Effects of dietary triiodothyronine or dopamine on small intestinal oxygen consumption in chicks.

This study aimed to investigate the effects of triiodothyronine (T3)- or dopamine (Dp)-supplemented diets on oxygen consumption by Na+, K+-ATPase activity in broiler chicks. Five groups, each with twenty-four 6-day-old chicks, randomly received one of the five dietary treatments: (1) Basal diet (commercial broiler rations with 23.0% crude protein and 3,133 kcal metabolizable energy/kg) or CON, (2) basal diet plus 0.7 µmol Dp/kg diet or Dp0.7, (3) basal diet plus 2.4 µmol Dp/kg diet or Dp2.4, (4) basal diet plus 1.9 µmol T3/kg diet or T1.9, and (5) basal diet plus 3.8 µmol T3/kg diet or T3.8 from 6 to 14 days of age. There were four replicates per treatment and 120 birds in total. At 14 days of age, three chicks from each replicate of each treatment were pooled into a flock and fed commercial broiler diets until 7 weeks of age. Compared to CON group, birds fed with T3-supplemented diets had lower thyroid, abdominal fat pad, gizzard and pancreas weight, and heavier heart weight adjusted for fasted body weight. Chicks with T1.9 had lower ileal densities at 14 day old compared with those in Dp groups or CON. Chicks with T3.8 exhibited greater duodenal and jejunal O2 consumptions as well as ouabain-sensitive O2 consumptions of jejunum and small intestine (duodenum, jejunum, and ileum) by 46.5%, 58.3%, 40.6%, and 26.4% increases, than those in CON. Partial correlation analysis revealed that the weight and length of the small intestine were negatively correlated with body weight gain. Oxygen consumption in the various small intestinal segments was negatively correlated with their respective densities (mg/mm2). In conclusion, a greater oxygen requirement for maintaining ouabain-sensitive respiration (Na+-K+-ATPase) in the intestine limits energy availability to support gastrointestinal tract growth and, thereby, may result in lower body weight gain.

The Potential of Peroxidases Extracted from the Spent Mushroom (Flammulina velutipes) Substrate Significantly Degrade Mycotoxin Deoxynivalenol.

Little is known about the degradability of mycotoxin deoxynivalenol (DON) by the spent mushroom substrate (SMS)-derived manganese peroxidase (MnP) and lignin peroxidase (LiP) and its potential. The present study investigated the growth inhibition of Fusarium graminearum KR1 and the degradation of DON by MnP and LiP extracted from SMS. The results from the 7-day treatment period showed that mycelium inhibition of F. graminearum KR1 by MnP and LiP were 23.7% and 74.7%, respectively. Deoxynivalenol production in the mycelium of F. graminearum KR1 was undetectable after treatment with 50 U/mL of MnP or LiP for 7 days. N-acetyl-D-glucosamine (GlcNAc) content and chitinase activity both increased in the hyphae of F. graminearum KR1 after treatment with MnP and LiP for 1, 3, and 6 h, respectively. At 12 h, only the LiP-treated group had higher chitinase activity and GlcNAc content than those of the control group (p < 0.05). However, more than 60% of DON degradabilities (0.5 mg/kg, 1 h) were observed under various pH values (2.5, 4.5, and 6.5) in both MnP (50 U/g) and LiP (50 U/g) groups, while DON degradability at 1 mg/kg was 85.5% after 50 U/g of LiP treatment for 7 h in simulated pig gastrointestinal tracts. Similarly, DON degradability at 5 mg/kg was 67.1% after LiP treatment for 4.5 h in simulated poultry gastrointestinal tracts. The present study demonstrated that SMS-extracted peroxidases, particularly LiP, could effectively degrade DON and inhibit the mycelium growth of F. graminearum KR1.

Mycotoxin Fumonisin B1 Interferes Sphingolipid Metabolisms and Neural Tube Closure during Early Embryogenesis in Brown Tsaiya Ducks.

