality traits, and the effects of improved nutrients input on feed availability and feed quality of CR. Soil samples were collected from farmers’ fields in the semiarid zone of Karnataka and analyzed for available phosphorus (P), potassium (K), sulphur (S), zinc (Zn) and boron (B) using standard laboratory methods. Soil test results were clustered as low, medium or high based on the level of nutrient concentration. Four major farming systems involving nine crops and 419 farms were selected for on-farm trials. Under every sample farm, a plot with farmer’s practice (control) and improved fertilizer inputs (combined application of nutrients found deficient by soil testing) were laid. Performance of crops was recorded. Samples were collected for CR feed quality trait analysis using Near Infrared Reflectance Spectroscopy. The result showed that for cereal and oil crops, extractable soil S was significantly negatively associated with anti-feed quality traits such as neutral detergent fibre (NDF), acid detergent fibre (ADF), acid detergent lignin (ADL) (P < 0.01), but significantly positively related to metabolizable energy (ME) and in vitro digestibility (P < 0.01). Extractable B and K levels were associated positively and significantly with NDF, ADF and ADL for oil crops and cereals. Crop level associations, for most crops, showed similar trend. Improved fertilizer inputs affected CR yield much more than it did the quality. It increased ME productivity (ME ha−1) and thereof the potential milk yield ha−1 by as high as 40 % over the control. Therefore, balanced nutrient inputs on crop land positively impact productivity of the livestock compartment of mixed crop–livestock farming system, and this knowledge can build on the currently perceived need and benefits of balanced nutrient replenishment in crop–livestock system.

Correlation between NIRS generated and chemically measured feed quality data in barley (Hordeum vulgare), and potential use in QTL analysis identification

A study was performed to investigate the value of near infrared reflectance spectroscopy (NIRS) as an alternate method to analytical techniques for identifying QTL associated with feed quality traits. Milled samples from an F6-derived recombinant inbred Tallon/Scarlett population were incubated in the rumen of fistulated cattle, recovered, washed and dried to determine the in-situ dry matter digestibility (DMD). Both pre- and post-digestion samples were analysed using NIRS to quantify key quality components relating to acid detergent fibre, starch and protein. This phenotypic data was used to identify trait associated QTL and compare them to previously identified QTL. Though a number of genetic correlations were identified between the phenotypic data sets, the only correlation of most interest was between DMD and starch digested (r = -0.382). The significance of this genetic correlation was that the NIRS data set identified a putative QTL on chromosomes 7H (LOD = 3.3) associated with starch digested. A QTL for DMD occurred in the same region of chromosome 7H, with flanking markers fAG/CAT63 and bPb-0758. The significant correlation and identification of this putative QTL, highlights the potential of technologies like NIRS in QTL analysis.

QTL associated with barley (Hordeum vulgare) feed quality traits measured through in situ digestion

Barley (Hordeum vulgare) is a major feed source for the intensive livestock industry. Competitiveness against other cereal grains depends largely on the price per unit of expressed feed quality. The traits which contribute to feed quality in barley are largely quantitative in nature but little is known about their genetic control. A study to identify the quantitative trait loci (QTLs) associated with feed quality was performed using a F6-derived recombinant inbred barley population. Samples from each line were incubated in the rumen of fistulated cattle, recovered, washed and dried for determination of in situ dry matter digestibility. Additionally, both pre- and post-digestion samples were analysed to quantify the content of key quality components relating to acid detergent fibre, total starch and protein. The data was used to identify trait-associated QTLs. Genetic analysis identified significant QTLs on chromosomes 2H, 5H and 7H. Genetic markers linked to these QTL should provide an effective tool for the selection and improvement of feed barley in the future.

