Unsteady flow dynamics resonated via the natural acoustic mode of a duct with tandem side-branches in a unique half-wavelength arrangement were experimentally investigated. The wavelength ...corresponded to the first natural acoustic mode of a duct–branch system, which can be easily triggered in a low-speed flow and result in a strong flow–acoustic resonance. Considering the remote arrangement, albeit one involving close flow interactions between the faraway side-branches, a dual particle image velocimetry (PIV) setup was established to simultaneously capture the upstream and downstream side-branches. In addition, an advanced phase-locking technique based on a field-programmable gate array (FPGA) control system and real-time acoustic waveform recognition approach was established to increase the phase-determination accuracy. Using this dual-FPGA-PIV system, the high-frequency acoustically resonated flow dynamics could be accurately divided into multiphase-dependent flow snapshots within an extremely small acoustic period, while ensuring the high spatial resolution of the flow fields. Preliminary pressure measurements and acoustic modal analysis were conducted to confirm the occurrence of flow–acoustic resonance inside such ducts with half-wavelength arranged side-branches. Subsequently, time-averaged flow measurements were obtained using a planar-PIV system to investigate the flow dynamic variations. It was noted that the acoustic modulation effect outweighed the Reynolds number effect and dominated the intensive flow fluctuations in the duct–branch system. Thereafter, phase-dependent flow measurements were obtained using the dual-FPGA-PIV setup to illustrate the spatiotemporal evolutions of the coherent flow structures associated with the resonance in the duct–branch system. Due to the symmetric nature of the resonated first acoustic mode, synchronous in-phase movement of the streamwise shear-layer vortices occurred between the faraway upstream and downstream side-branches.
Graphical abstract
Preventative effects of
Lactobacillus fermentum
and
Bacillus coagulans
against
Clostridium perfringens
infection in broilers have been well-demonstrated. The present study was conducted to ...investigate the modulation of these two probiotics on intestinal immunity and microbiota of
C. perfringens
-challenged birds. The 336 one-day-old broilers were assigned to four groups with six replicates in each group. Birds in the control were unchallenged and fed a basal diet, and birds in the three challenged groups were dietary supplemented with nothing (Cp group), 1 × 10
9
CFU/kg of
L. fermentum
(Lf_Cp group), or 1 × 10
10
CFU/kg of
B. coagulans
(Bc_Cp group). Challenge was performed from days 14 to 20, and samples were collected on days 21 and 28. Challenge upregulated interleukin (IL)-1β and transforming growth factor (TGF)-β4 mRNA expression in jejunum on day 21, which was downregulated by
B. coagulans
and
L. fermentum
, respectively (
P
< 0.05). Both probiotic groups upregulated jejunal IL-1β, interferon (IFN)-γ, IL-17, and TGF-β4 on day 28 as well as IFN-γ on day 21 (
P
< 0.05). The Bc_Cp group increased CD3
+
T cell counts in the jejunal crypt on day 21 (
P
< 0.05). Challenge decreased the ileal ACE index on day 21 and cecal microbial richness on day 28, which were increased by probiotic treatments, and ileal bacterial richness decreased in the Bc_Cp group on day 28 (
P
< 0.05). Only ileal microbiota on day 21 was distinctly affected with an R-value at 0.3116 by ANOSIM analysis (
P
< 0.05). Compared with the control, ileal
Firmicutes
increased on day 21, and ileal
Bacteroidetes
and cecal
Proteobacteria
decreased on day 28 in challenged groups (
P
< 0.05). Challenge increased
Romboutsia
spp. in the ileum as well as unclassified f_
Lachnospiraceae
and
Ruminococcus_torques
group in the cecum, and decreased
Lactobacillus
spp. in the ileum on day 21, which were all conversely modulated by
L. fermentum
(
P
< 0.05). Challenge increased amino acid metabolism of ileal microbiota and membrane transport of cecal microbiota, and decreased amino acid metabolism of cecal microbiota on day 21, which were conversely regulated by both probiotics (
P
< 0.05). In conclusion,
L. fermentum
and
B. coagulans
attenuated the intestinal inflammation and microbial dysbiosis soon after
C. perfringens
challenge.
