Research Note: The effects of a Lactobacillus helveticus ATCC 15009-derived postbiotic mitigating Salmonella Gallinarum colonization in commercial layer chicks.

This study aimed to assess the effects of a Lactobacillus helveticus ATCC 15009-derived postbiotic in mitigating experimental Salmonella Gallinarum infection. For this purpose, a sample of Lactobacillus sp. was inoculated in 2 different media, each containing different postbiotics (sensitized and nonsensitized). Both inocula had their antagonistic effect over S. Gallinarum tested through the spot-on-the-lawn method. It revealed that the sensitized postbiotic had a higher action potential over Lactobacillus sp. than the nonsensitized one (P < 0.05). Then, 48 day of hatch chicks were divided into 4 groups: A = Lactobacillus sp. (109 CFU/mL) inoculum on the 18th day; B = Lactobacillus sp. (109 CFU/mL) inoculum on the 18th day and postbiotic inoculum on the 19th day; C = postbiotic inoculum on the 19th day; and D = sterile saline inoculum on 18th and 19th days. On the 21st day, all chicks were infected with S. Gallinarum (109 CFU/mL). On the 23rd day, the animals were euthanized by cervical dislocation, and the ceca and liver were aseptically removed. Bacterial count of S. Gallinarum with serial decimal dilution was performed with these organs. It revealed that the prophylactic treatment with the postbiotic that modulates the intestinal microbiota was as efficient as the probiotic administration in reducing S. Gallinarum in the cecum and liver of chicks (P < 0.05). These data point to a new range of alternatives for preventing S. Gallinarum, which might help the poultry industry produce safer food for human consumption.

C-reactive protein concentrations are higher in dogs with stage IV chronic kidney disease treated with intermittent hemodialysis.

In chronic kidney disease dogs, the inflammatory process increases C-reactive protein concentrations. This study aimed to determine C-reactive protein serum concentrations in stage IV chronic kidney disease dogs treated with intermittent hemodialysis. A prospective cohort study was conducted with 23 dogs allocated into three groups: control group (CG, n = 7), intermittent hemodialysis group (IHG, n = 8) and clinical treatment group (CTG, n = 8), both comprised of stage IV chronic kidney disease dogs. One blood sample from CG (initial evaluation) and two samples from IHG and CTG (first- and last-moment) were obtained to determine C-reactive protein concentration, total leukocytes, platelets, erythrocytes, total plasma protein, serum albumin, urea, creatinine, and phosphorus. C-reactive protein was higher in IHG compared to CG in the first- and last-moments (p <0.001) and compared to CTG in the first-moment (p = 0.0406). C-reactive protein presented moderate positive correlation with leukocytes (r = 0.5479; p = 0.01), and moderate negative correlation with albumin (r = - 0.5974; p = 0.006) and red blood cells (r = - 0.5878, p = 0.01). A high correlation coefficient was observed in the tests' evaluation (CI = 0.59-0.78; r = 0.70; P<0.0001). In conclusion, both assays used in this study to measure C-reactive protein have provided safe and reliable quantification of the results. Additionally, despite IHG dogs presented an active inflammatory profile, intermittent hemodialysis has proven to be beneficial, leading to a clinical improvement in life quality of patients, and thus being recommended for stage IV CKD dogs when performed by trained professionals.

Inflammatory response of miniature horses subjected to open and half-closed orchiectomy techniques.

