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The objective of this study was to quantify the economic utility in Romosinuano production systems by developing a bioeconomic model assumed cow-calf, cow-calf plus stocker (CCPS), and complete cycle operations. Each system produced males for sale and females for replacement. Input parameters were established from breed data collected by AGROSAVIA. Revenues were estimated using the official cattle price, and production costs were quantified per activity. In the results, for cow-calf operations, the maximum economic utility was 244.12 USD. CCPS, yielded 231.86 USD, and Complete cycle, 268.94 USD. The genetic progress per generation for W240, W480, W24 and CI was + 3.8 kg, + 5 kg, + 5.9 kg, and -1 d, respectively. The price of livestock was the sensitized variable with the greatest impact on maximum economic utility (± 118.64 USD to ± 155.44 USD), followed by mineral supplementation (16.31 USD to ± 37.34 USD). The sensitized variables with the lowest impact were food (± 1.62 USD to ± 1.8 USD) and health plan supplies (± 6.03 USD to ± 9.13 USD). It is concluded that economic utility defined as a composite trait influenced by the characteristics that shape it favors genetic progress and the identification of animals with optimal performance in different bovine production systems.

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The increasing global demand for food and the strong effect of climate change have forced animal science to advance regarding new methods of selection in search of more efficient animals in production systems. Feed consumption represents more than 70% of the costs of sheep farms, and more efficient animals can increase the farmers' profitability. One of the main measures of feed efficiency is estimated residual feed intake (RFI), created in 1963 by Robert Koch for estimation in cattle and later adapted for sheep. Animals with negative RFI values (RFI-) are more efficient than animals with positive values (RFI+), with influence on the variables of performance, carcass quality and production of enteric gases. The RFI is the most common and accepted metric of the feed efficiency trait for genetic selection, since it is independent of growth traits, unlike the feed conversion ratio. The purpose of this review article was to present updated literature information on the relationship of RFI estimates with performance measures, molecular markers, greenhouse gas production and feed efficiency, the technical aspects and physiological basis of metabolic in sheep.

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This study evaluated the effects of antral follicle count (AFC) in female cattle on offspring characteristics. Recently calved multiparous Bos indicus cows (Nelore; n = 222) were evaluated using ultrasonography on random days of their estrous cycle to determine the AFC and were classified into "low" (≤15 follicles), "intermediate" (≥16 and ≤ 29 follicles), and "high" (≥30 follicles) AFC groups. Weight and scrotal circumference (SC) of male offspring from these cows (n = 127) were determined from 20 to 27 months, and the data were added to a genetic evaluation program (economic total genetic merit, MGTe and TOP value) that uses the kinship matrix to evaluate the genetic relationship between animals. The AFC of female offspring from these cows (n = 95) was evaluated to analyze the relationship between the AFC of mothers and daughters. The effects of maternal AFC on the genetic merit of male and female offspring were analyzed using GLIMMIX and GLM, respectively. Correlations were assessed using the Pearson's coefficient. Male offspring of cows with high AFC had superior MGTe (P = 0.005) and TOP values (P = 0.01) than those from cows with low AFC. Additionally, the AFC of mothers was positively correlated with MGTe (R = 0.33; P < 0.0001) and negatively correlated with TOP values (R = -0.32; P < 0.0001). The SC (P = 0.01), but not body weight of the offspring (P = 0.46) was affected by maternal AFC. The daughters' AFC were correlated (R = 0.29; P = 0.004) with mothers' AFC and were influenced by maternal (P = 0.05) but not paternal (P = 0.77) effect. In conclusion, cows with high AFC produced males with greater MGTe, superior TOP values and higher SC. Maternal AFC did not influence the weight of male offspring but was correlated with the AFC of daughters.

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The effect of different percentages of Duroc genes in crossbreeding (5, 50 and 100%), the gender (immunocastrated males - ICM and females) and their interaction was evaluated on growth, carcass and meat quality traits for pigs. Crossbreds (50% Duroc) had greater average daily feed intake, hot carcass weight and backfat thickness but lower meat yield when compared to 5% Duroc crossbreds and purebred (100% Duroc) animals (P < 0.05). Purebred (100% Duroc) animals had the lowest backfat thickness and subcutaneous fat thickness, and the greatest muscle depth and meat yield (P < 0.05). ICM animals had better feed conversion, greater average daily gain, hot carcass weight and amount of meat, and lower hot carcass yield, cold carcass weight, Longissimus thoracis depth, rib with belly and ham weights compared to females (P < 0.05). Marbling scores were greater in purebred (100%) animals (P < 0.05). The meat from 50% Duroc crossbreds and 100% Duroc purebred pigs was more reddish pink in color than 5% Duroc crossbreds (P < 0.05). Also, marbling scores were greater for females compared to ICM (P < 0.05). Purebred (100% Duroc) animals required more medications during production (P < 0.05).

