Density Of Villi Research Articles

Effects of Different Feeding Frequencies on Broiler Chickens’ Growth Performance and Intestinal Villus Development

This experiment was conducted to determine the effects of feeding frequency on growth performance and development of small intestine in broiler chickens from 1 to 14 days of age. Forty Aber acres broiler chicks at 1 day old were randomly assigned to 4 treatments as follows - T1: feeding once daily (100 % diet at 6:30), T2: feeding twice daily (50 % diet at 6:30 and 18:30), T3: feeding 4 times per day (25 % diet at 6:30, 11:30, 16:30 and 21:30) and T4: feeding 6 times per day (16.67 % diet at 6:30, 9:30, 12:30, 15:30, 18:30 and 21:30). Chickens were fed with commercial broiler rations for 14 days. Growth performance parameters including BW, BW gain, FI and FCR were determined. Changes in intestinal villus morphology were examined by hematoxylin and eosin (H&E) dye staining. Results showed that chickens fed 4 and 6 times per day had lower (p < 0.05) BW, BW gain and FI when compared with chickens fed once daily, from 1 to 7 days of age. However, at 14 days of age, there were no significant differences in all parameters of growth performance. There were no changes in gross anatomy of the small intestine. Fixed feeding 4 and 6 times per day resulted in the villus height of the jejunum and ileum being higher (p < 0.05) than when feeding once a day. Feeding 6 times per day resulted in the highest villus density in jejunum among feed regimes. The results suggested that both once and multiple daily feedings were suitable approaches to achieve optimum growth performance for broiler chickens from 1 to 14 days of age. Fixed feeding 6 times per day being the most beneficial for improving intestinal villus development. HIGHLIGHTS Feeding frequency is one of feed restriction method in broilers management From 1 to 7 days of age feeding fed 4 and 6 times per day show lower growth performance than feeding once daily, but not for 14 days of age Fixed feeding 4 and 6 times per day present the villus height at jejunum and ileum higher than feeding once daily Fixed feeding 6 times per day is the most effective solution for enhancing intestinal villus development Here, the experiment demonstrates for the first time that the compensatory growth effects by frequently feeding is at least mediated through adaptation of villus morphology in the small intestine along with improved feed consumption GRAPHICAL ABSTRACT

Inclusion of Soybean Hulls (Glycine max) and Pupunha Peach Palm (Bactris gasipaes) Nanofibers in the Diet of Growing Rabbits: Effects on Zootechnical Performance and Intestinal Health.

This study evaluated the inclusion of nanofibers from soybean hulls and pupunha peach palm heart sheaths in the diet of growing rabbits. Twenty-four New Zealand White rabbits (male and female) were allocated in three experimental groups: control, fed a basal diet; Nanosoy, fed a diet containing 7% soybean-hull nanofibers; and Nanopupunha, fed a diet containing 7% pupunha palm heart-sheath nanofibers. The Nanosoy-group rabbits showed poorer final weight, daily feed intake, and daily weight gain than those in other groups. In the duodenum, villus height, total mucosal thickness, and villus width were higher in rabbits that received nanofiber-supplemented diets than in the controls. Higher villus density and wall thickness were observed in Nanopupunha-fed rabbits than in the controls. In the jejunum, although the crypt depth was higher in Nanosoy-fed rabbits, the villus height:crypt depth ratio was higher in the Nanopupunha-fed group. Nanosoy-fed animals exhibited increased count Enterobacteriaceae populations. Rabbits in both nanofiber-fed groups exhibited higher lactic-acid bacterial counts than those in the control-diet group. Therefore, although the inclusion of 7% Nanopupunha in the diet of rabbits did not alter the performance, it improved intestinal health and increased the lactic-acid bacterial count in the cecum of growing rabbits.