Fumonisin B1 (FB1) is among the most common contaminants produced by Fusarium spp. fungus from corns and animal feeds. Although FB1 has been known to cause physical or functional defects of embryos in humans and several animal species such as Syrian hamsters, rabbits, and rodents, little is known about the precise toxicity to the embryos and the underlying mechanisms have not been fully addressed. The present study aimed to investigate its developmental toxicity and potential mechanisms of action on sphingolipid metabolism in Brown Tsaiya Ducks (BTDs) embryos. We examined the effect of various FB1 dosages (0, 10, 20 and 40 µg/embryo) on BTD embryogenesis 72 h post-incubation. The sphingomyelin content of duck embryos decreased (p < 0.05) in the highest FB1-treated group (40 µg). Failure of neural tube closure was observed in treated embryos and the expression levels of a neurulation-related gene, sonic hedgehog (Shh) was abnormally decreased. The sphingolipid metabolism-related genes including N-acylsphingosine amidohydrolase 1 (ASAH1), and ceramide synthase 6 (CERS6) expressions were altered in the treated embryos compared to those in the control embryos. Apparently, FB1 have interfered sphingolipid metabolisms by inhibiting the functions of ceramide synthase and folate transporters. In conclusion, FB1-caused developmental retardation and abnormalities, such as neural tube defects in Brown Tsaiya Duck embryos, as well as are partly mediated by the disruption of sphingolipid metabolisms.

Differential Effects of Green Tea Powders on the Protection of Brown Tsaiya and Kaiya Ducklings against Trichothecene T-2 Toxin Toxicity.

A 3-week feeding trial in a 3 × 2 × 2 factorial design was conducted with three concentrations (0, 0.5, and 5 mg/kg) of T-2 toxin (T-2) and two levels (0% and 0.5%) of green tea powder (GTP) supplements used in the diets of female brown Tsaiya ducklings (BTDs) and Kaiya ducklings (KDs), respectively. Breed had a significant effect on the growth performances and the relative weights of organs and carcass. In general, the growth performances of KDs were better than BTDs. The relative weights of organs and carcass of BTDs were typically heavier than those of KDs; however, the breast of KDs was heavier than those of BTDs. Both ducklings received 5 mg/kg of T-2 blended in the diet showed lower feed intake and body weight gain (BWG) in the second and the third week. The diet containing 5 mg/kg of T-2 and 0.5% GTP improved the BWG compared to those fed the diet supplemented with 5 mg/kg of T-2 without GTP in BTDs. Ducklings fed the diet containing 5 mg/kg of T-2 induced hypocalcemia and hypomagnesemia, as well as decreased concentrations of creatine phosphokinase and alkaline phosphatase. The concentrations of blood urea nitrogen (BUN) and glutamate oxaloacetate transaminase (GOT) were increased in KDs and BTDs fed the diet containing 5 mg/kg of T-2 without GTP, respectively. However, duckling diets containing 5 mg/kg of T-2 with 0.5% GTP lowered concentrations of BUN and GOT in the blood plasma of KDs and BTDs, respectively. The diet containing 5 mg/kg of T-2 increased the relative kidney weight but decreased the relative breast weight of ducklings. Enlarged gizzards and reduced relative leg weights were observed in BTDs fed the diets containing 5 mg/kg of T-2. In summary, BTDs are more sensitive than KDs in responding to T-2 toxicity and GTP detoxification. Green tea powder has detoxification ability and could potentially mitigate T-2 toxicity on BWG, BUN, and GOT in ducklings.

Ultrastructural Characterization of Porcine Growing and In Vitro Matured Oocytes.

This study aimed to investigate ultrastructural changes of growing porcine oocytes and in vitro maturated oocytes. Light microscopy was used to characterize and localize the primordial, primary, secondary, and tertiary follicles. During oocyte growth and maturation, the morphology of mitochondria was roundish or ovoid in shape depending on the differentiation state, whereas their mean diameters oscillated between 0.5 and 0.7 µm, respectively, from primary and secondary follicles. Hooded mitochondria were found in the growing oocytes of the tertiary follicles. In addition to the pleomorphism of mitochondria, changes in the appearance of lipid droplets were also observed, along with the alignment of a single layer of cortical granules beneath the oolemma. In conclusion, our study is apparently the first report to portray morphological alterations of mitochondria that possess the hooded structure during the growth phase of porcine oocytes. The spatiotemporal and intrinsic changes during oogenesis/folliculogenesis are phenomena at the ultrastructural or subcellular level of porcine oocytes, highlighting an in-depth understanding of oocyte biology and impetus for future studies on practical mitochondrion replacement therapies for oocytes.