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This paper aims to review, systematically synthesize, and analyze fragmented information about the importance of coat color in local goats and its relationship with productivity and other important traits. Topics on current research on color expression are addressed, the relationship that has as a mechanism of environmental adaptation, its relationship with the production of meat, milk, and derivates, and the economic value of this characteristic. The use of this attribute as a tool to establish selection criteria in breeding programs based on results reported in the scientific literature is significant, particularly for low-income production systems, where the implementation of classic genetic improvement schemes is limited due to the lack of productive information, which is distinctive of extensive marginal or low scaled production systems around the world.

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For popcorn, obtaining and identifying haploids are still challenging steps. We aimed to induce and screen haploids in popcorn using the Navajo phenotype, seedling vigor, and ploidy level. We used the Krasnodar Haploid Inducer (KHI) in crosses with 20 popcorn source germplasms and five maize controls. The field trial design was completely randomized, with three replications. We assessed the efficacy of induction and identification of haploids based on the haploidy induction rate (HIR) and false positive and negative rates (FPR and FNR). Additionally, we also measured the penetrance of the Navajo marker gene (R1-nj). All putative haploids classified by the R1-nj were germinated together with a diploid sample and evaluated for false positives and negatives based on vigor. Seedlings from 14 females were submitted to flow cytometry to determine the ploidy level. The HIR and penetrance were analyzed by fitting a generalized linear model with a logit link function. The HIR of the KHI, adjusted by cytometry, ranged from 0.0 to 1.2%, with a mean of 0.34%. The average FPR from screening based on the Navajo phenotype was 26.2% and 76.4% for vigor and ploidy, respectively. The FNR was zero. The penetrance of R1-nj ranged from 30.8 to 98.6%. The average number of seeds per ear in temperate germplasm (76) was lower than that obtained in tropical germplasm (98). There is an induction of haploids in germplasm of tropical and temperate origin. We recommend the selection of haploids associated with the Navajo phenotype with a direct method of confirming the ploidy level, such as flow cytometry. We also show that haploid screening based on Navajo phenotype and seedling vigor reduces misclassification. The origin and genetic background of the source germplasm influence the R1-nj penetrance. Because the known inducers are maize, developing doubled haploid technology for popcorn hybrid breeding requires overcoming unilateral cross-incompatibility.

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Many reproductive physiological processes, such as folliculogenesis, ovulation, implantation, and fertilization, require the synthesis, remodeling, and degradation of the extracellular matrix (ECM). The ADAMTS (A Disintegrin and Metalloproteinase with Thrombospondin Motifs) family genes code for key metalloproteinases in the remodeling process of different ECM. Several genes of this family encode for proteins with important functions in reproductive processes; in particular, ADAMTS1, 4, 5 and 9 are genes that are differentially expressed in cell types and the physiological stages of reproductive tissues. ADAMTS enzymes degrade proteoglycans in the ECM of the follicles so that the oocytes can be released and regulate follicle development during folliculogenesis, favoring the action of essential growth factors, such as FGF-2, FGF-7 and GDF-9. The transcriptional regulation of ADAMTS1 and 9 in preovulatory follicles occurs because of the gonadotropin surge in preovulatory follicles, via the progesterone/progesterone receptor complex. In addition, in the case of ADAMTS1, pathways involving protein kinase A (PKA), extracellular signal regulated protein kinase (ERK1/2) and the epidermal growth factor receptor (EGFR) might contribute to ECM regulation. Different Omic studies indicate the importance of genes of the ADAMTS family from a reproductive aspect. ADAMTS genes could serve as biomarkers for genetic improvement and contribute to enhance fertility and animal reproduction; however, more research related to these genes, the synthesis of proteins encoded by these genes, and regulation in farm animals is needed.