Effects of polystyrene nanoplastics on oxidative stress, histopathology and intestinal microbiota in largemouth bass (Micropterus salmoides)

Nanoplastics (NPs) can be taken up by aquatic organism and profoundly impact the growth and fitness of aquatic animals in the ecosystem. Currently, the influence of NPs in commercial fish is still poorly documented, especially in carnivorous freshwater fish. To investigate the effects of NPs in water on growth performance, oxidative stress, histopathology, and intestinal microbiota of Micropterus salmoides, juvenile fish (initial weight 14.56 ± 0.09 g) were exposed to 10 and 100 μg/L polystyrene NPs (100 nm) for seven days and nineteen days. The results showed that no significant difference was found in growth among all the experimental groups. NPs caused obvious histological changes in gills (e.g., hyperplasia, curvature, fragmentation, capillary dilatation), livers (e.g., hypertrophy, infiltration, lipid droplet, vacuolization) and intestines (e.g., increase/decrease of gut villus density and length, decrease of goblet cells). The SOD and CAT activities in livers of the high NPs (100 μg/L) group were significantly higher than that of the control group after nineteen-day exposure (P < 0.05). The MDA level of the high NPs (100 μg/L) group was significantly higher than that of the control group after seven-day exposure (P < 0.05), but no significant difference was found in MDA among all the experimental groups after nineteen-day exposure. M. salmoides might adapt to the environment containing NPs through the changes in the intestine microbiota affecting or promoting the growth of the different bacterial genera. This study provides novel insight beyond the current understanding of the potential toxicological effects and NP contamination in M. salmoides.

Risk factors for small intestinal adenocarcinomas that are common in the proximal small intestine.

The frequency of primary small intestinal adenocarcinoma is increasing but is still low. Its frequency is approximately 3% of that of colorectal adenocarcinoma. Considering that the small intestine occupies 90% of the surface area of the gastrointestinal tract, small intestinal adenocarcinoma is very rare. The main site of small intestinal adenocarcinoma is the proximal small intestine. Based on this characteristic, dietary animal proteins/lipids and bile concentrations are implicated and reported to be involved in carcinogenesis. Since most nutrients are absorbed in the proximal small intestine, the effect of absorbable intestinal content is a suitable explanation for why small intestinal adenocarcinoma is more common in the proximal small intestine. The proportion of aerobic bacteria is high in the proximal small intestine, but the absolute number of bacteria is low. In addition, the length and density of villi are greater in the proximal small intestine. However, the involvement of villi is considered to be low because the number of small intestinal adenocarcinomas is much smaller than that of colorectal adenocarcinomas. On the other hand, the reason for the low incidence of small intestinal adenocarcinoma in the distal small intestine may be that immune organs reside there. Genetic and disease factors increase the likelihood of small intestinal adenocarcinoma. In carcinogenesis experiments in which the positions of the small and large intestines were exchanged, tumors still occurred in the large intestinal mucosa more often. In other words, the influence of the intestinal contents is small, and there is a large difference in epithelial properties between the small intestine and the large intestine. In conclusion, small intestinal adenocarcinoma is rare compared to large intestinal adenocarcinoma due to the nature of the epithelium. It is reasonable to assume that diet is a trigger for small intestinal adenocarcinoma.

Growth indices, intestinal histomorphology, and blood profile of rabbits fed probiotics- and prebiotics-supplemented diets.

