https://repositorio.ufra.edu.br/jspui/handle/123456789/1172 Doutorado em Reprodução Animal na Amazônia 2026-04-12T08:24:07Z https://repositorio.ufra.edu.br/jspui/handle/123456789/2656 Título: Aspectos reprodutivos de uma população de guará (Eudocimus ruber) sob cuidados humanos em baixa latitude. Autor(es): GONZÁLEZ GONZÁLEZ, Camilo Andrés Abstract: This thesis was divided into two chapters. In the first chapter, the objective was to describe the embryonic development of semi-altricial scarlet ibis (Eudocimus ruber) while identifying critical landmarks for diagnostic and age determination purposes, supporting both artificial incubation and field research on the species. We used eggs collected from a captive population in northern Brazil. A total of 50 embryos were analyzed from day 0 to day 18, focusing on external morphological traits observable through macroscopic examination. Key diagnostic features included the sequential formation of the beak, eyes, neck, feathers, and embryonic annexes. We compared the development of the semi-altricial scarlet ibis with reference descriptions of precocial and altricial species to evaluate the suitability of comparisons between different postnatal growth patterns. The semi-altricial scarlet ibis exhibited heterochronic variations of up to four days in critical developmental landmarks compared to precocial species with similar incubation periods. These findings suggest that developmental timelines. established for precocial species may not be reliable for accurately staging altricial and semi-altricial embryos. Interestingly, the median timing of significant developmental events in the scarlet ibis aligned more closely with those of other altricial species. The daily embryonic milestones described herein provide a valuable reference for scarlet ibis captive breeding programs and contribute to broader conservation efforts for other Threskiornithidae family members or species within the Pelecaniformes order, addressing the limited research on semi-altricial avian development. In the second chapter, we aimed to describe the breeding performance of a captive population of scarlet ibis over a three-year period (2022, 2023, and 2024). We focused on various factors, including the onset and conclusion of the breeding season, couple formation, enclosure density, and laying timing. We conducted statistical analyses to assess the impact of breeder-related factors (such as age and laying timing), egg characteristics (including weight and shape), and incubation parameters (such as egg weight loss) on key zootechnical variables commonly used in poultry production, including laying rate, fertility, and hatchability. Our goal was to establish a breeder profile that could inform mate selection. The onset of the breeding season varied between July and August over the three years, while its conclusion ranged from November to January. Both males and females began forming breeding pairs as early as two years old, with the oldest pairing ages being 20 years for males and 12 years for females. 82,6 ± 4.9% of pairs were monogamous throughout the season. Higher enclosure densities appeared to improve laying rates and encourage earlier laying, while a 1:1 male-to-female ratio facilitated effective pair formation with minimal aggression. Additionally, increased female age correlated with a higher laying rate (p < 0.05). Egg withdrawal stimulated the replacement of eggs in females, resulting in an average of 7.6 ± 2.7 new eggs. The advancement of the laying season significantly influenced initial egg weight (p < 0.01). The median daily weight loss during incubation was 0.74% (tau = 0.5), while the mean weight loss on day 21 was 19 ± 2%. The findings from this study are invaluable for planning efficient breeding programs for the scarlet ibis and potentially for other members of the Threskiornithidae family. 2025-06-03T00:00:00Z https://repositorio.ufra.edu.br/jspui/handle/123456789/2444 Título: Microbioma de búfalas leiteiras: estudo da interação com o bezerro e ambiente ao desenvolvimento de resistência bacteriana. Autor(es): LIMA, Allana Lais Alves Abstract: This thesis was divided into two chapters. In the first chapter, the hypothesis that the buffalo milk microbiome could share taxa with samples from its feces, pasture soil, and even with the saliva of its calf was tested. Additionally, a possible correlation across generations was also studied. For this, milk, feces, and saliva samples were collected in triplicate from first and third-parity animals on a farm in the Marajó Archipelago, Amazon, Pará-Brazil. Pasture soil was also collected. The animals were clinically healthy. The somatic cell count in the milk showed a significant difference when evaluated between heifers and cows. The metabarcoding approach using 16S rRNA demonstrated a significant difference in the phylogenetic and ecological structure among all the matrices studied. Beta-diversity showed clustering between the milk samples of first and third-lactation animals, and similar patterns in feces and saliva samples. The most abundant phyla in the biological samples were Firmicutes, Proteobacteria, and Bacteroidota. When shared, these taxa were found simultaneously in at least two biological matrices, but never in all three matrices at the same time. The phylum Firmicutes was shared between the soil and the milk, and between the feces of cows and heifers. The samples studied presented a matrix-dependent pattern. It was possible to observe the sharing of families in the microbiome of buffalo milk and feces and the saliva of their calves, reinforcing the idea of microbial interaction among them. In the second chapter, the hypothesis was assessed that there would be a correlation between the Gram-negative microbiota in buffalo feces when compared across different lactation numbers, calves, and the environment. To this end, fecal samples were collected from first-lactation (heifer - HF) and fourth-lactation (cow - CW) buffaloes, as well as their respective calves (CFH and CFC) from a farm in the Marajó Archipelago, Pará, Brazil. Soil samples (S) were also collected. The samples were diluted and plated on selective media supplemented with Ceftriaxone (CRO) or Tetracycline (TET) for bacterial isolation. Colonies grown on CRO were subjected to selective pressure using the replication method on plates with Cefepime (CFP) and Imipenem (IMP). Counting, isolation, and identification were performed using MALDI-TOF. In total, 91 bacterial strains were identified: 37 were resistant to TET, 27 to CFP, and 27 to IMP. The strains were identified as *Escherichia coli* (TET [33]; IMP [7]), *Ochrobactrum intermedium* (TET [4]; CFP [19]; IMP [10]), *Achromobacter xyloxidans* (CFP [5]), and *Stenotrophomonas maltophilia* (CFP [3]; IMP [10]). Grouping was observed between the resistance profiles for CFC and CW for the antibiotic IMP; CW, HF, and CFC with group S for the antibiotics TET, IMP, and CFP, respectively. The results highlight the importance of constant monitoring of the bacterial resistance profile in these animals and the surrounding soil, as commensal and environmental bacteria can be indicators of selective pressure and may highlight emerging antimicrobial resistance agents commonly used. 2024-10-18T00:00:00Z