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Vanilla planifolia is an orchid of cultural and economic value. However, its cultivation in many tropical countries is threatened by water stress. In contrast, V. pompona is a species that is tolerant of prolonged periods of drought. Due to the need for plants' resistant to water stress, the use of hybrids of these two species is considered. Therefore, the objective of this study was to evaluate the morphological and physio-chemical responses of in vitro vanilla seedlings of the parental genotype V. planifolia, and the hybrids V. planifolia × V. pompona and V. pompona × V. planifolia, which were then exposed over five weeks to polyethylene glycol-induced water stress (-0.49 mPa). Stem and root length, relative growth rate, number of leaves and roots, stomatal conductance, specific leaf area, and leaf water content were determined. Metabolites potentially associated with the response to water stress were identified in leaves, through untargeted and targeted metabolomics. Both hybrids exhibited a smaller decrease in the morphophysiological responses compared to V. planifolia and exhibited an enrichment of metabolites such as carbohydrates, amino acids, purines, phenols, and organic acids. Hybrids of these two species are considered as a potential alternative to the traditional cultivation of vanilla to face drought in a global warming scenario.

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Agricultural crops are exposed to various abiotic stresses, such as salinity, water deficits, temperature extremes, floods, radiation, and metal toxicity. To overcome these challenges, breeding programs seek to improve methods and techniques. Gene editing by Clustered Regularly Interspaced Short Palindromic Repeats-CRISPR/Cas-is a versatile tool for editing in all layers of the central dogma with focus on the development of cultivars of plants resistant or tolerant to multiple biotic or abiotic stresses. This systematic review (SR) brings new contributions to the study of the use of CRISPR/Cas in gene editing for tolerance to abiotic stress in plants. Articles deposited in different electronic databases, using a search string and predefined inclusion and exclusion criteria, were evaluated. This SR demonstrates that the CRISPR/Cas system has been applied to several plant species to promote tolerance to the main abiotic stresses. Among the most studied crops are rice and Arabidopsis thaliana, an important staple food for the population, and a model plant in genetics/biotechnology, respectively, and more recently tomato, whose number of studies has increased since 2021. Most studies were conducted in Asia, specifically in China. The Cas9 enzyme is used in most articles, and only Cas12a is used as an additional gene editing tool in plants. Ribonucleoproteins (RNPs) have emerged as a DNA-free strategy for genome editing without exogenous DNA. This SR also identifies several genes edited by CRISPR/Cas, and it also shows that plant responses to stress factors are mediated by many complex-signaling pathways. In addition, the quality of the articles included in this SR was validated by a risk of bias analysis. The information gathered in this SR helps to understand the current state of CRISPR/Cas in the editing of genes and noncoding sequences, which plays a key role in the regulation of various biological processes and the tolerance to multiple abiotic stresses, with potential for use in plant genetic improvement programs.

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The inheritance of the seedless fruit characteristic of Annona squamosa has not yet been explained. Molecular techniques may aid breeding programs, mainly in the assisted selection of the target gene. The INO gene may be related to seed development in these fruits. The objective of the present paper was to investigate the inheritance of seedlessness in the 'Brazilian seedless' sugar apple and INO gene conservation in Annona squamosa and Annona cherimola x Annona squamosa genotypes by assessing their homology with the INO database genes. The F1 generation was obtained by crossing the mutant 'Brazilian seedless' (male genitor) (P1) with the wild-type A. squamosa with seeds (M1 and M2, female genitors). The INO gene was studied in mutant and wild-type A. squamosa (P1, M1, M2 and M3) and in the Gefner atemoya (A. cherimola x A. squamosa) (M4) cultivar. The DNA was extracted from young leaves, and four sets of specific primers flanking the INO gene were amplified. The seedless characteristic was identified as stenospermatic in the fruits of parental P1, suggesting monogenic inheritance with complete dominance. High sequence similarity of the INO gene amplifications in the sugar apple accessions (M1, M2, M3) and the atemoya cultivar Gefner (M4) reinforces the hypothesis of their conservation.

