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    Associação genética entre características de carcaça, crescimento e de reprodução em bovinos braford e brangus
    (Universidade Federal de Mato Grosso, 2021-02-22) Zuim, Deise Mescua; Bignardi, Annaiza Braga; 283.733.228-33; http://lattes.cnpq.br/5149653630729211; Santana Júnior, Mário Luiz; 067.921.646-40; http://lattes.cnpq.br/9205633142085534; Santana Júnior, Mário Luiz; 067.921.646-40; http://lattes.cnpq.br/9205633142085534; Bignardi, Annaiza Braga; 283.733.228-33; http://lattes.cnpq.br/5149653630729211; Pereira, Rodrigo Junqueira; 061.788.896-58; http://lattes.cnpq.br/5707957381561914; Menezes, Gilberto Romeiro de Oliveira; 058.807.516-78; http://lattes.cnpq.br/9971427968154736
    The study was developed with the objective of estimating the genetic association between growth, reproduction and carcass traits obtained by ultrasound in Braford and Brangus cattle. Longissimus muscle area (LMA), and backfat thickness (BFT), postweaning average daily weight gain (ADG), visual scores of conformation (C), precocity (P), muscling (M), size (S), scrotal circumference (SC) at around 420 and 550 days of age, and days to first calving (DFC). The heritability estimates obtained were of moderate magnitude for LMA (0.23 to 0.27) and low for BFT (0.07 to 0.16), supporting the possibility of a favorable response to selection, especially LMA. The most favorable genetic correlations found for visual scores were between P550 and LMA (0.39 to 0.51) and between M550 and LMA (0.32 to 0.41) for Braford, and for Brangus they were between P550 and LMA420 or LMA550 (0.56) and between M550 and LMA (0.17 to 0.51). Estimates of genetic correlation between BFT and P550 were positive and of moderate to high magnitude for Braford (0.33 to 0.58) and Brangus (0.26 to 0.61). The genetic associations between SC and LMA were of low magnitude, however stronger when SC was measured around 550 days for Braford (0.12 to 0.30) and Brangus (0.01 to 0.21). Between SC and BFT, the genetic correlations varied from -0.18 to -0.12 for Braford and from -0.26 to 0.42 for Brangus. There was evidence of a favorable genetic relationship of DFC with LMA (- 0.22 to -0.12) and BFT (-0.26 to -0.22) at different ages in Braford cattle, the same was not observed for Brangus for LMA (0.03 to 0.29) and BFT (0.04 to 0.57). In view of the differences in estimates of genetic correlation between breeds and measurement ages of animals, it is necessary to develop specific selection strategies for each case.
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    Associação genética entre habilidade de permanência no rebanho em partos consecutivos e características de interesse econômico em bovinos nelore
    (Universidade Federal de Mato Grosso, 2021-02-26) Morales, Débora da Silva; Pereira, Rodrigo Junqueira; 061.788.896-58; http://lattes.cnpq.br/5707957381561914; Pereira, Rodrigo Junqueira; 061.788.896-58; http://lattes.cnpq.br/5707957381561914; Santana Júnior, Mário Luiz; 067.921.646-40; http://lattes.cnpq.br/9205633142085534; Bignardi, Annaiza Braga; 283.733.228-33; http://lattes.cnpq.br/5149653630729211
    The trait stayability (STAY) is a way of assessing the female's longevity potential. Measuring the STAY to each cow calving would allow obtaining earlier indicators of longevity. The objective with the present study was to estimate genetic parameters for STAY in consecutive calvings, age at first calving (AFC), days to calving (DC), weaning weight (WW), and yearling weight (YW); the possible genetic association between the STAY in consecutive calvings and AFC, DC, WW and YW; the influence of the animals genetic potential for the traits AFC, DC, WW and YW in the chances of selection for STAY in consecutive calvings in Nellore cattle. The estimation of variance components and subsequent prediction of breeding values was performed through single-trait analyzes. The estimated breeding values (EBV) were then used to analyze the association between STAY and the other traits. For HPR in consecutive calvings, the heritability estimates ranged from 0.02 to 0.06, with an increasing magnitude according to the calving number. For the traits AFC, DC, WW (direct and maternal effects), and YW, the heritability estimates were 0.07, 0.02, 0.17 and 0.08, 0.33, respectively. Genetic correlation estimates between STAY in different calvings ranged from 0.58 to 0.94 and were higher between closer calvings. The correlation estimates between EBV of the intercept coefficient for STAY in consecutive calvings and EBV of AFC, DC, WW (direct and maternal effects), and YW were -0.14, -0.08, 0.05 and 0.005, 0.07, respectively. The influence of genetic potential of reproductive traits on the odds ratio of selection for STAY in consecutive calvings resulted in a decrease in the chance of selection for STAY in all calvings studied when the EBV for AFC or DC were increased. The WW (direct effect) positively influenced the selection for STAY initially and negatively influenced it at the end of the cow's reproductive life. The WW (maternal effect) positively influenced the scenario with greater selection intensity and negatively influenced it in the other scenarios. For the YW, an increase in genetic potential increased the chances of selection for STAY, except for the later calvings of the scenario with greater selection intensity.