Necrotic enteritis (NE) is an important enteric inflammatory disease of poultry, and the effects of vitamin A (VitA) on NE birds are largely unknown. The present study was conducted to investigate ...the effects of VitA on the immune responses and VitA metabolism of NE broilers as well as the underlying mechanisms. Using a 2 × 2 factorial arrangement, 336 1-day-old Ross 308 broiler chicks were randomly assigned to 4 groups with 7 replicates. Broilers in the control (Ctrl) group were fed a basal diet without extra VitA supplementation. Broilers in the VitA group were fed a basal diet supplemented with 12,000 IU/kg of VitA. Birds in NE and VitA + NE groups were fed corresponding diets and, in addition, co-infected with
spp. and
on days 14 to 20. Samples of the blood, jejunum, spleen and liver were obtained on day 28 for analysis, and meanwhile, lesion scores were also recorded. The results showed that NE challenge increased lesion score in the jejunum and decreased serum glucose, total glyceride, calcium, phosphorus and uric acid levels (
< 0.05). VitA supplementation reduced the levels of serum phosphorus, uric acid and alkaline phosphatase in NE-challenged birds and increased serum low-density lipoprotein content and the activity of aspartate aminotransferase and creatine kinase (
< 0.05). Compared with the Ctrl group, the VitA and NE groups had higher mRNA expression of interferon-γ in the jejunum (
< 0.05). NE challenge up-regulated mRNA expression of interleukin (
)-13, transforming growth factor-β4, aldehyde dehydrogenase (
)-2 and
in the jejunum, while VitA supplementation increased jejunal
mRNA expression and hepatic VitA content, but down-regulated splenic
mRNA expression (
< 0.05). The VitA + NE group had higher serum prostaglandin E
levels and the Ctrl group had higher splenic
mRNA expression than that of the other three groups (
< 0.05). NE challenge up-regulated jejunal retinoic acid receptor (
)-β and retinoid X receptor (
)-α as well as splenic
and
mRNA expression (
< 0.05). VitA supplementation up-regulated jejunal
expression but down-regulated mRNA expression of
,
, signal transducers and activators of transcription (
) 5 and
in the spleen (
< 0.05). Moreover, compared with the Ctrl group, the VitA and NE groups had down-regulated mRNA expression of jejunal and splenic Janus kinase (
) 1 (
< 0.05). In conclusion, NE challenge induced jejunal injury and expression of Th2 and Treg cell-related cytokines and enhanced
and
mRNA expression, mainly in the jejunum of broilers. VitA supplementation did not alleviate jejunal injury or Th2 cell-related cytokine expression; however, it improved hepatic VitA deposition and inhibited the expression of
,
and the JAK/STAT signaling pathway in the spleen of broilers. In short, the present study suggested the modulatory effects of vitamin A on the immune responses and vitamin A metabolism in broiler chickens challenged with necrotic enteritis.
Necrotic enteritis (NE) impairs poultry production and causes great economic loss. The nutritional regulation of diets has the potential to alleviate NE. The present study was conducted to ...investigate the effects of dietary supplementation with vitamin A (VA) on the antioxidant and intestinal barrier function of broilers co-infected with coccidia and C. perfringens (CCP). In a 2 × 2 factorial arrangement, 336 one-day-old Ross 308 broilers were divided into four treatments with two levels of VA (0 or 12,000 IU/kg) and challenged with or without CCP. The animal trial lasted for 42 days. The results showed that dietary supplemental VA improved body weight gain (BWG) and the feed intake (FI), and the FI was negatively affected by CCP. Additionally, the levels of catalase (CAT) in the serum, total superoxide dismutase (T-SOD), and CAT in the jejunum and glutathione peroxidase (GSH-Px) in the liver decreased with the CCP challenge (p < 0.05). The mRNA levels of SOD, CAT, GSH-Px1, and GSH-Px3 in the liver and jejunum were upregulated by the CCP challenge (p < 0.05). In addition, the level of serum diamine oxidase (DAO), and the mRNA level of ZO-1 were also upregulated with the CCP challenge. Dietary supplementation with VA contributed to the intestinal villi height and the mRNA level of Mucin-2 in the jejunum (p < 0.05). Additionally, dietary VA had the ability to alleviate the upregulation of SOD in the liver and SOD, CAT, GSH-Px1, GSH-Px3, ZO-1, and claudin-1 in the jejunum with the CCP challenge (p < 0.05). However, the mRNA level of GSH-Px3 and the levels of SOD in the liver and jejunum were downregulated with the VA supplementation in the diet. In conclusion, dietary VA improved the growth performance and the intestinal barrier function; nonetheless, it failed to alleviate the negative effects of CCP on the antioxidant function in broilers.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
The purpose of this study was to determine the efficacy of tannic acid on the antioxidative function, immunity, and intestinal barrier of broilers co-infected with coccidia and
(CCP). A total of 294 ...1-day-old arbor acres(AA) broilers were divided into three groups: control group (CON), CCP co-infected group (CCP), and 1000 mg/kg TA + CCP co-infected group (CTA). This trial lasted for 28 days. The results showed that the CCP group decreased the activity of glutathione peroxidase (GSH-Px), total superoxide dismutase (T-SOD), catalase (CAT), and total antioxidant capacity (T-AOC) levels and increased the contents of hydrogen peroxide (H