Variation in feed quality traits for beef cattle in Steptoe × Morex barley population

Barley is a major feed source for livestock in the western regions of North America. Feed quality of beef cattle has been neglected as a selection criterion because of lack of understanding of the feed characteristics that could be responsive to selection and would improve feedlot performance. A Steptoe × Morex population was planted in irrigated and rain-fed environments, and collected data were used to evaluate the genetic variation in dry matter and starch digestibilities, acid detergent fiber, protein and starch contents, and to map quantitative trait loci controlling the variation in these traits. Transgressive genotypes indicate the wide genetic variation of these traits. High heritability estimates for these traits suggest that early selection for these traits during breeding would be achievable. A total of 32 main effect QTL and five epistatic QTL were identified which conditioned feed traits on different barley chromosomes. QTL for acid detergent fiber and starch contents overlapped on chromosome 6H at the Nar7 locus. Tight negative correlation between the two traits suggest the usability of Nar7 as anchor marker in marker-assisted selection programs to develop barley with low acid detergent fiber and high starch content.

Site-specific excisional recombination strategies for elimination of undesirable transgenes from crop plants

A major limitation of crop biotechnology and breeding is the lack of efficient molecular technologies for precise engineering of target genomic loci. While transformation procedures have become routine for a growing number of plant species, the random introduction of complex transgenenic DNA into the plant genome by current methods generates unpredictable effects on both transgene and homologous native gene expression. The risk of transgene transfer into related plant species and consumers is another concern associated with the conventional transformation technologies. Various approaches to avoid or eliminate undesirable transgenes, most notably selectable marker genes used in plant transformation, have recently been developed. These approaches include cotransformation with two independent T-DNAs or plasmid DNAs followed by their subsequent segregation, transposon-mediated DNA elimination, and most recently, attempts to replace bacterial T-DNA borders and selectable marker genes with functional equivalents of plant origin. The use of site-specific recombination to remove undesired DNA from the plant genome and concomitantly, via excision-mediated DNA rearrangement, switch-activate by choice transgenes of agronomical, food or feed quality traits provides a versatile “transgene maintenance and control” strategy that can significantly contribute to the transfer of transgenic laboratory developments into farming practice. This review focuses on recent reports demonstrating the elimination of undesirable transgenes (essentially selectable marker and recombinase genes) from the plant genome and concomitant activation of a silent transgene (e.g., a reporter gene) mediated by different site-specific recombinases driven by constitutive or chemically, environmentally or developmentally regulated promoters. These reports indicate major progress in excision strategies which extends application of the technology from annual, sexually propagated plants towards perennial, woody and vegetatively propagated plants. Current trends and future prospects for optimization of excision-activation machinery and its practical implementation for the generation of transgenic plants and plant products free of undesired genes are discussed.

Genetic Analysis of Kafirins and Their Phenotypic Correlations with Feed Quality Traits, In Vitro Digestibility, and Seed Weight in Grain Sorghum

ABSTRACTTwenty‐three entries of grain sorghum (Sorghum bicolor (L.) Moench), including eight inbred lines (five males and three females) and 15 hybrids, were evaluated to determine the proportion of γ, αII, and β‐αI‐kafirins and their association with contents of crude protein, fat, and starch; protein digestibility; in vitro dry matter disappearance; and seed weight. The male lines included three normal‐seeded lines (TX2737, TX435, and P954063) and two large‐seeded lines (Eastin1 and PL‐1). Female lines consisted of three common U.S. seed parent lines (Wheatland, Redlan, and SA3042). The lines and their hybrids were grown under dryland conditions at two locations in Kansas using a randomized complete block design. The effects of genotype, location, and males were significant for all kafirins. Wide variations in composition and general combining ability (GCA) for kafirin content were noted among parent lines and hybrids, with TX2737, Eastin1, and PL1 having the largest GCA values for γ (1.37), αII (1.99), and β‐αI (2.57), respectively. Correlations among kafirins ranged from ‐0.89 to 0, whereas those of kafirins with feed quality traits, digestibility, and seed weight ranged from ‐0.45 to 0.48.