In a 12-week feeding trial, 32 rabbits (Chinchilla × New Zealand White; 56 days old; 691 ± 1 g body weight) were used to investigate the effect of pro- and prebiotics as growth enhancer on the growth performance, intestinal mucosal development, hematological and serum biochemical responses of rabbits. The dietary Biotronic® prebiotics and Biovet®-YC probiotics were added at 400 mg/kg and 50 mg/kg, respectively. The rabbits were housed individually and randomly assigned to four dietary treatments (n = 8/group; 50:50 bucks to does) including a control diet (diet 1), diet 2 (control + Biotronic® prebiotics), diet 3 (control + Biovet®-YC probiotics) and diet 4 (control + symbiotics [Biotronic® prebiotics and Biovet®-YC probiotics]). Body weight (BW), average daily gain (ADG), dry matter intake (DMI), and feed conversion ratio (FCR) were monitored. Five rabbits per treatment were used for organ assessment and intestinal histomorphology after feeding trial. Blood samples were collected for hematological and serum biochemical analysis. Results showed that supplementation of Biotronic® prebiotics and symbiotics in rabbit diet significantly (P < 0.05) increased final BW and ADG compared to Biovet®-YC probiotic and control diets. Kidney, lung, esophagus, gastro-intestinal tract, small and large intestines were significantly (P < 0.05) influenced by dietary treatments. Ileal mucosal assessment revealed that villus height (VH), villus width, villus density, crypt depth (CD), and VH:CD ratio of rabbits fed Biotronic® prebiotic and symbiotic diets were similar and significantly (P < 0.05) higher than those rabbits fed control and Biovet®-YC probiotic diets. Packed cell volume of rabbits fed symbiotic and control diets was significantly (P < 0.05) higher than those fed Biotronic® prebiotic and Biovet®-YC probiotic diets. This study suggests that Biotronic® prebiotics and its combination with Biovet®-YC probiotics are good alternative growth promoting feed additives in rabbit nutrition. They improved performance, intestinal development and blood profiles and aid feed digestion, nutrient absorption and utilization in rabbits.

Microscopic structure of the rectum of the domestic duck

As a rule, researchers pay less attention to the features of the large intestine than to the small intestine. The purpose of the study was to determine the features of the microscopic structure of the rectum of ducks during the first year of the postnatal period of ontogenesis. For histological examinations, the material was selected from Ukrainian white-breasted ducks of 9 age groups: 1-, 3-, 7-, 14-, 21-day-old, 1-, 2-, 6-month-old and 1-year-old. Morphometric parameters of microstructures were set on cross sections of the midgut. The general change pattern in the morphometric parameters of the microstructures of the rectum of ducks was their increase, which was asynchronous and uneven. There was observed an active intestinal morphogenesis continued, as evidenced by the process of formation of villi and crypts in the group of 1-3-day-old ducks. The most intensive morphometric parameters of the rectum changed in the first month of the postnatal period of ontogenesis, during which – in the first week. In the first week, first and second month of life of ducks, the wall thickness of the rectum increased by 93.1, respectively; 199.5 and 20.4 %, the thickness of the mucous membrane – 81.0; 167.1 and 19.5 %, the thickness of the muscular membrane – by 126.1; 285.3 and 22.7 %, the height of the villi – by 113.2; 208.7 and 7.2 %, the width of the villi – by 84.7; 70.9 and 12.5 %, their surface area – by 293.8; 427.6 and 20.6 %, the depth of the crypt – by 85.1; 49.9 and 52.3 %, muscle plate thickness – by 254.0; 750.8 and 15.0 %. The most stable indicators of the rectum during the first year of the postnatal period of ontogenesis were the density of villi and crypts, the number of which after 7 days of age had no significant difference compared to that of a younger age. The indicates of adult birds morphometric parameters of the rectum of ducks corresponded at different ages: in 1-year-old – the thickness of the serous membrane and the density of villi; at 6 months – the diameter of the intestine, the surface area of the villi; at 2 months of age – the thickness of the wall and its mucous membrane, the width of the villi, the depth of the crypt; at 1 month – the thickness of the muscular membrane and plate, the height of the villi, the epithelium of the villi and crypt; at 3 days of age – the density of crypts; at 1 day of age – the width of the crypt.

