Flávia Oliveira Abrão

A rúcula é uma olericultura que possui relevância social, econômica e alimentar no Brasil. Destaca-se pela rápida germinação e pelo ciclo curto. A qualidade fisiológica das sementes, assim como a presença de patógenos, pode comprometer o estabelecimento inicial das plântulas. Diante do aumento no custo de insumos agrícolas e da busca por alternativas sustentáveis, microrganismos promotores de crescimento têm sido estudados como opção viável para o tratamento de sementes. Este trabalho avaliou a microbiolização de cinco tratamentos, sendo eles Bacillus subtilis, Priestia aryabhattai, Bacillus amyloliquefaciens, o MIX e o Controle sob a germinação e o vigor inicial de sementes de rúcula. O experimento foi realizado em laboratório. Os resultados da etapa de germinação mostram que a microbiolização não melhorou o desempenho na germinação das sementes de rúcula. O controle teve a maior germinação (91,5%), mas ficou estatisticamente igual ao Bacillus subtilis (89,5%). Já Priestia aryabhattai (70,5%) e o MIX (60%) apresentaram valores menores, porém também sem diferença estatística. Já o Bacillus amyloliquefaciens foi o que teve resultado bem abaixo, inclusive, igualando-se estatisticamente a Priestia aryabhattai e ao MIX. Os achados indicam que, embora a microbiolização tenha influenciado o processo germinativo, sua aplicação não resultou em melhoria do desempenho fisiológico inicial das sementes, portanto, não proporcionou ganhos compensatórios para a germinação das sementes de rúcula que superaram o controle.

Improving livestock nutrition with natural supplements can enhance productivity and meat quality. This study evaluated whether a clayey micromineral compound (CMC) in lamb diets improves feed efficiency, health, and meat traits. Twenty-four 60-day-old Dorper/Santa Inês crossbred lambs (28.41 ± 4.147 kg initial weight) were randomly assigned to four CMC doses (0%, 0.4%, 0.8%, or 1.2% of dry matter intake/day) for 90 days, following a 15-day adaptation. The lambs were individually housed, with daily feed intake monitoring, weekly weight measurements, and blood analyses at the start and end. On day 89, rumen fluid was sampled for digestion analysis, and post-mortem evaluations were used to assess meat quality and rumen health. The results showed that 0.8% CMC optimized fat and fiber digestion (p < 0.05), while higher doses linearly improved meat color intensity (p < 0.05). Blood tests indicated better liver function at intermediate doses (p < 0.05). However, the CMC did not affect overall growth, feed intake, or carcass traits. The supplement was safe but provided selective benefits. These findings suggest that CMCs could enhance feed efficiency and meat appeal, although further research is needed to refine dosing for maximum impact.

O sistema de produção de frango caipira é baseado na criação de aves comerciais para produção de carne, utilizando linhagens de crescimento lento em sistema semiextensivo. No entanto, a literatura apresenta poucas informações sobre a produção de frangos tipo caipira. O objetivo desta pesquisa foi levantar dados sobre médias de peso inicial, ganho de peso diário e peso aos 14, 21, 35, 63 e 70 dias de frangos pescoço pelado da linhagem Label Rouge®, produzidos em uma granja no município de Abadiânia, e comparar o histórico de produção com o guia de manejo da linhagem. Foram analisados 56 lotes produzidos entre janeiro de 2018 e junho de 2024, com peso inicial variando de 38,11 a 39,78 gramas. Aos 70 dias, 62,50% dos lotes atingiram a meta de peso indicada no guia de manejo, enquanto 37,50% não alcançaram o padrão recomendado. Em relação ao ganho de peso diário (GPD), embora o manual não defina essa variável, os lotes avaliados apresentaram variações de 30,61 a 35,85 gramas/ave aos 70 dias. Os resultados mostraram que, apesar do bom padrão genético das aves, elas podem atingir pesos superiores ou inferiores ao recomendado, devido às diferentes condições de manejo em cada propriedade.

Duarte ER, Lima SM, Nere JC, Freitas CES, Maia HAR, Júlio ADL, Abrão FO, Alves JMS, Santos VLD, Geraseev LC, Cota J. 2024. Yeasts isolated from bovine rumen selected to degrade lignocellulosic roughage. Biodiversitas 25: 1159-1166. Commercial yeast strains are viable alternatives to chemical additives in ruminants; however, they are not self to the rumen ecosystem. The present study was conducted to compare the degradation of Urochloa decumbens (Stapf) R.D.Webster (UD) hay and sugarcane bagasse (SB) by eight selected yeast strains, naturally present in the rumen cows and control without microorganisms. Eight yeast isolates that showed >6 log CFU per mL of ruminal fluid were selected and identified as four Pichia kudriavzevii isolates, three Rhodotorula mucilaginosa isolates and one Candida tropicalis isolate, according to their morphological and physiological characteristics and by analyses of the D1 - D2 variable domain sequences of the 28S rRNA gene. The strain V5 (R. mucilaginosa) showed higher cell biomass production than other strains of this species in fermentations with UD (P<0.05). Two isolates of Pichia kudriavzevii (V10 and V62) and one of R. mucilaginosa (V5) promoted a higher reduction of dry matter (DM) of UD than other yeast. The strain V5 was also the most efficient to reduce DM of SB (P <0.05). These selected yeasts could represent a potential alternative for use in animal diets and for industrial applications.