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    Disponibilidade hídrica no solo e intervalo após a calagem para implantação de gramíneas forrageiras
    (Universidade Federal de Mato Grosso, 2021-02-26) Gregório, Francisco Cidnei; Cabral, Carlos Eduardo Avelino; 019.717.471-06; http://lattes.cnpq.br/6739111102181898; Leão, André Gustavo; 290.547.528-58; http://lattes.cnpq.br/7286596323526732; Leão, André Gustavo; 290.547.528-58; http://lattes.cnpq.br/7286596323526732; Cabral, Carlos Eduardo Avelino; 019.717.471-06; http://lattes.cnpq.br/6739111102181898; Abreu, Joadil Gonçalves de; 830.338.746-49; http://lattes.cnpq.br/1410481664723748; Carvalho, Kassio dos Santos; 019.614.551-10; http://lattes.cnpq.br/6803860677169308
    In tropical conditions, the correction of soil acidity is an important step in the process of implanting forages, being essential for success in the pasture formation. However, the need for intervals between application of lime and sowing of more than 60 days occupy a considerable part of rainy season and can compromise the establishment pasture. Although it involves time, the reaction of the limestone in the soil is dependent on the soil water availability, and the faster the greater the presence of water interacting with the CaCO3 of the limestone. In this work, the objective was: (1) to verify if it is possible for acidity correction to occur in less than 60 days after the incorporation of limestone; (2) what soil water availability is necessary for acidity correction to occur in less than 60 days. For this, two experiments were carried out in a greenhouse in Rondonópolis-MT with a completely randomized design in a factorial scheme. In the first experiment, 8 treatments were evaluated, obtained from the combination of the number of times the soil was raised to the maximum water retention capacity (1, 2, 3 and 9 irrigations) and two expected base saturations (50 and 60 %). Dolomitic lime (calcium oxide: 31%, magnesium oxide: 21%, neutralizing power: 107%, RE: 80.4% and total relative neutralizing power: 86%) was used to raise base saturation. The pH and aluminum saturation of the soil, before liming, were 4.1 and 75%, respectively. Forty-five days after the incorporation of the lime, chemical analysis of the soil was carried out and sowing of the cultivar BRS RB331 Ipyporã (Brachiaria brizantha x Brachiaria ruziziensis). The soil pH (CaCl2) was raised to values above 5.0 in all treatments. Irrigations number did not affect the saturation of toxic aluminum in the soil, however, there was a reduction in aluminum saturation from 75.0 to 3.5%. Beside, irrigations number did not alter the development of the grass and a single irrigation, increasing the soil moisture for maximum water retention capacity, corrected the acidity of the soil and made it possible to reduce the interval between liming and sowing to 45 days. Second experiment was carried out with the cultivar Mombasa (Panicum maximum), in which 6 treatments were adopted in a 3x2 factorial scheme, constituted by the combination of three soil water availability (50, 75 and 100% of the maximum water retention capacity in the soil) and two lime reaction periods (30 and 60 days). Soil water availability changed the lime reaction time. Results of the soil analysis indicated that thirty days after liming, with a precipitation capable of raising the soil moisture to 50% of the maximum water holding capacity, chemical changes occurred in the soil, so that the main one was the absence of toxic aluminum. However, for implantation of the pasture 30 days after liming, it is necessary a precipitation that provides the elevation of the soil moisture to 75% of the maximum soil water retention capacity.