A herança da característica de fruto sem sementes de Annona squamosa ainda não foi esclarecida. Técnicas moleculares podem auxiliar em programas de melhoramento, principalmente na seleção assistida do gene de interesse. O gene INO pode estar relacionado ao desenvolvimento da semente dessas frutas. O objetivo foi investigar a herança da ausência de sementes em Annona squamosa e a conservação do gene INO nos genótipos Annona squamosa e Annona cherimola x Annona squamosa avaliando sua homologia com banco de dados de genes INO. A geração F1 foi obtida pelo cruzamento do mutante 'Brazilian seedless' (genitor masculino) (P1) com o tipo selvagem com sementes (A. squamosa) (M1 e M2, genitores femininos). O gene INO foi estudado em A. squamosa, mutante e selvagem (P1, M1, M2 e M3) e na cultivar Gefner atemoya (A. cherimola x A. squamosa) (M4). O DNA foi extraído de folhas jovens, e quatro conjuntos de primers específicos flanqueando o gene INO foram amplificados. A característica sem sementes foi identificada como estenospermática nos frutos do parental P1, sugerindo herança monogênica com dominância completa. A alta similaridade de sequência das amplificações do gene INO nos acessos de pinha (M1, M2, M3) e na cultivar de atemóia Gefner (M4) reforça a hipótese de sua conservação.

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Abstract The inheritance of the seedless fruit characteristic of Annona squamosa has not yet been explained. Molecular techniques may aid breeding programs, mainly in the assisted selection of the target gene. The INO gene may be related to seed development in these fruits. The objective of the present paper was to investigate the inheritance of seedlessness in the 'Brazilian seedless' sugar apple and INO gene conservation in Annona squamosa and Annona cherimola x Annona squamosa genotypes by assessing their homology with the INO database genes. The F1 generation was obtained by crossing the mutant 'Brazilian seedless' (male genitor) (P1) with the wild-type A. squamosa with seeds (M1 and M2, female genitors). The INO gene was studied in mutant and wild-type A. squamosa (P1, M1, M2 and M3) and in the Gefner atemoya (A. cherimola x A. squamosa) (M4) cultivar. The DNA was extracted from young leaves, and four sets of specific primers flanking the INO gene were amplified. The seedless characteristic was identified as stenospermatic in the fruits of parental P1, suggesting monogenic inheritance with complete dominance. High sequence similarity of the INO gene amplifications in the sugar apple accessions (M1, M2, M3) and the atemoya cultivar Gefner (M4) reinforces the hypothesis of their conservation.

Resumo A herança da característica de fruto sem sementes de Annona squamosa ainda não foi esclarecida. Técnicas moleculares podem auxiliar em programas de melhoramento, principalmente na seleção assistida do gene de interesse. O gene INO pode estar relacionado ao desenvolvimento da semente dessas frutas. O objetivo foi investigar a herança da ausência de sementes em Annona squamosa e a conservação do gene INO nos genótipos Annona squamosa e Annona cherimola x Annona squamosa avaliando sua homologia com banco de dados de genes INO. A geração F1 foi obtida pelo cruzamento do mutante 'Brazilian seedless' (genitor masculino) (P1) com o tipo selvagem com sementes (A. squamosa) (M1 e M2, genitores femininos). O gene INO foi estudado em A. squamosa, mutante e selvagem (P1, M1, M2 e M3) e na cultivar Gefner atemoya (A. cherimola x A. squamosa) (M4). O DNA foi extraído de folhas jovens, e quatro conjuntos de primers específicos flanqueando o gene INO foram amplificados. A característica sem sementes foi identificada como estenospermática nos frutos do parental P1, sugerindo herança monogênica com dominância completa. A alta similaridade de sequência das amplificações do gene INO nos acessos de pinha (M1, M2, M3) e na cultivar de atemóia Gefner (M4) reforça a hipótese de sua conservação.

RESUMO

Abstract The inheritance of the seedless fruit characteristic of Annona squamosa has not yet been explained. Molecular techniques may aid breeding programs, mainly in the assisted selection of the target gene. The INO gene may be related to seed development in these fruits. The objective of the present paper was to investigate the inheritance of seedlessness in the 'Brazilian seedless' sugar apple and INO gene conservation in Annona squamosa and Annona cherimola x Annona squamosa genotypes by assessing their homology with the INO database genes. The F1 generation was obtained by crossing the mutant 'Brazilian seedless' (male genitor) (P1) with the wild-type A. squamosa with seeds (M1 and M2, female genitors). The INO gene was studied in mutant and wild-type A. squamosa (P1, M1, M2 and M3) and in the Gefner atemoya (A. cherimola x A. squamosa) (M4) cultivar. The DNA was extracted from young leaves, and four sets of specific primers flanking the INO gene were amplified. The seedless characteristic was identified as stenospermatic in the fruits of parental P1, suggesting monogenic inheritance with complete dominance. High sequence similarity of the INO gene amplifications in the sugar apple accessions (M1, M2, M3) and the atemoya cultivar Gefner (M4) reinforces the hypothesis of their conservation.