Enzyme Degradation Reagents Effectively Remove Mycotoxins Deoxynivalenol and Zearalenone from Pig and Poultry Artificial Digestive Juices.

Mycotoxin removers include enzymes and adsorbents that may be used in animal feeds to eliminate the toxic effects of mycotoxins. This study aimed to determine the removability of two different types of mycotoxin removers, adsorbents and enzyme degradation reagents (EDRs), in the simulated gastrointestinal conditions of pigs and poultry. Seven commercial mycotoxin removers, including five EDRs and two adsorbents, were tested in vitro. In this study, the supplemented dosages of mycotoxin removers used in pig and poultry feeds were the commercial recommendation ranging from 0.05% to 0.2%. For pigs, the in vitro gastric and small intestinal simulations were performed by immersing the mycotoxin-tainted feed in artificial gastric juice (AGJ) at pH 2.5 for 5 h or in artificial intestinal juice (AIJ) at pH 6.5 for 2 h to mimick in vivo conditions. For poultry, mycotoxin-tainted feeds were immersed in AGJ for 2 h at pH 4.5 and 0.5 h at pH of 2.5, respectively, to simulate crop/glandular stomach and gizzard conditions; the small intestinal simulation was in AIJ for 2 h at pH 6.5. For the pig, EDRs and adsorbents had deoxynivalenol (DON) removability (1 mg/kg) of 56% to 100% and 15% to 19%, respectively. Under the concentration of 0.5 mg/kg, the zearalenone (ZEN) removability by EDRs and adsorbents was 65% to 100% and 0% to 36%, respectively. For the simulation in poultry, the removability of DON by EDRs and adsorbents (5 mg/kg) was 56% to 79% and 1% to 36%, respectively; for the concentration of 0.5 mg/kg, the removability of ZEN by EDRs and adsorbents was 38% to 69% and 7% to 9%, respectively. These results suggest that EDRs are more effective in reducing DON and ZEN contamination compared to the adsorbent methods in the simulated gastrointestinal tracts of pig and poultry. The recoveries of DON and ZEN of pig in vitro gastrointestinal simulations were higher than 86.4% and 84.7%, respectively, with 88.8% and 85.9%, respectively, in poultry. These results demonstrated the stability and accuracy of our mycotoxin extraction process and in vitro simulation efficiency.

Developmental Toxicity of Mycotoxin Fumonisin B1 in Animal Embryogenesis: An Overview.

A teratogenic agent or teratogen can disturb the development of an embryo or a fetus. Fumonisin B1 (FB1), produced by Fusarium verticillioides and F. proliferatum, is among the most commonly seen mycotoxins and contaminants from stale maize and other farm products. It may cause physical or functional defects in embryos or fetuses, if the pregnant animal is exposed to mycotoxin FB1. Due to its high similarity in chemical structure with lipid sphinganine (Sa) and sphingosine (So), the primary component of sphingolipids, FB1 plays a role in competitively inhibiting Sa and So, which are key enzymes in de novo ceramide synthase in the sphingolipid biosynthetic pathway. Therefore, it causes growth retardation and developmental abnormalities to the embryos of hamsters, rats, mice, and chickens. Moreover, maternal FB1 toxicity can be passed onto the embryo or fetus, leading to mortality. FB1 also disrupts folate metabolism via the high-affinity folate transporter that can then result in folate insufficiency. The deficiencies are closely linked to incidences of neural tube defects (NTDs) in mice or humans. The purpose of this review is to understand the toxicity and mechanisms of mycotoxin FB1 on the development of embryos or fetuses.

Characterizing early embryonic development of Brown Tsaiya Ducks (Anas platyrhynchos) in comparison with Taiwan Country Chicken (Gallus gallus domestics).

