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Blend enzimático em dietas para leitões na fase de creche

2026-03-04T13:10:18Z

Título: Blend enzimático em dietas para leitões na fase de creche Autor(es): Patrício, Ivyna Dryelle Fernandes Abstract: With the aim of improving nutrient digestibility, the use of exogenous enzymes can also provide nutritional and/or energy increase in diets for piglets. The objective was to evaluate the addition of an enzyme blend to diets for piglets in two trials regarding the digestibility of feed nutrients, performance, occurrence of diarrhea and intestinal morphometry. In both trials, 4 treatments were used: CON- control feed; RED5- feed with a 5% reduction in energy level, RED2.5%+blend- ration with a 2.5% reduction in energy level and addition of an enzymatic blend; RED5+blend- ration with 5% reduction in energy level and addition of enzyme blend. For the digestibility test, 16 castrated male pigs aged 50 days were housed in metabolic study cages, using the total feces and urine collection method. The addition of an enzymatic blend with a 2.5% energy reduction results in higher digestibility coefficients for dry matter, ether extract, mineral matter, neutral detergent fiber and acid detergent fiber. For the performance test, 64 castrated male piglets aged 21 days were used, distributed among 4 treatments with 8 replications each. From 33 to 42 days of age, it was observed that piglets fed diets with the addition of an enzyme blend showed similar feed conversion compared to those fed the control. Between 43 and 70 days of age, piglets that received diets with the addition of an enzyme blend and reductions of 2.5% in the energy level of the diet showed similar feed conversion to animals that received the control diet. Animals that received food with an enzyme blend showed greater villus height in the duodenum compared to animals fed control food and with a 5% reduction without enzyme supplementation. Animals that received feed containing an enzyme blend showed higher villus height, lower crypt depth and a better villus/crypt ratio compared to those fed with feed with a 5% reduction in energy level without the addition of enzyme blend. The inclusion of an enzymatic blend allows a reduction of up to 2.5% in the energy level of diets without compromising the performance of piglets in the nursery phase and results in better parameters of intestinal morphometry of the duodenum and jejunum of piglets. Tipo: Dissertação

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

2026-02-09T13:16:06Z

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

Efeito do pastejo por ovinos sobre a composição florística da vegetação herbácea de uma caatinga raleada

2026-01-08T12:09:02Z

Título: Efeito do pastejo por ovinos sobre a composição florística da vegetação herbácea de uma caatinga raleada Autor(es): Araújo Neto, Raimundo Bezerra de Tipo: Dissertação

Valor nutritivo e efeito de diferentes níveis de feno de Leucena (Leucaena leuco cephala (LAM.) de Wit) sobre o consumo e digestibilidade das rações

2026-01-21T20:49:53Z

Título: Valor nutritivo e efeito de diferentes níveis de feno de Leucena (Leucaena leuco cephala (LAM.) de Wit) sobre o consumo e digestibilidade das rações Autor(es): Costa, Emanuel Sousa Abstract: This research was conducted in the Departamento de Zootecnia do Centro de Ciências Agrarias da Universidade Federal do Ceara in order to determine the nutritive value of Leucaena leucocephala (LAM.) de WIT, hay, the effect of different levels of that hay on both apparent digestibility and intake and to test different methods of apparent digestibility determination. [...] Tipo: Dissertação