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Criação e manejo de Xylocopa frontalis e sua utilização comparativa na polinização do urucuzeiro (Bixa orellana)

Thu, 01 Jan 2026 00:00:00 GMT

Título: Criação e manejo de Xylocopa frontalis e sua utilização comparativa na polinização do urucuzeiro (Bixa orellana) Autor(es): Silva, Felipe Jackson de Farias Abstract: We aimed to propose improvements to a rational nest model for bees of the genus Xylocopa, especially X. frontalis, as well as techniques for the rearing, multiplication, and management of this species, and its efficiency as a pollinator of the annatto tree (Bixa orellana), compared to three other native bee species (Augochloropsis sp., Melipona fasciculata, and Melipona flavolineata). The first colonized nests appeared few months after their installation in the study area. The number of galleries built per nest ranged from one to six (3.82 ± 1.4). The galleries had a total average length of 104.19 (±43.41) cm and an excavated volume of 327.15 (±136.29) cm³. Active nests were observed throughout the study period and were transported and relocated without abandonment. Regarding pollination, peak flower visits occured between 7:00 and 8:00 AM, with X. frontalis foraging earlier than other bees and making shorter flower visits. No statistically significant differences were detected in any fruit parameters between treatments. The treatment with free pollination showed the highest fruit set rate (37.5%), followed by a visit from M. flavolineata (25%), although no statistically significant difference was observed. We conclude that our rational nesting device is a suitable alternative for the rearing and management of Xylocopa frontalis and, presumably, other species of the genus for crop pollination or research purposes, without evidence of negative interference in the nesting biology of these bees. Xylocopa frontalis proved to be an efficient pollinator of Bixa orellana. Tipo: Tese

In silico molecular characterization of cholesterol binding to species-specific and non-specific albumins and their effects on in vitro quality parameters of ram spermatozoa

Wed, 01 Jan 2025 00:00:00 GMT

Título: In silico molecular characterization of cholesterol binding to species-specific and non-specific albumins and their effects on in vitro quality parameters of ram spermatozoa Autor(es): Pessoa, Eduardo Rodrigues Abstract: In the present study, the interactions of cholesterol (CHOL) with bovine (BSA), human (HSA), ovine (OSA) and caprine (CSA) albumins were analyzed using in silico approaches (docking, molecular dynamics, and quantum biochemical calculations). A sequential, in vitro experiment evaluated the effects of species-specific (OSA) and non-species-specific (BSA, HSA and CSA) albumins on ram sperm. In this case, semen collected from 10 rams were mixed with extender, aliquots were subjected to cooling for 3 (15 °C) and 24 hours (5 °C), and incubated with TALP medium and BSA, HSA, OSA or CSA (5 mg/mL). Overall, OSA combines energetically favorable poses with stable complexes for CHOL interaction, especially at FA1-FA9 and FA1 sites. FA1 was present in three of the four albumins, supporting its relevance as a CHOL binding site. Although molecular docking ranked HSA highest and molecular dynamics simulations highlighted CSA’s rigidity at FA6/NS5 sites, OSA was a more consistent CHOL binder after evaluations with all methods. In 3-hour cooled samples, OSA decreased total sperm motility (44 ± 2.4 %; p < 0.05) compared to the control, BSA, HSA, and CSA groups (76.1 ± 3.8, 81.3 ± 4.1, 72.8 ± 3.4, and 70.3 ± 4.2 %). OSA reduced sperm viability (28.8 ± 5.3 %; p < 0.05) compared to control (50.1 ± 4.2 %), with intermediate values in BSA, HSA, and CSA groups. Apoptosis or mitochondrial functionality were not affected by treatments. Acrosome-reacted spermatozoa were higher in OSA (40.2 ± 3.5 %; p < 0.05) compared to control and BSA (24.4 ± 1.6 and 23.5 ± 1.4 %), with HSA and CSA showing intermediate results. In 24-hour cooled samples, OSA reduced sperm motility (48.8 ± 3.8 %; p < 0.05) in comparison with BSA (72.2 ± 4.5 %). OSA decreased sperm viability (21.9 ± 1.6 %; p < 0.05) compared to control and BSA (40.3 ± 2.4 %), while HSA and CSA groups had intermediate values. Apoptosis was higher in OSA and mitochondrial functionality was enhanced by BSA and HSA compared to OSA. Treatments with HSA and OSA had greater acrosome reaction rates in ram spermatozoa (35.1 ± 2.3 and 30.8 ± 1.4 %; p < 0.05) than in control (19.2 ± 4.2 %), while BSA and CSA showed intermediate results. Thus, capacitation-related changes were pronounced with species-specific albumin, partially explained by energetically favorable OSA–CHOL binding (shown by in silico analyses). OSA significant effects on sperm acrosome reaction compromised sperm motility, viability and mitochondrial function, especially after prolonged cooling. Within the ovine model, OSA represents a promising alternative to BSA in capacitation systems. However, OSA concentrations and incubation parameters need to be optimized to balance capacitation induction with sperm preservation Tipo: Tese