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    Efeito do consórcio de gramíneas com feijão-caupi na entressafra sobre a produção de bovinos de corte
    (Universidade Federal de Mato Grosso, 2021-08-20) Mattos, Jenifer Santos de; Silva, Francine Damian da; 009.510.500-01; http://lattes.cnpq.br/9838212017844050; Cabral, Carlos Eduardo Avelino; 019.717.471-06; http://lattes.cnpq.br/6739111102181898; Cabral, Carlos Eduardo Avelino; 019.717.471-06; http://lattes.cnpq.br/6739111102181898; Cabral, Carla Heloisa Avelino; 718.096.431-04; http://lattes.cnpq.br/0254810575145100; Silva, Francine Damian da; 009.510.500-01; http://lattes.cnpq.br/9838212017844050
    Legumes use intercropped with grasses is advantageous mainly due to the assimilation of atmospheric nitrogen carried out by the legumes, which reduces the demand for nitrogen fertilizers, as well as increasing the nutritive value of pasture. Therefore, in intercropped cultivation, legumes that are not antagonistic to grasses must be selected, in order to compromise the system's productivity. One possibility for use in pastures is the use of cowpea (Vigna unguiculata) and, therefore this research aimed to identify whether cowpea offers an increase in animal performance when intercropped with grasses in the off season. Experiment was carried out in the municipality of Itiquira, Mato Grosso, in a randomized block design, in a 4x2 factorial scheme. The treatments consisted of four grasses cultivation (Urochloa ruziziensis cv. Kennedy, Urochloa brizantha cv. Paiaguás, Urochloa brizantha cv. Piatã and Panicum maximum cv. BRS Tamani) in two systems (monoculture and intercropping with cowpea cv. BRS Tumucumaque) in the off-season of 2016 and 2017. Systems were sown in succession to soybeans (March), and the animals entered the area in May. Samples were collected in May, June and July to measure forage mass, morphological, botany and chemical-bromatological composition. The intercropping of grasses with cowpea provided an increase in stocking rate for Tamani and Paiaguás grasses, compared to the monoculture system. Furthermore, the intercropping with cowpea provided an increase in weight gain per area in all grasses, except for Piatã grass. In addition, pastures with cowpea had higher crude protein content, with the exception of Paiaguás. Also, all the grasses tested can be used in the off-season in succession to soybean and the intercropping of grasses with cowpea, in general, increases the performance of beef cattle during the off-season.
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    Estratégias de adubação no controle de plantas daninhas em sistemas integrados de produção agropecuária
    (Universidade Federal de Mato Grosso, 2022-04-01) Correia, Éder Sequini; Souza, Edicarlos Damacena de; 719.200.561-49; http://lattes.cnpq.br/6843055362772781; Pacheco, Leandro Pereira; 986.520.871-72; http://lattes.cnpq.br/4926743824358076; Pacheco, Leandro Pereira; 986.520.871-72; http://lattes.cnpq.br/4926743824358076; Souza, Edicarlos Damacena de; 719.200.561-49; http://lattes.cnpq.br/6843055362772781; Silva, Laércio Santos; 088.056.464-40; http://lattes.cnpq.br/4950965911726118
    The objective of this work was to evaluate the effect of NPK fertilization strategies on pasture and soybean crop in integrated agricultural production systems (LPIS) as a possible way to control weeds and their effects on animal weight gain and soybean productivity. The experiment was established in 2020 with the sowing of pasture (Urochloa brizantha, cv. BRS Piatã) after the harvest of the soybean crop (Glycine max, cv. BRASMAX Ultra IPRO) which is implanted annually in October in a no-tillage system. The experimental design was in randomized blocks, with four fertilization strategies: (1) conventional fertilization (phosphate and potassium in the soybean crop AC - N), (2) conventional fertilization + nitrogen fertilization in the pasture (AC + N), (3) Pasture fertilization (phosphate and potassium in the AP - N pasture phase) and (4) System fertilization (phosphate, potassium and nitrogen in the AS pasture phase). The amounts of fertilizers applied were 100 kg of nitrogen ha-1 (320 kg ha-1 of ammonium nitrate) in a single dose on the pasture, the phosphate and potassium fertilization was 72 kg of P2O5 ha-1 and 90 kg of K2O ha-1. The height of the pasture was regulated by means of rotational grazing and variable stocking rate in the treatments, with an average of 3.5 AU/ha, of