Resumo A herança da característica de fruto sem sementes de Annona squamosa ainda não foi esclarecida. Técnicas moleculares podem auxiliar em programas de melhoramento, principalmente na seleção assistida do gene de interesse. O gene INO pode estar relacionado ao desenvolvimento da semente dessas frutas. O objetivo foi investigar a herança da ausência de sementes em Annona squamosa e a conservação do gene INO nos genótipos Annona squamosa e Annona cherimola x Annona squamosa avaliando sua homologia com banco de dados de genes INO. A geração F1 foi obtida pelo cruzamento do mutante 'Brazilian seedless' (genitor masculino) (P1) com o tipo selvagem com sementes (A. squamosa) (M1 e M2, genitores femininos). O gene INO foi estudado em A. squamosa, mutante e selvagem (P1, M1, M2 e M3) e na cultivar Gefner atemoya (A. cherimola x A. squamosa) (M4). O DNA foi extraído de folhas jovens, e quatro conjuntos de primers específicos flanqueando o gene INO foram amplificados. A característica sem sementes foi identificada como estenospermática nos frutos do parental P1, sugerindo herança monogênica com dominância completa. A alta similaridade de sequência das amplificações do gene INO nos acessos de pinha (M1, M2, M3) e na cultivar de atemóia Gefner (M4) reforça a hipótese de sua conservação.

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The inheritance of the seedless fruit characteristic of Annona squamosa has not yet been explained. Molecular techniques may aid breeding programs, mainly in the assisted selection of the target gene. The INO gene may be related to seed development in these fruits. The objective of the present paper was to investigate the inheritance of seedlessness in the 'Brazilian seedless' sugar apple and INO gene conservation in Annona squamosa and Annona cherimola x Annona squamosa genotypes by assessing their homology with the INO database genes. The F1 generation was obtained by crossing the mutant 'Brazilian seedless' (male genitor) (P1) with the wild-type A. squamosa with seeds (M1 and M2, female genitors). The INO gene was studied in mutant and wild-type A. squamosa (P1, M1, M2 and M3) and in the Gefner atemoya (A. cherimola x A. squamosa) (M4) cultivar. The DNA was extracted from young leaves, and four sets of specific primers flanking the INO gene were amplified. The seedless characteristic was identified as stenospermatic in the fruits of parental P1, suggesting monogenic inheritance with complete dominance. High sequence similarity of the INO gene amplifications in the sugar apple accessions (M1, M2, M3) and the atemoya cultivar Gefner (M4) reinforces the hypothesis of their conservation.(AU)

A herança da característica de fruto sem sementes de Annona squamosa ainda não foi esclarecida. Técnicas moleculares podem auxiliar em programas de melhoramento, principalmente na seleção assistida do gene de interesse. O gene INO pode estar relacionado ao desenvolvimento da semente dessas frutas. O objetivo foi investigar a herança da ausência de sementes em Annona squamosa e a conservação do gene INO nos genótipos Annona squamosa e Annona cherimola x Annona squamosa avaliando sua homologia com banco de dados de genes INO. A geração F1 foi obtida pelo cruzamento do mutante 'Brazilian seedless' (genitor masculino) (P1) com o tipo selvagem com sementes (A. squamosa) (M1 e M2, genitores femininos). O gene INO foi estudado em A. squamosa, mutante e selvagem (P1, M1, M2 e M3) e na cultivar Gefner atemoya (A. cherimola x A. squamosa) (M4). O DNA foi extraído de folhas jovens, e quatro conjuntos de primers específicos flanqueando o gene INO foram amplificados. A característica sem sementes foi identificada como estenospermática nos frutos do parental P1, sugerindo herança monogênica com dominância completa. A alta similaridade de sequência das amplificações do gene INO nos acessos de pinha (M1, M2, M3) e na cultivar de atemóia Gefner (M4) reforça a hipótese de sua conservação.(AU)