O
) and malondialdehyde (MDA) in the jejunum (
< 0.05). The mRNA levels of GSH-Px3 and CAT in the liver and jejunum, and the mRNA levels of GSH-Px3, SOD, HO-1, and NAD(P)H quinone oxidoreductase I (NQO1) in the liver were down-regulated by CCP challenge (
< 0.05). In addition, the Keap1 and Nrf2 mRNA levels in the liver and jejunum, jejunal glutathione S-transferase (GST), and heme-oxygenase-1 (HO-1) were upregulated in the CCP group compared with CON (
< 0.05). The mRNA levels of interleukin 8 (IL-8), IL-1β, inducible nitric oxide synthase (iNOS), and interferon γ (IFN-γ) in the jejunum were elevated, and jejunal mRNA levels of IL-10, zonula occludens protein1 (ZO-1), claudin-1, claudin-2, and occludin were decreased in the CCP treatment (
< 0.05). Dietary supplementation with 1000 mg/kg TA increased the activity of GSH-Px, T-SOD, CAT, and T-AOC and decreased the contents of H
O
and MDA in the jejunum (
< 0.05). Compared with the CCP group, TA decreased the mRNA level of Keap1 and Nrf2 in the liver and jejunum, increased the GSH-Px3, SOD, and CAT mRNA in the liver, and alleviated the rise of IL-8, IL-1β, iNOS, and IFN-γ and decrease in IL-10, occludin gene expression in the jejunum (
< 0.05). In conclusion, the addition of 1000 mg/kg TA to the diet improved the jejunal barrier, mitigated the jejunal inflammation, and increased the antioxidant capacity of the liver and jejunum through the activation of the transcription factor Nrf2 downstream of the Nrf2-Keap1 pathway in broilers with NE condition.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
This study was conducted to investigate effects of dietary
and
supplementation on the intestinal stem cell proliferation, immunity, and ileal microbiota of broiler chickens challenged by coccidia and
.... A total of 336 one-day-old Ross 308 chickens were randomly assigned into four groups. Chickens in the control (CTR) group were fed basal diet, and chickens in the three challenged groups were fed basal diets supplemented with nothing (CCP group), 1.0 × 10
CFU/kg
(LF_CCP group), and 1.0 × 10
CFU/kg
(LP_CCP group), respectively. All challenged birds were infected with coccildia on day 9 and
during days 13-18. The serum and intestinal samples were collected on days 13 and 19. The results showed that
significantly increased jejunal gene expression of
(one of the intestinal stem cell marker genes) on day 13. Additionally,
significantly up-regulated mRNA levels of
and
and tended to increase
mRNA expression in jejunum on day 19. In the cecal tonsil, both
and
decreased mRNA expression of
on day 13, and
down-regulated
,
, and
gene expressions on day 19. Ileal microbiological analysis showed that coccidial infection increased the
-
,
, and
abundance and decreased
richness on day 13, which were reversed by
intervention. Moreover,
increased ileal
richness on day 19. In conclusion,
alleviated the impairment of intestinal stem cell proliferation and immunity in coccidia- and
-challenged birds via modulating JAK/STAT signaling and reshaping intestinal microflora.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Necrotic enteritis (NE) is a great threat to the intestinal health of broilers, resulting in decreased growth performance and significant economic losses.
(
) and
(
) exert beneficial effects on ...intestinal health. The aim of the present study was to investigate the effects of dietary
and
on the intestinal health and growth performance of broilers challenged with coccidia and
(CCP). The animal trial was carried out using 336 broilers (Ross 308) for 35 days with a completely randomized design. The broilers were divided into 4 groups based on treatment as follows: the control (CTR) group was fed the basal diet and without CCP challenge and the CCP group was fed the basal diet and with CCP challenge. The broilers in the CCP+
and CCP+
groups were challenged by CCP, and meanwhile,
(1 × 10
CFU/g) and
(1 × 10
CFU/g) were supplemented into the basal diets, respectively. The results showed that the growth performance and the intestinal morphology were negatively affected by the CCP challenge. In addition, the number of coccidia in the intestinal digesta and the relative abundance of
in the cecal digesta were increased. Besides, the mRNA level of
in the jejunum was downregulated, and the transcript level of
was upregulated by the CCP challenge. Dietary
and
failed to improve the growth performance of broilers with the CCP challenge. However, they were beneficial for intestinal barrier function. In addition, dietary
was able to alleviate the downregulation of
β mRNA level in the spleen with CCP challenge and decreased the lesion scores compared with the CCP group. Furthermore, dietary
alleviated the upregulation of the
mRNA level in the jejunum with CCP challenge and reduced the number of coccidia in the ileal digesta. In conclusion, dietary
and
failed to mitigate the negative effects of CCP infection on growth performance; however, they were able to improve the intestinal health of broilers challenged with CCP by strengthening the intestinal barrier and alleviating inflammation.