Nelore beef steers aged 13 to 24 months, entry with 40 cm of height. of the pasture, on 03/21/2020, removed 30 cm high from the pasture, on 07/17/2020. In the treatments that were carried out with the fertilization of NPK (AS) and PK systems without N in the pasture phase (AP-N), there was a significant reduction in the population and phytomass of the four main weed species collected: Digitaria horizontalis (Capim-colchão), Eleusine indica (Chen-foot grass), Chamaesyce hirta (Santa Luzia herb), Cyperus aggregatus (Cyperus). Nitrogen fertilization as a weed management strategy and increases in animal and soybean production is only justified when phosphate and potassium fertilization is applied in the crop phase. Fertilization of NPK systems on pasture increases soybean productivity, while animal weight gain is higher with PK fertilization on soybean with N on pasture. The repositioning of phosphate and potassium fertilization in the pasture phase is sufficient for the management of weeds both in the pasture and in the crop phase.
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    Interação genótipo ambiente devido ao estresse térmico durante o final da gestação sobre caraterísticas de crescimento de bovinos de corte
    (Universidade Federal de Mato Grosso, 2021-02-25) Alves, Mariana Stucki; Santana Júnior, Mário Luiz; 067.921.646-40; http://lattes.cnpq.br/9205633142085534; Bignardi, Annaiza Braga; 283.733.228-33; http://lattes.cnpq.br/5149653630729211; Bignardi, Annaiza Braga; 283.733.228-33; http://lattes.cnpq.br/5149653630729211; Santana Júnior, Mário Luiz; 067.921.646-40; http://lattes.cnpq.br/9205633142085534; Pereira, Rodrigo Junqueira; 061.788.896-58; http://lattes.cnpq.br/5707957381561914; Zadra, Lenira El Faro; 115.329.428-18; http://lattes.cnpq.br/5118853929961241
    The effect of thermal stress on production traits has been widely studied in cattle. However, the effect of heat stress that females undergo during pregnancy can compromise embryonic nutrition, fetal and placental development, cause a reduction in gestation length, and impair calves' postnatal performance. Thus, this study aimed to estimate genetic parameters associated with thermal stress during late pregnancy for birth weight (BW) and average daily weight gain from birth to weaning (ADG) of Braford and Brangus cattle. The data refer to 73,383 animals of the Braford breed and 45,120 of the Brangus breed, with birth dates between 1974 and 2017. The calves were weighed at birth and at the time of weaning, which occurred around 205 days of age. The average temperature and humidity index (ITU) was calculated over the last days of gestation (60, 70, 80, and 90) for each animal in the analysis. The mean ITU of the final pregnancy period (ITUg) was included in the fixed linear model. The least-squares means (LSM) were calculated for BW and ADG on each ITUg variable to be evaluated. A regression model was applied on the LSM to assess the BW and ADG response pattern in the function of each ITUg. For Braford and Brangus, the fixed model considering the ITUg calculated over 60 days and 70 days before calving, respectively, presented the highest R2 . During the final gestation period, heat stress significantly reduced both the BW and the ADG of the Braford and Brangus cattle. The ADG was reduced by -00021 and -0,0013 kg/ day / ITUg for Braford and Brangus, representing an expressive productive and economic loss for the studied populations. The heritability estimates for the direct effect for BW varied for Braford from 0,35 to 0,62 with an average of 0,45. For Brangus, the estimates were from 0,26 to 0,52 with an average of 0,37. For the maternal effect, they ranged from 0,06 to 0,17 for Braford and 0,07 to 0,35 for Brangus, with a mean of 0,10 and 0,16 respectively. The heritability estimates for direct and maternal effects were 0,07 to 0,27, with a mean of 0,14, and 0,11 to 0,19, with an average of 0,14, respectively for ADG of Braford cattle. These estimates demonstrate substantial heterogeneity of genetic variances along the environmental gradient. The genetic correlations between the same trait in adjacent ITUg values were of high magnitude. However, among extreme and opposite ITUg they were low or even negative, especially for BW. Therefore, the inclusion of this effect in genetic evaluations to identify and select animals genetically more tolerant to thermal stress becomes justified due to its reflexes on the animal's future performance.