Vitamina D associada a antioxidantes e vitamina K3 na alimentação de frangos de corte

Sun, 01 Jan 2023 00:00:00 GMT

Título: Vitamina D associada a antioxidantes e vitamina K3 na alimentação de frangos de corte Autor(es): Melo, Marcelle Craveiro Abreu de Abstract: This study aimed to evaluate the effects of vitamin D supplementation associated with antioxidants and vitamin K3 in the diet of broiler chickens on productive aspects, meat quality, incidence of pectoral myopathies, bone quality, black bone syndrome and oxidative status of the serum, liver and chicken breast meat. A total of 768 one-day-old male chicks of the Ag Ross 308 strain were used, distributed in a completely randomized design, with eight treatments and six replications of sixteen birds each. The treatments consisted of eight feeds formulated to be isoenergetic and isonutritive: T1 – Control diet (CD); T2 – CD + Vitamin D; T3 – CD + Vitamin D + Antioxidant A; T4 – CD + Vitamin D + Antioxidant B; T5 – CD + Vitamin D + Antioxidant C; T6 – CD + Vitamin D + Vitamin K3; T7 – CD + Vitamin D + Vitamin K3 + Antioxidant B and T8 – CD + Vitamin D + Vitamin K3 + Antioxidant C. The vitamin D metabolite used was 25OHD3 (1836 IU/kg) and for vitamin K3, menadione nicotinamide bisulfite (0.63 mg/kg) was used. There was no significant difference between treatments for performance, carcass yield, total phenolics, antioxidant capacity and oxidative stability of serum and liver of birds. There was also no significant effect of additive supplementation of Vit. D, Vit. K3 and antioxidants on meat quality and bone quality as well as no influence of additives was also observed on total phenolics, antioxidant capacity, total antioxidant activity and lipid stability of meat. The interrelation of Vit. D with antioxidants and Vit. K3 did not negatively affect the incidence of pectoral myopathies and black bone ndrome. It is concluded that the associated use of these additives in the diet of broiler chickens does not affect the productive aspects, the quality of the meat, the incidence of pectoral myopathies, the bone quality, the incidence of black bone syndrome and the oxidative status in the meat and in the body of broiler chickens. Tipo: Tese

Traces elements requirements for hair sheep: a multi-study Approach

Mon, 01 Jan 2024 00:00:00 GMT

Título: Traces elements requirements for hair sheep: a multi-study Approach Autor(es): Justino, Evandra da Silva Abstract: The success of ruminant production in tropical regions largely depends on the productive potential of the animals and their ability to adapt to environmental conditions. Microminerals are involved in many functions of metabolism. The dietary requirements of each mineral correspond to the sum of the net requirements for maintenance and production and the result is divided by the absorption coefficient of the mineral in the animal's digestive tract. However, not every mineral absorbed by the animal has a function in the body. Thus, the use of the absorption coefficient does not seem to be the most appropriate method, but the true retention coefficient, which considers mineral losses via urine. Sex class is involved in animal physiology and metabolism and has effects on growth, body composition, and productive and reproductive functions. As with protein and energy, the sex modulates mineral dynamics and, in consequence, mineral deposition in the animal’s body. The objective of this study was to evaluate the micromineral requirements of Cu, Fe, Mn, Zn, Co, and Cr for gain and maintenance for hair sheep. The dataset consists of 248 individual records (139 non-castrated, 75 castrated males, and 34 females) compiled from six studies. The meta-analytical approach was used, employing non-linear mixed-effects models. These selected models account for the observed variability among the sexes, based on a low level of uncertainty (w⩾0.90). The net mineral requirement for maintenance and retention coefficient were 0.03485 mg/kg of BW and 23% for Cu; 0.03963 mg/kg of BW and 13% for Fe; 0.00611mg/kg of BW and 0,7% for Mn; 0.194 mg/kg of BW and 28.7% for Zn; 0.00606 mg/kg of BW and 13.8 % for Co; 0.011 mg/kg of BW and 8.6% for Cr, respectively. The net iron requirement for gain decreased with increasing BW from 10 to 30 kg and average daily gain (ADG) of 150 g/day, ranging from 11.54 – 8.93; 10.58 - 6.81; 7.16 - 2.91 mg of Fe for intact males, castrated males, and females, respectively. Intact males followed by females had higher Mn requirements than castrated males. Castrated males had a higher requirement for chromium compared to males and females during growth. The micromineral requirements of this study are relevant for the development of feeding systems for hair sheep, and for optimizing mineral nutrition management of males and females during the growing phase. Tipo: Tese