PSIII-24 Effect of two sources of encapsulated sodium butyrate on broilers performance

Abstract The study was conducted to elucidate effects of feed supplementation with two sources of encapsulated sodium butyrate (ESB, ~30% sodium butyrate encapsulated with vegetable fat) respect to a control diet, on broilers performance. A total of 960 Ross308 one-day-old chicks were randomly distributed into 3 treatments with 16 replicates and 20 birds per replicate: CON (control diet), AD (CON + 2.19kg/tn of ESB from supplier 1) and GUSTOR (CON + 2.19kg/tn of ESB from supplier 2). Feed and water were offered ad libitum. Performance was recorded at 0, 21 and 42d at pen level, and the results presented were corrected by mortality; gut morphology from jejunum at 42 days was also recorded. Data were analyzed with one-way ANOVA using the GLM procedure of SAS. Regarding body weight, some numerical differences were observed between control and groups with ESB at 21d (777g, 786g, and 784g, for CON, AD and GUSTOR, respectively) and at 41d (2719g, 2727g and 2734g, for CON, AD and GUSTOR, respectively). From 0-21d, 22-42d and 0-42d average daily feed intake (ADFI, g/d) was significantly affected by treatment (0-42d: 101b, 100b, 98a, for CON, AD and GUSTOR, respectively, P = 0.045). Feed conversion ratio (FCR) followed the same trend and was significantly improved by GUSTOR at 21 (0-21d: 1.52b, 1.52b and 1.48a for CON, AD and GUSTOR, respectively, P = 0.002) and at 42 days (0-42d: 1.59b, 1.58b and 1.56a for CON, AD and GUSTOR, respectively, P &amp;lt; 0.001). No differences were found in villus height and density, crypt depth and density, number of goblet cells and mucus layer in jejunum at 42d. As expected, the results showed no differences on gut morphology due to a totally encapsulated active principle without activity in the small intestine. Even though both ESB were similar, birds supplemented with ESB-GUSTOR were more efficient than birds supplemented with ESB-AD.

Effect of arginine or glutamine supplementation and milk feeding allowance on small intestine development in calves

The development of the small intestine (SI) is important for the health and growth of neonatal calves. This study evaluated the effect of arginine (Arg) and glutamine (Gln) supplementation and 2 levels of milk allowance on the histomorphological development of the SI in preweaning calves. Sixty mixed-sex Friesian × Jersey calves (3-5 d of age) were offered reconstituted whole milk (125 g/L, 26% fat, 26% protein) at either high (20% of arrival body weight/d; HM) or low (10% of arrival body weight/d; LM) milk allowance without (Ctrl) or with supplementary Arg or Gln (at 1% of milk dry matter) in a 2 × 3 factorial design (n = 10/treatment). After 35 d on the diets, all calves were slaughtered to collect tissues for examination of SI development. Calves in the HM group had higher milk intake, total weight gain, and average daily gain compared with LM calves, but no effect of AA supplementation nor an interaction between milk allowance and AA supplementation was observed. For the duodenum, we observed an AA by milk allowance interaction for villus height and width, and goblet cell number per villus (HM-Arg > HM-Gln > HM-Ctrl), and villus height to crypt depth ratio (HM-Arg > HM-Gln = HM-Ctrl), but no effect of AA supplementation in the LM group. Goblet cell numbers per 100 µm of SI were greater in Arg-supplemented calves than in unsupplemented controls, with Gln-supplemented calves intermediate to but not different from the other groups. Epithelium thickness was greater in LM than in HM calves. Villus density, crypt depth, and muscle thickness did not differ between groups. For the jejunum, there was an AA by milk allowance interaction for villus height, villus surface area, and villus height to crypt depth ratio (HM-Arg = HM-Gln > HM-Ctrl), with no effect of AA supplementation in the LM groups. Amino acid supplementation affected goblet cell number per villus (HM-Gln > HM-Ctrl calves, HM-Arg intermediate), and both LM-Arg and LM-Gln calves had greater numbers than LM-Ctrl calves. Villus width, crypt depth, and muscle thickness were greater in HM than LM calves but there was no effect of AA supplementation. Villus density, goblet cell number per 100 µm of SI, and epithelium thickness were unaffected by AA supplementation and milk allowance. Milk allowance and AA supplementation had no effect on SI morphology in the ileum. Increasing milk allowance improved villus height, width, and surface area but only in Arg- or Gln-supplemented calves, not in control calves. The observed changes in development may be important for intestinal functionality, integrity, and barrier function in preweaning calves, potentially through increased cell growth and proliferation or reduced levels of cellular atrophy.