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The objective of this review is to bring information about innovations and technologies that, through genetic improvement, are being used to improve the sustainability and productivity of agricultural crops, improve human nutrition, as well as conservation and decontamination of soils. Bioremediation consists of using microorganisms that have the ability to modify or decompose certain pollutants, with the possibility of increasing their activity through genetic engineering, building new strains for the transformation of pollutants into inert substances. Genetic improvement is seeking to develop cultivars that are more tolerant to periods of water deficit. Plant biofortification consists of varieties of improved plants that have a higher content of vitamins and minerals, which are obtained through genetic improvement. Thus, biotechnology is once again essential for world agricultural production and can bring a series of other benefits to society.(AU)

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In vitro germplasm conservation allows to extend the interval between subcultures without compromising the viability and genetic integrity of the plant, ensuring a backup of genotypes with high phytosanitary quality. Thus, this study aimed to verify the effect of four concentrations of Paclobutrazol® in inducing minimum growth in five Manihot esculenta accessions from the in vitro Active Germplasm Bank of Embrapa Cassava and Fruits. An experiment was installed using the Murashige and Skoog medium without addition and added with four concentrations of Paclobutrazol® (0.10, 0.20, 0.30, and 0.40 mg L-1), in five in vitro accessions of M. esculenta: BRS Jari (BGM 2041), Cigana (BGM 0264), BRS Poti Branca (BGM 2017), TME 14, and BRS Novo Horizonte. The statistical design was completely randomized in a 5 x 5 factorial scheme, with 15 repetitions. After 120 days of cultivation, the following variables were evaluated: plant height (cm), number of green leaves, number of senescent leaves, number of mini-cuttings, number of shoots, and fresh and dry mass of shoots and roots (mg). Paclobutrazol® caused a reduction in plant height and gain in root mass for all accessions, in addition to preserving the number of green leaves and decreasing leaf senescence for most genotypes. There was a strong dependence of the genotype in relation to the concentration of Paclobutrazol®. The concentration of 0.20 mg L-1 showed potential in the in vitro conservation of M. esculenta genotypes.(AU)

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ABSTRACT: Physalisperuviana L. (physalis) has significant economic potential by virtue of the unique flavor of its fruit. However, the productivity of Brazilian plantations is low because of the limited number of varieties or cultivars available. The main obstacle in the selection of superior genotypes is the lack of information about genetic variability within- and between- populations and limited genetic basis that has likely resulted from evolutionary, domestication and selection processes of the natural or artificial populations. Physalis currently cultivated in Brazil is tetraploid, and such polyploidy may have led to the reproductive isolation of the species, preventing the occurrence of intraspecific hybridization. Moreover, cultivated populations derive from a common gene pool and have undergone a long process of domestication and selection carried out empirically by farmers. In Colombia and other Andean countries there are wild populations that exhibit genetic diversity which; although, fundamental for the conservation of the species, have low potential for the development of genotypes with superior agronomic traits. In order to create and expand the genetic variability of physalis, breeders have employed various strategies including induction of mutation, chromosome duplication, and interspecific and intraspecific hybridization. Furthermore, the production of double haploid lines from in vitro anther cultures has shown good results in the selection of hybrids. The mutant genotypes and/or hybrids obtained using these methods in association with those of wide genomic selection can generate cultivars with superior agronomic traits.

RESUMO: Physalis peruviana L. (fisális) apresenta grande potencial econômico devido ao sabor diferenciado de seus frutos. A produtividade dos pomares brasileiros é baixa em função do número limitado de variedades ou cultivares disponíveis. O principal entrave na seleção de genótipos superiores é a falta de informação sobre a variabilidade genética dentro e entre as populações de fisális e, possivelmente, a base genética limitada das mesmas, que pode ser explicada pelos processos evolutivos, de domesticação e de seleção das populações naturais ou artificiais. A fisális cultivada atualmente no Brasil é tetraploide e tal poliploidia pode ter levado ao isolamento reprodutivo da espécie, o qual impede a ocorrência de hibridação intraespecífica. As populações cultivadas provêm de um pool genético comum e, além disso, sofreram um longo processo de domesticação e seleção realizadas empiricamente pelos agricultores. Porém, na Colômbia e em outros países andinos existem populações silvestres que exibem diversidade genética que, embora sejam fundamentais para a conservação da espécie, apresentam baixo potencial para o desenvolvimento de genótipos com características agronômicas superiores. A fim de criar e ampliar a variabilidade genética de fisális, os melhoristas tem empregado várias estratégias incluindo a indução de mutação, a duplicação cromossômica e a hibridação inter e intraespecífica. Além disso, a produção de linhagens duplo-haploides a partir da cultura de anterasin vitro vem demonstrando bons resultados para a seleção de híbridos. Os genótipos mutantes e/ou híbridos obtidos através dos métodos citados em associação com os de seleção genômica ampla podem gerar cultivares com características agronômicas superiores.