Porcine epidemic diarrhea virus (PEDV) has become a challenging problem in pig industry all over the world, causing significant profit losses. Tannins and organic zinc have been shown to exert ...protective effects on the intestinal dysfunction caused by endotoxins. However, there is little information on tannic acid-chelated zinc (TAZ) supplementation in the diet of newborn piglets. This study was conducted to determine the effects of TAZ on the intestinal function of piglets infected with PEDV. Thirty-two 7-day-old piglets were randomly allocated to 1 of 4 treatments in a 2 × 2 factorial design consisting of 2 diets (0 or 50 mg/kg BW TAZ) and challenge (saline or PEDV). On day 9 of the trial, 8 pigs per treatment received either sterile saline or PEDV solution at 10
6
TCID
50
(50% tissue culture infectious dose) per pig. Pigs infected with PEDV had greater diarrhea rate and lower average daily gain (ADG) (
P
< 0.05). PEDV infection decreased plasma D-xylose concentration, most antioxidative enzyme activities in plasma and intestine, as well as the small intestinal villus height (
P
< 0.05). Plasma diamine oxidase and blood parameters were also affected by PEDV infection. Dietary supplementation with TAZ could ameliorate the PEDV-induced changes in all measured variables (
P
< 0.05). Moreover, TAZ decreased the concentration of malondialdehyde in plasma, duodenum, jejunum, and colon (
P
< 0.05). Collectively, our results indicated that dietary TAZ could alleviate PEDV induced damage on intestinal mucosa and antioxidative capacity, and improve the absorptive function and growth in piglets. Therefore, our novel findings also suggest that TAZ, as a new feed additive for neonatal and weaning piglets, has the potential to be an alternative to ZnO.
We conducted this study to compare the effects of lactic acid bacteria complex (L. casei, L. rhamnosus, L. lactis, L. plantarum, S. thermophilus, and B. longum) and Enterococcus faecium DSM 7134 in ...weanling pigs. A total of 120 weanling pigs (24-day-old) were used in a 5-week feeding trial. Pigs were allotted into three dietary treatments: CON, basal diet; LA, CON + 0.1% lactic acid bacteria complex; EF, and CON + 0.1% E. faecium DSM 7134. From days 0 to 14, days 15 to 35, and the overall period, average daily gain was higher (P < .05) in EF than that in CON. Higher gain:feed ratio was also observed in EF compared with CON during the overall period. The apparent total tract digestibility of dry matter, nitrogen, and gross energy was greater (P < .05) in LA and EF compared with CON on days 14 and 35. Faecal Lactobacillus counts were increased (P < .05) and faecal pH was decreased in LA and EF compared with CON on days 14 and 35. Results of the current study indicated that E.faecium DSM 7134 has better effects on growth performance than lactic acid bacteria complex in weanling pigs.
A total of 480 one-day-old AA broiler chicks were randomly allocated to one of four treatments in a 2 × 2 factorial to investigate the effects of tannic acid (TA) on growth performance, relative ...organ weight, antioxidant capacity, and intestinal health in broilers dietary exposed to aflatoxin B
1
(AFB
1
). Treatments were as follows: (1) CON, control diet; (2) TA, CON + 250 mg/kg TA; (3) AFB
1
, CON + 500 μg/kg AFB
1
; and (4) TA+AFB
1
, CON + 250 mg/kg TA + 500 μg/kg AFB
1
. There were 10 replicate pens with 12 broilers per replicate. Dietary AFB
1
challenge increased the feed conversion ratio during days 1 to 21 (
P
< 0.05). The TA in the diet did not show significant effects on the growth performance of broilers during the whole experiment period (
P
> 0.05). The liver and kidney relative weight was increased in the AF challenge groups compared with the CON (
P
< 0.05). The addition of TA could alleviate the relative weight increase of liver and kidney caused by AFB
1
(
P
< 0.05). Broilers fed the AFB
1
diets had lower activity of glutathione peroxidase, catalase, total superoxide dismutase, S-transferase, and total antioxidant capacity in plasma, liver and jejunum, and greater malondialdehyde content (
P
< 0.05). Dietary supplemented with 250 mg/kg TA increased the activities of antioxidative enzymes, and decreased malondialdehyde content (
P
< 0.05). In addition, AFB
1
significantly reduced the villus height and crypt depth ratio in the ileum on day 42 (
P
< 0.05). In conclusion, supplementation with 250 mg/kg TA could partially protect the antioxidant capacity and prevent the enlargement of liver in broilers dietary challenged with 500 μg/kg AFB
1
.
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