Особливості мікроскопічної будови сліпих кишок качок

According to the literature review, there have been paid less attention to the peculiarities of the large intestine of domestic birds than to the small intestine. The cecum is studied mainly in terms of their microbiome and assessment of the state of the immune system through the study of the structure and cell composition of lymphoid formations. Researchers note the role of the cecum in productivity, maintaining the health and well-being of animals. The aim of the paper was to study the features of the microscopic structure of the caecum of ducks in the first year of the postnatal ontogenesis period. Determination of morphometric parameters of microstructures was performed on histological specimens from a cross section of the middle caecum of ducks 1-, 3-, 7-, 14- and 21-days old, 1-, 2- and 6-month old and 1-year-old. Active morphogenesis of intestinal microstructures was observed in 1-3-day-old ducks, as evidenced by the process of villi and crypt formation. The older ducks, their main feature of the microscopic structure of the cecum anatomy was the increase with age of their morphometric parameters, which was uneven and asynchronous. However, the density of villi and crypts did not change with the age of the bird. The indexes of adult birds morphometric parameters of the ducks cecum corresponded at different ages: the diameter of the intestine, the thickness of the serous membrane, the density of villi, the depth of the crypt – In 1 year; villi width – In 6-month; the thickness of the intestinal wall, its mucous membrane, the density of villi, their surface area, the height of the epithelium of the crypt – In 1 month; the height of the villi and their epithelium, the thickness of the muscular membrane and muscle plate - in 21 days; width and density of crypts – at 3 days sold. The most intensive increase in morphometric parameters of the caecal microstructures occurred in the first month of the postnatal period of ontogenesis, during which they changed most rapidly in the first week.

Stereological analysis of terminal villi, intervillous space and fibrinoid of adolescent placentas and birth weight of newborns.

Aim To determine stereological structural parameters of the parenchymal part of the placenta, placental weight and volume of adolescent pregnant women and their correlation with newborns' birth weight. Methods This prospective study was conducted on a total of 60 human placentas of term pregnancy, divided into two groups according to the age of pregnant women. Experimental group consisted of 30 placentas of pregnant women aged 13-19 years. Control group consisted of 30 placentas of pregnant women aged 20-35 years. Stereological analysis was performed. Results Volumetric density of terminal villi of adolescent placentas was significantly higher than the one of control group (p <0.0001). The volumetric density of fibrinoid of adolescent placentas was significantly lower than of the control group (p <0.0001). Total volume of terminal villi of adolescent placentas was significantly higher than of the control group (p<0.0001). The total volume of fibrinoid of adolescent placentas was significantly lower than of the control group (p<0.0001). Newborns of adolescent pregnancies had in average lower birth weight of 439.01 g compared to the newborns of the control group (p <0.00001). Conclusion Adolescent pregnancy affects placental structure, weight and volume. Newborns of adolescent pregnancy have optimal body weight.

Effects of dietary beta-glucans, glucomannans and mannan oligosaccharides or chlorohydroxyquinoline on the performance, diarrhea, hematological parameters, organ weight and intestinal health of weanling pigs