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Among the multi-trait models selected to study several traits and environments jointly, the Bayesian framework has been a preferred tool when constructing a more complex and biologically realistic model. In most cases, non-informative prior distributions are adopted in studies using the Bayesian approach. However, the Bayesian approach presents more accurate estimates when informative prior distributions are used. The present study was developed to evaluate the efficiency and applicability of multi-trait multi-environment (MTME) models within a Bayesian framework utilizing a strategy for eliciting informative prior distribution using previous data on rice. The study involved data pertaining to rice (Oryza sativa L.) genotypes in three environments and five crop seasons (2010/2011 until 2014/2015) for the following traits: grain yield (GY), flowering in days (FLOR) and plant height (PH). Variance components, genetic and non-genetic parameters were estimated using the Bayesian method. In general, the informative prior distribution in Bayesian MTME models provided higher estimates of individual narrow-sense heritability and variance components, as well as minor lengths for the highest probability density interval (HPD), compared to their respective non-informative prior distribution analyses. More informative prior distributions make it possible to detect genetic correlations between traits, which cannot be achieved with non-informative prior distributions. Therefore, this mechanism presented to update knowledge for an elicitation of an informative prior distribution can be efficiently applied in rice breeding programs.

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RESUMO

Background: Litter size at birth (LSB) is one of the most important economic traits in sheep and could be used in genetic improvement schemes for meat production. LSB is inherently a categorical trait and should be analysed with threshold models. Objective: Bayesian threshold models were used to analyze sheep LSB to estimate genetic parameters. Methods: Data was based on 7,901 LSB records from 14,968 dams and 682 sires collected from 1986 to 2012 at Makouie Sheep Breeding Station in Iran. Means of posterior distributions (MPDs) of LSB's genetic parameters were estimated, and the best-fitted models were selected using the deviance information criterion. Results: In the repeated measurement analysis, the estimated direct and maternal heritabilities, and permanent environmental effect (±SE), according to the best-fitted model (model 5), were 0.01 (0.010), 0.02 (0.014), and 0.01 (0.011), respectively. In the univariate analysis, the best estimates of direct and maternal heritabilities were 0.12 (0.064) and 0.08 (0.045), respectively. An increasing trend for direct and maternal heritabilities was observed in parity 2 (0.15 (0.082) and 0.25 (0.083), respectively). In the bivariate analysis, the best estimates of direct and maternal heritabilities for LSB were 0.03 (0.027) and 0.22 (0.041), respectively. The direct and maternal genetic correlations among parities were 0.25 (0.054) and 0.12 (0.021), respectively. Conclusions: The results showed a considerable influence of environmental factors on LSB in each parity of sheep; also, statistically different genetic parameters (p<0.05) were obtained from one parity to another, indicating the different and large influences of genetic and environmental factors for each parity.

Antecedentes: El tamaño de la camada al nacer (LSB) es inherentemente un rasgo categórico y debe analizarse con modelos de umbral. El LSB es uno de los rasgos de producción de carne más importantes en las ovejas y podría usarse en esquemas de mejora genética para la producción de carne. Objetivo: Se utilizaron modelos de umbral bayesiano para analizar el tamaño de la camada de ovejas al nacer (LSB) y estimar parámetros genéticos. Métodos: Los datos se basaron en 7.901 registros de LSB de 14.968 ovejas y 682 carneros recolectados de 1986 a 2012 en la estación de cría de ovejas Makouie en Irán. Se estimaron las medias de distribuciones posteriores (MPD) de los parámetros genéticos de LSB y se seleccionaron los modelos mejor ajustados utilizando el criterio de información de desviación. Resultados: En los análisis de medición repetida, la heredabilidad materna y directa estimada y el efecto ambiental permanente (±SE), según el modelo mejor ajustado (modelo 5), fueron 0,01 (0,010), 0,02 (0,014) y 0,01 (0,011), respectivamente. En el análisis univariado, las mejores estimaciones de heredabilidad directa y materna fueron 0,12 (0,064) y 0,08 (0,045), respectivamente. Se observó una tendencia creciente de heredabilidades directas y maternas en la paridad 2 (0,15 (0,082) y 0,25 (0,083), respectivamente). En el análisis bivariado, las mejores estimaciones de heredabilidad directa y materna para LSB fueron 0,03 (0,027) y 0,22 (0,041), respectivamente. Las correlaciones genéticas directas y maternas entre partos fueron 0,25 (0,054) y 0,12 (0,021), respectivamente. Conclusiones: Los resultados mostraron una influencia considerable de los factores ambientales sobre el LSB en cada parto de las ovejas; además, se obtuvieron parámetros genéticos estadísticamente diferentes (p<0.05) de un parto a otro, indicando las diferentes y grandes influencias de factores genéticos y ambientales para cada parto en ovejas. Los resultados de este estudio se pueden precisar aún más utilizando datos de SNP de todo el genoma sobre diferentes partes para manejar una amplia gama de problemas relacionados con la interacción del entorno genético del rasgo LSB.

