Intense selection among broilers, especially for performance and carcass traits, currently favors locomotion problems and bone resistance. Conducting studies relating to development and growth of bone tissue in broilers is necessary to minimize losses. Thus, genetic parameters were estimated for a broiler population's phenotypic traits such as BW at 42 d of age (BW42), chilled femur weight (CFW) and its yield (CFY), and femur measurements: calcium, DM, magnesium, phosphorus, and zinc content; breaking strength; rigidity; length; and thickness. Variance components were estimated through multitrait analyses using the restricted maximum likelihood method. The model included a fixed group effect (sex and hatch) and additive and residual genetic random effects. The heritability estimates we obtained ranged from 0.10 ± 0.05 to 0.50 ± 0.08 for chilled femur yield and BW42, respectively, and indicated that the traits can respond to the selection process, except for CFY, which presented low-magnitude heritability coefficients. Genetic correlation estimates between breaking strength, rigidity, and traits related to mineral content indicated that selection that aims to improve the breaking strength resistance of the femur is highly correlated with mineral content. Given the genetic correlation estimates between BW42 and minerals, it is suggested that in this population, selection for BW42 can be performed with greater intensity without affecting femoral integrity.

The aim of this study was to evaluate corn grain yield and dry matter yield and nutritional value of Urochloa brizantha cv. Marandu (marandu grass) in succession to an intercrop of corn with marandu grass and/or dwarf pigeon pea (Cajanus cajan cv. Anão) in a dryland area. The experiment was conducted during the crop years of 2013/14 and 2014/15, in a low-altitude Cerrado biome (savannah) experimental area. The experiment was set up as a randomized block design with six replications, in a 2 × 2 × 2 factorial arrangement consisting of two intercrops [corn with marandu grass (CB) and corn with marandu grass and dwarf pigeon pea (CBP)]; two grain harvest times (wet and dry grain stages); and two consecutive years (2013/14 and 2014/15). Irrespective of the intercrop, the harvest of corn grain in the wet stage for silage minimized the losses caused by climatic factors. The intercrop of corn with marandu grass and dwarf pigeon pea reduced the yield of wet corn grains and the dry matter of the marandu grass in succession. Marandu grass in succession to the intercrop of corn with dwarf pigeon pea resulted in better nutritional value because of the lower fiber and higher total digestible nutrients contents.

Agronomic biofortification of staple food with zinc (Zn) in combination with diazotrophic bacteria is one sustainable and feasible strategy to improve plant nutrition, nutrient use efficiency and production and combat Zn malnutrition in human beings. Wheat (Triticum aestivum L.) is a staple food of the global population and has a prospective role in agronomic Zn biofortification. In this context, the effect of diazotrophic bacterial inoculations in seeds (no inoculation – Control, Azospirillum brasilense, Bacillus subtilis and Pseudomonas fluorescens) in association with soil Zn application (without (0) and 8 kg/ha) was evaluated on Zn nutrition, growth, yield and Zn use efficiencies in wheat in the 2019 and 2020 cropping seasons. Soil Zn application in combination with P. fluorescens improved Zn concentration in the leaf (38.8 and 45.9%), shoot (25.0 and 31%) and grain (34.0 and 33.3%) with greater shoot dry matter (9.4 and 9.9%) and grain yield (20.3 and 20.6%) as compared to controls in 2019 and 2020 respectively. Also, inoculation of P. fluorescens with Zn application improved Zn shoot and grain accumulation, zinc use efficiency, recovery and utilisation efficiency. With daily wheat consumption, these improvements would be associated with a with higher estimated Zn intake for the human population globally and within Brazil. However, agro-physiological efficiency was increased with inoculation of Bacillus subtilis. Therefore, inoculation of P. fluorescens in association with soil Zn application is recommended for agronomic biofortification, and to increase productivity and Zn use efficiencies in wheat in the tropical savannah of Brazil.

