A comparative study of the bacterial diversity and composition of nursery piglets' oral fluid, feces, and housing environment.

The oral cavity is the portal of entry for many microorganisms that affect swine, and the swine oral fluid has been used as a specimen for the diagnosis of several infectious diseases. The oral microbiota has been shown to play important roles in humans, such as protection against non-indigenous bacteria. In swine, studies that have investigated the microbial composition of the oral cavity of pigs are scarce. This study aimed to characterize the oral fluid microbiota of weaned pigs from five commercial farms in Brazil and compare it to their respective fecal and environmental microbiotas. Bacterial compositions were determined by 16S rRNA gene sequencing and analyzed in R Studio. Oral fluid samples were significantly less diverse (alpha diversity) than pen floor and fecal samples (P < 0.01). Alpha diversity changed among farms in oral fluid and pen floor samples, but no differences were observed in fecal samples. Permutational ANOVA revealed that beta diversity was significantly different among sample types (P = 0.001) and farms (P = 0.001), with separation of sample types (feces, pen floor, and oral fluid) on the principal coordinates analysis. Most counts obtained from oral fluid samples were classified as Firmicutes (80.4%) and Proteobacteria (7.7%). The genera Streptococcus, members of the Pasteurellaceae family, and Veillonella were differentially abundant in oral fluid samples when compared to fecal samples, in which Streptococcus was identified as a core genus that was strongly correlated (SparCC) with other taxa. Firmicutes and Bacteroidota were the most relatively abundant phyla identified in fecal and pen floor samples, and Prevotella_9 was the most classified genus. No differentially abundant taxa were identified when comparing fecal samples and pen floor samples. We concluded that under the conditions of our study, the oral fluid microbiota of weaned piglets is different (beta diversity) and less diverse (alpha diversity) than the fecal and environmental microbiotas. Several differentially abundant taxa were identified in the oral fluid samples, and some have been described as important colonizers of the oral cavity in human microbiome studies. Further understanding of the relationship between the oral fluid microbiota and swine is necessary and would create opportunities for the development of innovative solutions that target the microbiota to improve swine health and production.

Deconstruction of a multi-strain Bacillus-based probiotic used for poultry: an in vitro assessment of its individual components against C. perfringens.

OBJECTIVE: Probiotics have been used in poultry production to improve the performance and health of chickens raised without antibiotics. The combination of different probiotic strains has been used with the hope of conferring multiple benefits to the host. However, the inclusion of several strains does not necessarily boost benefits. There is a lack of studies that compare the efficacy of multi-strain probiotics to their individual components. In this study, the effects of a Bacillus-based probiotic product mix containing B. coagulans, B. licheniformis, B. pumilus, and B. subtilis against Clostridium perfringens were tested in vitro using a co-culture method. The individual strains and different combinations of the strains used in the product were also tested against C. perfringens. RESULTS: The probiotic product mix tested in this study did not show effects against C. perfringens (P = 0.499). When tested individually, the strain of B. subtilis was the most efficient strain to decrease C. perfringens concentrations (P ≤ 0.01), and the addition of other Bacillus species strains significantly decreased its efficacy against C. perfringens. We concluded that the probiotic mix of Bacillus strains used in this study (B. coagulans, B. licheniformis, B. pumilus and B subtilis) was not effective in decreasing C. perfringens concentrations in vitro. However, when deconstructing the probiotic, the strain of B. subtilis alone or combined with the strain of B. licheniformis were effective against C. perfringens. This suggests that the anticlostridial properties of the particular strains of Bacillus used in this study were negatively affected when combined with other Bacillus spp. strains.

Effect of Hardwood Dust and Ammonia Gas on the Respiratory Integrity of Broiler Chickens.