Commercial yeast has been frequently employed to improve the digestibility of ruminant diets, albeit these microorganisms are not indigenous to the rumen microbiome. In this investigation, our aim was to assess the in vitro digestibility of Urochloa decumbens hay (UDH) with the incorporation of two selected yeast strains isolated of ruminal fluid of Zebu cattle. Rumen fluid was collected at the onset, midpoint, and final of the dry period in a semiarid region Brazil. UDH samples were obtained from the same region. Within simulated ruminal chambers, we included McDougall buffer solution, ruminal fluid, Ankon F-57 bags containing UDH samples. Sabouraud broth (control), V62 yeast (Pichia kudriavzevii), V5 yeast (Rhodotorula mucilaginosa), or a combination thereof (mixture) were evaluated as inoculant to the ruminal fluid. The incorporation of V5, the combination of both isolates, and V5 alone resulted in significantly elevated in vitro dry matter digestibility of UDH for ruminal fluid collected at the initial, intermediate, and final stages of the dry season, respectively. Moreover, the yeast isolates demonstrated resilience to the in vitro acid digestion process, indicating their potential utility in the formulation of probiotics or microbial supplements for ruminants raised in tropical pastures during dry season.

Resumo Objetivou-se avaliar as características microbiológicas e físico-químicas do fluido ruminal e histológicas do trato gástrico intestinal (TGI) de ovinos sob dieta de alto grão com probiótico fungos Aspergillus terreus e/ou Rhizomucor spp. Analisou-se quatro probióticos (sem inóculos, com Rhizomucor spp., com Aspergillus terreus e com mistura dos dois fungos) e dois processamentos de milho (moído/inteiro), em fatorial 4x2 em em Delineamento Inteiramente Casualizados (DIC). Borregos Santa Inês/Dorper foram alojados em oito baias com cinco borregos em cada, durante 75 dias. Coletou-se fluido ruminal para o estudo do perfil microbiológico do rúmen, da característica macroscópica, da concentração de nitrogênio amoniacal e da atividade microbiológica, além dos fragmentos do TGI para análises histológicas. Pelas análises dos fluidos, os animais apresentaram baixo índice de acidose. O odor aromático e a cor castanho-enegrecido predominaram, o que caracteriza ambiente com pH neutro. As amostras do fluido apresentaram alta atividade microbiana. O pH ruminal diferenciou-se (P0,05) (bactérias Lac+ e Lac-, fungos, leveduras e protozoários). Seis gêneros de fungos anaeróbicos facultativos foram identificados num total de 15 observações. O Cladosporium spp. foi o gênero mais prevalente (46,66%), seguido do Aspergillus spp. (26,66%). A largura da base das papilas ruminais apresentou interação significativa, sendo maior para MGM (P<0,05) com Rhizomucor e o controle (P<0,05). O fluido ruminal de ovinos sob dieta de alto concentrado de grão com adição dos fungos Aspergillus terreus e Rhizomucor spp. não tiveram afetadas as características microbiológicas e físico-químicas.

This study aimed to evaluate the microbiological and physicochemical characteristics of the ruminal fluid and histological characteristics of the gastrointestinal tract (GIT) of sheep on a high-grain diet containing the probiotic fungi Aspergillus terreus and Rhizomucor spp. The study included four treatment groups (without probiotic, with Rhizomucor spp., with Aspergillus terreus, and with a mixture of both fungi), and two types of corn (ground/whole), in a Completely Randomized Design (CRD) arranged in 4 x 2 factorial design. Santa Inês x Dorper lambs were housed in eight pens with five lambs each for 75 days. Rumen fluid was collected to study the rumen microbiological profile, macroscopic characteristics, ammonia nitrogen concentration, and microbiological activity. In addition, GIT samples were taken for histological analysis. Fluid analyses showed that the animals presented a low acidosis index. The samples presented a predominantly aromatic odor and blackish-brown color, indicating a neutral pH and high microbial activity. The rumen pH differed (P < 0.05) according to the level of processed corn consumed, being higher for ground grain corn (GGC). There was no difference for any of the microbiological communities analyzed (P > 0.05) (Lac+ and Lac- bacteria, fungi, yeasts, and protozoa). Six genera of facultative anaerobic fungi were identified in 15 observations. Cladosporium spp. was the most prevalent genus (46.66%), followed by Aspergillus spp. (26,66%). The width of the base of rumen papillae showed significant correlation being greater for GCG (P < 0.05) with Rhizomucor and for the control (P < 0.05). The rumen fluid of sheep on a high-grain diet with added Aspergillus terreus and Rhizomucor spp. showed no microbiological and physicochemical changes.

The bovine production on pastures is a sustainable activity, responsible to generating income and employments in many tropical regions. However, in this system a major obstacle occurs during long dry periods, when the forages show low nutritional quality. In this research we evaluated the in vitro digestibility and degradability of Urochloa decumbens and Cynodon dactylons var Tiffton 85 inoculated with isolates of Aspergillus spp. from the gastrointestinal tract cattle. Four cows with rumen fistula were used as rumen contents donors to determine the in vitro digestibility of dry matter (IVDMD). The treatments were, as follows: control - No fungal inoculum, AT13 – (with Aspergillus terreus isolate), AF69 – (with Asperillus fumigates isolate, MIX (with mix of fungi AT13 and AF69). The analyses were performed in rumen simulator with four replications. The gas production was determined by semi-automatic method for both gas and the mechanics ability to fiber colonization of these fungi isolates were evaluated by scanning electron microscopy. The inclusion of AF69 and MIX promoted significant increase of IVDMD of U. decumbens (41.4 - 42.1%). The dry matter degradability were not influenced by the inoculums types using the by semi-automatic gas production method However, they linearly increased with fermentation time. The two isolates of Aspergillus spp. were able to colonize the U. decumbens fiber showing production of mycelium and reproductive structures in electronic microscopic analyses. The addition these Aspergillus isolates promotes significant increase of IVDMD to U. decumbens, indicating promising potential for development of microbial or probiotic additive to cattle raised on lignified tropical pasture.