Avian embryos are among the most convenient and the primary representatives for the study of classical embryology. It is well-known that the hatching time of duck embryos is approximately one week longer than that of chicken embryos. However, the key features associated with the slower embryonic development in ducks have not been adequately described. This study aimed to characterize the pattern and the speed of early embryogenesis in Brown Tsaiya Ducks (BTD) compared with those in Taiwan Country Chicken (TCC) by using growth parameters including embryonic crown-tail length (ECTL), primitive streak formation, somitogenesis, and other development-related parameters, during the first 72 h of incubation. Three hundred and sixty eggs from BTD and TCC, respectively, were incubated at 37.2°C, and were then dissected hourly to evaluate their developmental stages. We found that morphological changes of TCC embryos shared a major similarity with that of the Hamburger and Hamilton staging system during early chick embryogenesis. The initial primitive streak in TCC emerged between 6 and 7 h post-incubation, but its emergence was delayed until 10 to 13 h post-incubation in BTD. Similarly, the limb primordia (wing and limb buds) were observed at 51 h post-incubation in TCC embryos compared to 64 h post-incubation in BTD embryos. The allantois first appeared around 65 to 68 h in TCC embryos, but it was not observed in BTD embryos. At the 72 h post-incubation, 40 somites were clearly formed in TCC embryos while only 32 somites in BTD embryos. Overall, the BTD embryos developed approximately 16 h slower than the chicken embryo during the first 72 h of development. To our best knowledge, this is the first study to describe two distinct developmental time courses between TCC and BTD, which would facilitate future embryogenesis-related studies of the two important avian species in Taiwan.

Effects of short light regimes and lower dietary protein content on the reproductive performance of White Roman geese in an environment-controlled house.

The objective of this study is to investigate the effects of short light regimes and lower dietary protein content on the reproductive performance of White Roman geese in an environment- controlled house. Thirty-two ganders and 80 geese during the third laying period were allotted into 16 pens, randomly assigned into a split-plot design with two different lighting regimes: (1) short light regimes (SL) with 6.5h of light and 17.5h of dark (6.5L:17.5D), and (2) long light regimes (LL) with 19L:5D during the 6-wk prelaying period, followed by two different levels of protein diets (Low CP: 15% vs. High CP: 18%) for the laying period. The results showed that birds treated with the SL light regime had a heavier body weight compared to those treated with LL at the arrival of the peak period of egg production (6.19 vs. 5.87kg, P<0.05). Geese under LL had a longer laying period than those under SL treatment (277 vs. 175day, P<0.05), while the geese under SL treatment had a higher laying intensity (15.4% vs. 12.6%, P<0.05), fertility and hatchability than those under LL treatment. Our results suggest that the White Roman geese treated with 6-wk short light regime during the prelaying period and on the low CP diet during the laying period found conditions sufficient to sustain their regular reproduction performance, which would benefit geese farmers in the perspectives of energy saving and prolonged laying period.

Nonylphenol reduces sperm viability and fertility of mature male breeders in Brown Tsaiya ducks (Anas platyrhynchos).

The aim of this study was to investigate the effect of nonylphenol (NP), a widely used surfactant, on the reproductive performance of male Brown Tsaiya ducks (Anas platyrhynchos) (MBBTDs). Mature MBBTDs (n=100) were treated with NP by daily gavaging of 0, 1 (NP1), 10 (NP10) and 250 (NP250) mg/kg-BW/d for 14 wk. Semen quality, fertilization rate and specific factors in blood plasma were measured. Weights of organs were also measured at 14 wk after NP administration. Ducks from each treatment (n=4) were continually treated with NP thereafter for 12 mo to observe changes of tissue ultrastructure by microscopic examination. The results showed that ducks treated with amounts of NP of greater than 1mg NP/kg BW/d (NP1) for 14 wk had decreased sperm viability (32.3%) compared to those in the control group (74.1%, P<0.05). The fertilization rate of ducks treated with 250mg NP/kg-BW/d (NP250) for 14 wk was reduced (21.0%) compared to the control group (74.5%, P<0.05). Plasma aminotransferase (AST) and alanine aminotransferase (ALT) activities were also greater in NP250 group at the 14th wk post-treatment. Plasma testosterone concentrations were increased by NP1 treatment at the 14th wk post-treatment. Administration at dosage 250mg NP/kg-BW/d for 12 mo resulted in reduced sperm counts (P<0.05) and histopathological changes, such as dilated seminiferous tubules (P<0.05) and degenerated spermatocytes (P<0.05). These findings strongly suggest that NP adversely affects the reproductive performance of MBBTDs.