Dust and ammonia gas (NH3) are two of the most abundant pollutants suspended in the air of poultry houses. Chronic inhalation of poultry dust and NH3 causes damage to the airways and reduces performance in broilers. Poultry dust is a mixture of organic and inorganic matter from feed, bedding material, manure, feathers, skin debris, and microorganisms. Thus, the composition and concentration of poultry dust vary among farms. This study proposes a model to assess the individual effect of a defined fraction of poultry dust derived from bedding material (wood dust) and its effects, alone or combined with NH3, on the performance and respiratory integrity of broilers. Ninety-six, 1-day-old broilers were randomly divided into groups of 24 and placed into four controlled environment chambers to continuously receive one of four treatments: 1) negative control; 2) exposure to airborne red oak wood dust at a concentration of 7.5 × 106 particles/m3 (particulate matter5.0); 3) exposure to 50 parts per million (ppm) of NH3; and 4) exposure to airborne red oak wood dust and 50 ppm of NH3. On day 43, all birds were weighed and euthanized. Performance data were recorded. Tissue samples were collected from six birds per treatment. Histologic evaluations of the nasal turbinates, trachea, and lungs were conducted. Histologic lesion scores (0 to 3) were assigned, and tracheal mucosal thickness was measured. No significant differences among treatments were found in body weight (P = 0.066), tracheal mucosal thickness (P = 0.593), or tracheal lesion score (P = 0.07). The average nasal turbinate lesion scores were higher in the wood and wood + ammonia treatments compared with the control (P = 0.015). The lung lesion scores were higher (P = 0.004) in all treatment groups compared with the control. In conclusion, chronic exposure to red oak wood dust, alone or in combination with NH3, induced important inflammatory damage to portions of the respiratory system of broilers; however, no significant effects on performance were observed.

Efecto del polvo de madera dura y el gas amoníaco en la integridad respiratoria de pollos de engorde. El polvo y el gas amoníaco (NH3) son dos de los contaminantes más abundantes suspendidos en el aire de las casetas avícolas. La inhalación crónica de polvo en casetas avícolas y de NH3 provoca daños en las vías respiratorias y reduce el rendimiento de los pollos de engorde. El polvo de aves de corral es una mezcla de materia orgánica e inorgánica procedente del alimento, material de cama, estiércol, plumas, restos de piel y microorganismos. Por lo tanto, la composición y concentración del polvo de las aves de corral varía entre granjas. Este estudio propone un modelo para evaluar el efecto individual de una fracción definida de polvo avícola derivado del material de cama (polvo de madera) y sus efectos, solos o combinados con NH3, sobre el rendimiento y la integridad respiratoria de los pollos de engorde. Noventa y seis pollos de engorde de un día de edad se distribuyeron aleatoriamente en grupos de 24 y se colocaron en cuatro cámaras de ambiente controlado para recibir continuamente uno de los cuatro tratamientos: 1) control negativo; 2) exposición a polvo de madera de roble rojo en el aire a una concentración de 7.5 × 106 partículas/m3 (material particulado5.0); 3) exposición a 50 partes por millón (ppm) de NH3; y 4) exposición a polvo de madera de roble rojo en el aire y 50 ppm de NH3. Durante el día 43, todas las aves fueron pesadas y se les practicó la eutanasia. Se registraron los datos de rendimiento. Se recogieron muestras de tejido de seis aves por tratamiento. Se realizaron evaluaciones histológicas de los cornetes nasales, la tráquea y los pulmones. Se asignaron puntuaciones de lesiones histológicas (0 a 3) y se midió el espesor de la mucosa traqueal. No se encontraron diferencias significativas entre los tratamientos en el peso corporal (P = 0.066), el grosor de la mucosa traqueal (P = 0.593) o la puntuación de la lesión traqueal (P = 0.07). Las puntuaciones medias de las lesiones de los cornetes nasales fueron más altas en los tratamientos con madera y madera + amoníaco en comparación con el control (P = 0.015). Las puntuaciones de lesiones pulmonares fueron más altas (P = 0.004) en todos los grupos de tratamiento en comparación con el control. En conclusión, la exposición crónica al polvo de madera de roble rojo, solo o en combinación con NH3, indujo un daño inflamatorio importante en partes del sistema respiratorio de los pollos de engorde; sin embargo, no se observaron efectos significativos en el rendimiento.

Inclusion of high-flavonoid corn in the diet of broiler chickens as a potential approach for the control of necrotic enteritis.

Avian necrotic enteritis (NE) is an infectious disease that impacts poultry worldwide causing economic losses. Discontinued use of antimicrobial growth promoters has been associated with high incidence of the disease, which has led to a necessity for finding new therapeutic alternatives. Flavonoids are polyphenolic compounds that have been studied for their health-promoting properties in animals and humans. This study presents a flavonoid-rich corn (PennHFD), as a potential alternative for ameliorating NE in broiler chickens. The effect of a diet formulated with PennHFD was compared to a diet based on commercially available corn in chickens subjected to a controlled challenge of NE based on a co-infection of Eimeria maxima and Clostridium perfringens. Birds fed on the PennHFD-based diet had lower incidence of intestinal lesions (P = 0.048), higher body weight gain (P < 0.01), lower feed conversion ratio (P < 0.01), and lower mortality rates (P = 0.023) compared to the control diet. Therefore, we concluded that the inclusion of the high-flavonoid PennHFD reduces the severity of an experimental challenge of NE in broiler chickens.