BACKGROUND: This study aimed to evaluate the inflammatory response of miniature horses subjected to open and half-closed orchiectomy by physical examination, blood cell count, peritoneal fluid evaluation, total plasma protein, fibrinogen, and serum amyloid A (SAA) concentrations. METHODS: Thirteen male healthy miniature horses were divided into two groups, according to the surgical approach: half-closed technique (HCT) and open technique (OT). The HCT group was subjected to ligation of the spermatic cord followed by its sharp incision, and closure of the vaginal tunic, and the OT group was only submitted to cord ligation. Prior to, and at 1, 2, 3 and 5 days after the surgery, a general and specific physical examination, blood cell counts, total plasma protein, peritoneal fluid evaluation, fibrinogen, and SAA concentrations were performed. RESULTS: Higher postoperative perilesional oedema, rectal temperature, and fibrinogen were observed in the HCT group. Groups did not differ as to SAA concentrations. The evaluated local and systemic inflammatory profile demonstrated that, as expected, surgery resulted in inflammation in both groups. CONCLUSIONS: The group subjected to the HCT showed a more intense and lasting inflammatory response. However, despite the different postoperative inflammatory profiles, both groups presented a favourable outcome and recovery.

Extracellular vesicles of follicular fluid from heat-stressed cows modify the gene expression of in vitro-matured oocytes.

The effect of heat stress (HS) on cattle reproduction is deleterious with respect to ovarian follicular development and oocyte quality. The objective of this study was to investigate the effect of follicular fluid extracellular vesicles (EVs) obtained from cows maintained in thermoneutral (TN) or HS conditions on in vitro oocyte maturation. Nonlactating cows were estrous synchronized. Immediately after ovulation day (D1), the cows were randomly assigned to TN or HS environments. Follicular fluid from all follicles from each treatment was pooled, and EVs were obtained. Pools of 20 cumulus oocyte-complexes (COCs), were allocated to the following treatments: Control (n = 4 COC pools): matured in base medium; TN (n = 4 COC pools): matured in base medium supplemented with TN EV suspension; and HS (n = 4 COC pools): matured in base medium that was supplemented with the HS EV suspension. All treatments were conducted at 38.5 °C for 24 h in a humid atmosphere with 5% CO2. After maturation, the COCs were evaluated for meiotic progression, DNA integrity and oocyte quality-related gene expression. When the experimental groups were compared with the control group, a treatment effect was not observed for meiotic progression and DNA integrity. In the cumulus cells of TN group, there was relatively lesser expression of the IGFBP4 gene. In the oocytes of the TN as compared with the HS group, the IGFBP2, BMP15, GDF9, CDCA8, HAS2, RPL15, STAT3 and PFKP genes were expressed to a lesser extent. The findings indicated that oocytes matured in the presence of EVs from the follicular fluid of cows collected when there were TN conditions, however, there was a lesser expression of genes related to oocyte quality.

Thermoregulatory responses of Holstein cows exposed to experimentally induced heat stress.

Heat stress (HS) adversely influences productivity and welfare of dairy cattle. We hypothesized that the thermoregulatory mechanisms vary depending on the exposure time to HS, with a cumulative effect on the adaptive responses and thermal strain of the cow. To identify the effect of HS on adaptive thermoregulatory mechanisms and predictors of caloric balance, Holstein cows were housed in climate chambers and randomly distributed into thermoneutral (TN; n=12) or HS (n=12) treatments for 16 days. Vaginal temperature (VT), rectal temperature (Tre), respiratory rate (RR), heart rate (HR), and dry matter intake (DMI) were measured. The temperature and humidity under TN were 25.9±0.2°C and 73.0±0.8%, respectively, and under HS were 36.3±0.3°C and 60.9±0.9%, respectively. The RR of the HS cows increased immediately after exposure to heat and was higher (76.02±1.70bpm, p<0.001) than in the TN (39.70±0.71bpm). An increase in Tre (39.87±0.07°C in the HS vs. 38.56±0.03°C in the TN, p<0.001) and in VT (39.82±0.10°C in the HS vs. 38.26±0.03°C in the TN, p<0.001) followed the increase in RR. A decrease (p<0.05) in HR occurred in the HS (62.13±0.99bpm) compared with the TN (66.23±0.79bpm); however, the magnitude of the differences was not the same over time. The DMI was lower in HS cows from the third day (8.27±0.33kgd-1 in the HS vs. 14.03±0.29kgd-1 in the TN, p<0.001), and the reduction of DMI was strongly affected (r=-0.65) by changes in the temperature humidity index. The effect of environmental variables from the previous day on physiological parameters and DMI was more important than the immediate effect, and ambient temperature represented the most determinant factor for heat exchange. The difference in the responses to acute and chronic exposure to HS suggests an adaptive response. Thus, intense thermal stress strongly influence thermoregulatory mechanisms and the acclimation process depend critically on heat exposure time.