This study proposes to evaluate the addition a prebiotic product based on beta-glucans (β-glucans), glucomannans, and mannan oligosaccharides (MOS), replacing an antimicrobial growth promoters in diets for newly weaned piglets, on their performance, occurrence of diarrhea (OD), hematological parameters, organ morphometry, pH of the digestive content, and intestinal epithelium morphology. The experiment involved 120 piglets weaned at 21 days of age, with an initial weight of 6.35 ± 0.10 kg, which were allotted to five treatments in a completely randomized block design with six replicates and four piglets per experimental unit. The following treatments were: 0 – basal diet; 1000, 2000, or 3000 mg/kg of a prebiotic; and ANT – basal diet with 120 mg/kg chlorohydroxyquinoline. The inclusion of prebiotic levels in the diet caused a worsening (P < 0.05) in feed conversion (FC). Hematological analysis revealed that prebiotic levels in the diet provided a quadratic effect (P < 0.05) in eosinophil count. The antimicrobial treatment provided a better FC (P < 0.05). Prebiotic levels elicited a quadratic response from villus density (VD) in the duodenum and, in the jejunum, VD decreased linearly (P < 0.05). The ANT treatment led to a lower VD (P < 0.05), in duodenum, compared with treatment 3000 mg/kg. In the jejunum, VD increased (P < 0.05) in ANT when compared with 1000 and 3000 mg/kg of prebiotic. Based on the present results, 3000 mg/kg of a prebiotic are not a viable alternative to performance-enhancing antimicrobials in the diet of piglets.

Expression of glucose transporters and morphometry in the intestine of Japanese quails after hatch.

The intestinal physiology and mechanisms involved in nutrient transport are not well established in quails (Coturnix coturnix japonica). The present study assessed the growth performance, morphological development, duodenal density and the expression of Sglt1 and Glut2 of female Japanese quails from 1 to 49days of age. The three small intestine segments were sampled weekly from 1 to 49days of age to evaluate villus height, crypt depth and villus: crypt ratio, and goblet cell counts. Scanning electronic microscopy was used to determine duodenal villus density, and real-time polymerase chain reaction (qPCR) was used to study the sodium/glucose cotransporter-1 Sglt1 and glucose transporter Glut2 in the jejunum. Villus height and crypt depth in the duodenum, jejunum and ileum increased with age until 42 and 49days of age (P < 0.001), and regression analysis evidenced a quadratic effect (P < 0.0001), indicating increasing values to a maximum and then a decrease afterwards. Goblet cell counts increased (P < 0.001) in duodenum, jejunum and ileum from 1 to 42days, decreasing at 49days, which was also corroborated by the regression analysis. Villus density in the duodenum was greater in the first week, decreased with age and increased again at 42days, probably due to the proximity with egg production onset. The expression of Sglt1 and Glut2 mRNA in the jejunum varied with age. In conclusion, the intestinal mucosa of female Japanese quail developed morphologically until 42days and functionally until earlier ages, indicating an adaptation to the exogenous diet during the first weeks of life.

Mechanisms involved in the development of the small intestine mucosal layer in postnatal piglets.

The use of complementary visualization and measurement techniques allowed accurate description and quantification of changes in the intestinal mucosal architecture and provided a comprehensive outlook on the dynamics of remodelling and maturation processes of the mucosal layer taking place in the small intestine of piglets from birth to weaning. The aim of the study was to examine the early postnatal development of the small intestine in pigs. Three techniques were used: scanning electron microscopy (measurements of villus density and shape, height of enterocytes and microvilli, cell exfoliation, and location of extrusion zones), optical microscopy (cross section, measurement of structures: villus length and width; crypt depth; mucosal thickness), and confocal microscopy (cell localization, apoptosis, exfoliation and migration). The postnatal development of the mucosal layer of the small intestine was reflected in changes in the density, length, width, and shape of villi, crypt depth, replacement of enterocyte population, and arrangement. The presence of deep transverse furrows on villus corpus and vacuolated fetal-type enterocytes in the mucosal layer of the small intestine, which are able to engulf large amounts of colostrum shortly after birth, appears to play an important role in the observed phenomenon of straightening of the villus height and increasing of the villus diameter shortly after birth. We hypothesized that the intestinal mucosal layer is compressed before birth and ready to unfold within a short time after birth.