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    Suplemento proteico e monensina para bovinos em pastejo no período das águas
    (Universidade Federal de Mato Grosso, 2021-02-24) Coutinho, Marina Pereira Souza; Cabral, Carlos Eduardo Avelino; 019.717.471-06; http://lattes.cnpq.br/6739111102181898; Cabral, Carla Heloisa Avelino; 718.096.431-04; http://lattes.cnpq.br/0254810575145100; Cabral, Carla Heloisa Avelino; 718.096.431-04; http://lattes.cnpq.br/0254810575145100; Souza, Alexandre Lima de; 816.861.706-10; http://lattes.cnpq.br/2182780077626286; Barros, Livia Vieira de; 073.193.606-08; http://lattes.cnpq.br/9490340357962289
    Two experiments with crossbred heifers (Nellore breed predominance) under grazing during the rainy season were carried out with the objective of evaluate the effect of monensin inclusion on protein and mineral supplements on productive performance, pasture consumption, dry matter intake and nutrient digestibility, as well as to identify changes in the ingestive behavior of heifers, thermal comfort and its relationship with ingestive behavior through the Index of thermal stress for cows (ITSC) in grazing. The experimental area consisted of 7 hectares of Brachiaria brizantha cv. Marandu under continuous stocking, located in Rondonópolis-MT. In both experiments, a 2x2 factorial scheme and a completely randomized design were adopted. The first experiment was carried out from December 2015 to March 2016. The treatments consisted of two protein supplements (high and low consumption) and the inclusion or not of monensin. Productive performance, nutrient consumption and digestibility were evaluated. Forty heifers with an average initial weight of 213.8 ± 4.5 kg were used. There was no difference (P>0.05) in the animals' performance among treatments, with an average daily gain of 0.588 kg animalday -1 . There was no interaction (P<0.05) between sodium monensin and supplements for consumption and digestibility variables, except for crude protein (CP) digestibility. There was equality in the dry matter (DM) intake among treatments (± 2% of the animals' body weight). However, there was a reduction (P<0.05) in pasture intake with the high consumption supplement, showing a substitutive effect. There was no treatments effect on the digestibility parameters (P> 0.05), but a greater CP digestibility (P<0.05) was observed when monensin was associated with low-consumption protein. It was concluded that monensin does not improve the performance of grazing heifers by consuming high and low consumption protein supplements, and its use is dispensable. The second experiment was carried out from December 2016 to March 2017. The treatments consisted of two supplements (mineral and protein) and the inclusion or not of monensin. Forty heifers with an average age and initial weight of 9 months and 159.2 ± 1.3 kg, respectively, were used. There was no interaction (P> 0.05) between the supplement type and monensin and there was no influence (P> 0.05) of the supplement type on the animals' performance. However, monensin promoted greater (P <0.05) weight gain of the animals (± 107 ganimal.day-1 ). There was an interaction (P <0.05) between supplementation and monensina inclusion on behavioral activities, except for idle time. There was equality in the average grazing time (455 minutes) of animals that received mineral supplement, regardless of the monensin inclusion. The monensin inclusion in the protein supplement reduced (P <0.05) the grazing time by 45 minutes. The ITSC value influenced (P <0.05) the ingestive behavior and the increase of this index reduced the grazing time in all treatments. Monensin improves the weight gain of animals grazing tropical forages under continuous stocking management.