Transferência de embriões em éguas receptoras anovulatórias / Embryo transfer in anovulatory recipient mares / Transferencia de embriones en yeguas receptoras anovulatorias

Resumo: Este artigo discute os principais aspectos do uso de protocolos hormonais baseados na aplicação de estrógeno seguido de progestágenos em receptoras anovulatórias o acíclicas, seja em anestro ou transição nos protocolos de transferência de embriões. A maioria das éguas apresentam comportamento poliéstrico estacional, com o que manifestam estro e ciclos ovulatórios nos períodos de maior luminosidade diária. O ciclo reprodutivo anual das éguas é caracterizado pela presença de quatro fases definidas pela dinâmica folicular: de anestro, de transição de primavera, ovulatória e de transição de outono. Durante as fases de transição e anestro, a incidência das ovulações diminui ou é nula, ou que dificulta a sincronização das ovulações entre doadoras e receptoras durante a preparação para a transferência de embriões. Alguns estudos mostram que as receptoras anovulatórias/acíclicas mantidas com protocolos com base em esteroides apresentam mudanças uterinas similares às que acontecem nas éguas gestantes. Contudo, não há pesquisas suficientes que permitam esclarecer o melhor protocolo de esteroides, no que se refere à dose, tempos de tratamento e vias de administração.

Abstract: This article discusses the main aspects of using hormonal protocols based on the application of estrogen followed by progestogen in anovulatory or acyclic recipients, either in anestrous or transition in embryo transfer protocols. Most mares demonstrate seasonally polyestrous behavior, by which they manifest estrus and ovulatory cycles during periods of higher daily luminosity. The annual reproductive cycle of mares is characterized by the presence of four phases defined by follicular dynamics: anestrous, spring transition, ovulatory, and autumn transition. During the phases of transition and anestrous, the incidence of ovulations decreases or is zero, making it difficult to synchronize ovulations between donors and recipients in preparation for embryo transfer. Some studies have shown that anovulatory/acyclic recipient mares managed with steroid-based protocols have similar uterine changes to those observed in pregnant mares. However, there is no sufficient research to allow to clarify the best steroid protocol with respect to dose, treatment times, and routes of administration.

Resumen: Este artículo discute los principales aspectos del uso de protocolos hormonales basados en la aplicación de estrógeno seguido de progestágeno en receptoras anovulatorias o acíclicas, sea en anestro o transición en los protocolos de transferencia de embriones. La mayoría de las yeguas presentan comportamiento poliéstrico estacional, con lo que manifiestan estro y ciclos ovulatorios en los periodos de mayor luminosidad diaria. El ciclo reproductivo anual de las yeguas es caracterizado por la presencia de cuatro fases definidas por la dinámica folicular: de anestro, de transición de primavera, ovulatoria y de transición de otoño. Durante las fases de transición y anestro, la incidencia de las ovulaciones disminuye o es nula, lo que dificulta la sincronización de las ovulaciones entre donadoras y receptoras durante la preparación para la transferencia de embriones. Algunos estudios han mostrado que las receptoras anovulatorias/acíclicas mantenidas con protocolos con base en esteroides presentan cambios uterinos similares a los que pasan en las yeguas gestantes. Sin embargo, no hay investigaciones suficientes que permitan aclarar el mejor protocolo de esteroides, con respecto a dosis, tiempos de tratamiento y vías de administración.