Banca de DEFESA: ALISSON LEANDRO ANSOLIN

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : ALISSON LEANDRO ANSOLIN
DATE: 19/07/2023
TIME: 13:30
LOCAL: Web Conferência - Microsoft Teams - BANCA FECHADA.
TITLE:

IMPACT OF ORIGIN OF BIRTH, AGE AND HOUSING SYSTEM OF BOAR ON BACTERIAL CONTAMINATION AND PRODUCTIVITY OF SEMEN DOSES

KEY WORDS:

semen bacteriology, swine semen, preputial fluid, preputial washing.

PAGES: 45
BIG AREA: Ciências Agrárias
AREA: Medicina Veterinária
SUMMARY:

Understanding the impact of contamination of swine ejaculates and productivity related to extrinsic factors is essential for the development of control measures. This can result in improving the quality of semen doses and minimizing the use of antibiotics. The aim of this study was to evaluate the effect of origin, housing location, age, and preputial washing on bacterial contamination and production of boar ejaculate doses. In experiment 1, 24 boars (186.6 ± 7.6 d) from a commercial genetic lineage were used in a 2 x 2 factorial design: two multiplier origins of the breeders, origin A (n=12) and origin B (n=12), and two housing sheds of the gene dissemination unit (UDG), shed 1 and shed 2. The boars remained in quarantine (30 d) and were then transferred to the main sheds (1 and 2) of the UDG. Shed 1 had air conditioning based on negative air pressure, slatted floors in the boar stalls, and compact floors in the corridors, while shed 2 had positive air pressure, fully slatted floors, and auxiliary fans located in the boar rows. During the boars' stay in the UDG sheds, 5 swab and preputial fluid collections were made, as well as pure ejaculate and diluted doses. Boars were kept on a weekly ejaculate collection regimen at the UDG for 196 d, and the same person managed them during the entire period. Sperm analyses (motility and morphology) in CASA system (AndroVision®, Minitub, Germany) and quantification of colony-forming units (CFUs) were performed. Boars from origin B housed in shed 2 had lower CFU counts (P<0.05) than boars from origin A, regardless of the shed (1.4 ± 0.2 vs 1.9 ± 0.1 Log10, respectively). In addition, a negative correlation (r= -0.27) was observed between age of boar and contamination of raw semen sample (P<0.01; considering age variation during the study). Furthermore, in terms of ejaculate quality and production of insemination doses, boars from origin A housed in shed 1 had a higher rate of discard due to poor morphology (P<0.0001), lower total motility of pure ejaculate (P<0.01), lower concentration/ejaculation (P<0.05), and as a result, a lower number of doses produced (P<0.01). Finally, origin A boars had a greater chance (4.4 times) of requiring medical intervention (antibiotics and anti-inflammatory) compared to origin B. In experiment 2, ejaculates (n=201) from 144 boars of the same genetic lineage were randomly divided into 2 groups: preputial washing (G1, n=81 ejaculates) and without preputial washing (G2, n=120 ejaculates). The boars were housed in the same shed and subjected to semen collection by the same person. Preputial washing consisted of infusing 120 ml of 0.9% NaCl solution divided between the preputial canal and diverticulum, and the washing was performed immediately before each collection. For all boars, fresh ejaculate and diluted doses were obtained, and for some boars (n=47), the pre-spermatic portion was collected independently of the group. Regarding CFUs, a difference (P<0.0001) was observed when comparing pure ejaculate between the groups with and without preputial washing (1.72 ± 0.08 vs 2.47 ± 0.14 Log10, respectively). No difference (P>0.05) was observed between the motility data of the groups with and without preputial washing. When comparing the level of contamination between the pre-spermatic portion and the rest of the pure ejaculate, the pre-spermatic portion had a higher CFU when compared to the rest of the ejaculate portion (2.85 ± 0.16 vs 2.02 ± 0.07, respectively; P<0.001). In conclusion, birth origin and housing shed and age of the boars had an effect on productivity of pure ejaculate contamination, insemination doses, and medical interventions. Preputial washing and the portion of the ejaculate influence the level of bacterial contamination in pure ejaculate.

COMMITTEE MEMBERS:
Externo à Instituição - RICARDO ZANELLA - UPF
Externa à Instituição - MONIKE QUIRINO DOS SANTOS - IFC
Presidente - 2648941 - IVAN BIANCHI