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The objective of this work was to evaluate the characteristics of the maternal-offspring behavior of Guzerat bovines (Bos indicus) and the influence of this behavior on herd losses. A total of 73 gestating cows (multiparous and primiparous) and their respective calves were evaluated for the following behavioral traits: contact period between cow and calf (CPCC), cow age at calving, teat conditions, calf vigor at birth, need for human assistance (HA), and calf mortality until weaning. The mean weight of calves at birth was 29.12 kg. Vigor at birth was observed in 61.64% of calves; however, 27.4% of the calves required human assistance. Calf vigor was influenced by the CPCC, and calves without vigor needed more time with their mothers. Calves with low weight at birth required HA, whereas calves from cows with intermediate-sized teats did not. The absence of vigor at birth increased the mortality rate. The traits age of cows and vigor of calves at birth influence both the need for human assistance to calves in their first hours of life and herd losses.

The objective of this work was to estimate genetic parameters for traits related to resistance to endoparasites in Santa Inês sheep, for a possible inclusion in sheep breeding programs, as well as to evaluate the additive genetic pattern of the animals using cluster analyzes, in order to assess whether there are groups within the population that can be used as candidates for selection for resistance to endoparasites. The studied traits were: Famacha score, fecal egg counts (FEC), packed cell volume (PCV), total plasma protein (TPP), body condition score (BCS), and body weight (BW). Heritability estimates ranged from 0.17 (0.05) for TPP to 0.31 (0.07) for BCS. The cluster analyzes based on the breeding values identified four clusters. Famacha and BCS can be recommended as selection criteria for resistance to hematophagous endoparasites because they can respond to selection and are easy to be measured. Animals from cluster 1 have great potential as candidates for selection because of their additive genetic pattern, taking into account body weight and endoparasite resistance due to higher breeding values for BW, BCS, PCV, and TPP and lower breeding values for Famacha and FEC.

The objective of this study was to develop a bio-economic model for the estimation of economic values of economically important traits in a full-cycle beef cattle production system. The bioeconomic model calculated economic values by simulating the impact of changes in the profit of the system consisting of a 1% increase in each trait of the breeding objective, while the other traits were kept constant. The bio-economic model was effective in estimating the sources of revenues and expenses of the production system. The estimated economic values were, in the order of importance for the full-cycle system, R$ 3.69 for male slaughter weight, R$ 3.63 for male weaning weight, R$ 3.58 for weaning rate, R$ 3.40 for female slaughter weight, R$ 2.30 for female weaning weight, and R$ 0.13 for mature cow weight. The results showed that all traits evaluated in the full-cycle system had positive economic impact, indicating that selection would increase profitability maximizing the expected response for the traits of the breeding goal.

Context Agronomic biofortification of wheat (Triticum aestivum L.) with zinc (Zn) is an effective approach to increase grain Zn concentration and productivity and alleviate Zn malnutrition in humans. Foliar Zn application is an alternative strategy to endorse soil Zn deficiency with better grain Zn partitioning. Aims This study aimed to better understand dose management of soil and foliar Zn application in wheat for biofortification. Methods The objectives was to evaluate the effect of foliar applied nano Zn doses (0, 0.75, 1.5, 3 and 6 kg/ha (zinc oxide, ZnO) 50% at tillering and 50% at grain filling in combination) with soil Zn application (0 and 8 kg/ha, as zinc sulfate) on growth, nutrition, Zn use efficiencies, intake and yield biofortification of wheat in 2019 and 2020 under Brazilian savanna. Key results Combined foliar and soil Zn application increased shoot and grains Zn concentration and accumulation with greater dry matter (9.8 and 10.6%) and grain yield (9.8 and 11%) of wheat as compared to control in 2019 and 2020 respectively. Zinc use efficiency (ZnUE), Zn utilisation efficiency and applied Zn recovery improved with soil Zn application and 2.5 kg/ha foliar nano Zn, but decreased with further increase in foliar Zn application. Zn sulfate stood out for increasing crop productivity while foliar spray with nano Zn for better grains biofortification of wheat. Conclusions Soil Zn application along with 3 kg/ha of foliar nano Zn increased plant and grains Zn concentration and accumulation, dry matter, grain yield, Zn partitioning index and Zn intake in wheat in tropical conditions of Brazil. Implications The combined application of soil and foliar Zn in harsh tropical savannah condition could better improve Zn nutrition, crop growth, and productivity with better Zn biofortification and intake of wheat.