Antecedentes: O tamanho da ninhada ao nascer (LSB) é inerentemente uma característica categórica e deve ser analisada com modelos de limiar. LSB é uma das características mais importantes de produção de carne em ovinos e pode ser usado em esquemas de melhoramento genético para a produção de carne. Objetivo: Modelos de limiar bayesiano foram usados para analisar o tamanho da ninhada de ovelhas ao nascer (LSB) para estimar parâmetros genéticos. Métodos: Os dados foram baseados em 7.901 registros LSB de 14.968 ovelhas e 682 carneiros coletados de 1986 a 2012 na Estação de Criação de Ovinos Makouie no Irã. Médias de distribuições posteriores (MPDs) dos parâmetros genéticos de LSB foram estimadas e os modelos mais bem ajustados foram selecionados usando o critério de informação de desvio. Resultados: Nas análises de medidas repetidas, as herdabilidades diretas e maternas estimadas e o efeito do ambiente permanente (±SE), de acordo com o modelo mais bem ajustado (modelo 5), foram 0,01 (0,010), 0,02 (0,014) e 0,01 (0,011), respectivamente. Na análise univariada, as melhores estimativas das herdabilidades direta e materna foram 0,12 (0,064) e 0,08 (0,045), respectivamente. Uma tendência crescente para as herdabilidades direta e materna foi observada na paridade 2 (0,15 (0,082) e 0,25 (0,083), respectivamente). Na análise bivariada, as melhores estimativas de herdabilidades direta e materna para LSB foram 0,03 (0,027) e 0,22 (0,041), respectivamente. As correlações genéticas diretas e maternas entre os partos foram 0,25 (0,054) e 0,12 (0,021), respectivamente. Conclusões: Os resultados mostraram uma influência considerável dos fatores ambientais na LSB em cada paridade de ovelhas; também, parâmetros genéticos estatisticamente diferentes (p<0,05) foram obtidos de uma paridade para outra, indicando as diferentes e grandes influências de fatores genéticos e ambientais para cada paridade em ovinos. Os resultados deste estudo podem ser ainda mais definidos usando dados SNPs de todo o genoma em diferentes partes para lidar com uma ampla gama de problemas relacionados à interação do ambiente genético do traço LSB.

RESUMO

The aim was to evaluate the pre-weaning productive performance and growth curve of Dorper*Katahdin (DPr; n = 46), Kathadin*Kathadin (KTn; n = 204) and Romanov*Kathadin (RMv; n = 40) of commercial crossed lambs from central Mexico. We considered 1450 data from 290 crossbred lambs. The variables contemplated in this study were cross (CR), lambing type (LT), sex, birth weight (BW), weaning weight (WW), test days (TD), and daily weight gain (DWG). Correlation analysis and adjustment of growth curve were performed. Differences in CR and sex were found only in BW (p < 0.05). No differences in DWG, WW, and TD (p > 0.05) by CR and sex were found. Single lambing had the highest (p < 0.05) BW, WW, and DWG. Phenotypic correlations differ among crosses. Lambs crossed with DPr presented the highest values in parameters a and b and the lowest in c. The productive behavior of DPr, KTn, and RMv cross with KTn lambs in central Mexico is similar in the pre-weaning period; however, the growth curve and parameters that characterize it suggest that DPr lambs show a tendency to enhance productive behavior in this period.

Assuntos