Citrus Peel Oils Supplementation in Broiler Diet: Effects on Performance, Jejunum Microflora and Jejunum Morphology

ABStRACt This study was carried out to determine citrus peel oils (orange, lemon, bergamot) as food supplementation in different levels on performance, microflora and morphology in broilers. The trial consisted of 1-day-old male and female Ross 308 chicks (250 male 250 female). The study consisted of 10 groups in total and each group was replicated five times. Experimental diets were prepared by adding orange, lemon and bergamot peel oil levels (1,2 and 3 mL/kg) to basal diet. It was observed that the supplementation of citrus peel oils to the diet improved significantly the feed conversion rate. Especially the lowest feed intake and the best feed conversion ratio were received from broilers which were fed 3 mL/kg of orange peel oil. The study shows that the count of Escherichia coli ( E.coli ) and lactic acid bacteria in the jejunum decreased significantly with the supplementation of bergamot peel oil to broilers diets. Citrus peel oil, in contrast to bergamot peel oil, significantly increased lactic acid bacteria count. The highest lactic acid bacteria count was determined in birds fed 3 mL/kg with orange peel oil. In the result of this study, both the length and density of villi and the density of blood and lymphatic capillary in the jejunum increased significantly by dietary 3 mL/kg orange peel oil supplementation. Finally, our results indicate that, especially 3 mL/kg orange peel oil has positive effects on performance, jejunum microflora, and jejunum morphology. It could be advised to supply broilers feed with 3 mL/kg orange peel oil as feed additives.

SORGO EM DIETAS PARA O JUNDIÁ Rhamdia quelen

With the study we had aimed to verify the possible effects of replacing corn by low tannin sorghum in diets for silver catfish Rhamdia quelen on productive performance, carcass chemical composition, size and density of the villi. The experiment was conducted at the Instituto de Pesquisa em Aquicultura Ambiental – InPAA in Toledo - PR. We used 600 fingerlings with average initial weight and length of 4.49 ± 0.80 g and 8.68 ± 0.62 cm respectively, distributed in 24 cages with a capacity of 1m3 of useful volume. We used a completely randomized design with six treatments and four replications, being each experimental unit consisted of a tank with 25 fish. The treatments consisted of six diets with increasing levels of 0; 20; 40; 60; 80 and 100% of sorghum to replace corn. During 114 days, the fingerlings were fed three times a day until apparent satiation. Productive performance, chemical composition, size and density of the villi showed no significant differences (P > 0.05) due to the result replacement of corn by sorghum. Thus, we can concluded that the partial or total replacement of corn by sorghum in diets for silver catfish is feasible because it does not modify the productive performance, the chemical composition of the carcass and the size and density of the intestinal villi.

Effect of Broiler Breeder Age on the Intestinal Mucosa Development of the Embryos at 20 Days of Incubation

This study investigated the effect of broiler breeder age on the morphological development of the small intestine broiler embryos (villus height, crypt depth, microvillus height, and villus density) at 20 day of incubation. Eggs obtained from 30- and 60-wk-old broiler breeders were used. The results showed that embryos from older broiler breeders presented longer villi in the duodenum, jejunum, and ileum compared with younger broiler breeders. In addition, embryos from older broiler breeders presented deeper crypts in the jejunum and ileum, longer microvilli in jejunal enterocytes, and lower villus density (microvillus number/mm2) in the duodenum and ileum than younger breeders. These results suggest that breeder age influences the gut mucosa development of broiler embryos. Embryos from older broiler breeder showed greater development of the small intestine mucosa than those from younger broiler breeder.

Morphology of Cyprid Attachment Organs Compared Across Disparate Barnacle Taxa: Does It Relate to Habitat?

This study used morphometric analyses to compare the structure of the third antennular segment, also called the attachment organ, in cyprid larvae from cirripede species representing a diverse set of taxonomic groups. The aim was to investigate the degree of morphological variation in view of the diversity of habitats, settlement substrata, and modes of life found in the Cirripedia. In all cyprids the third segment features a flat surface (the attachment disc) covered with small cuticular villi thought to function in adhesion. The parameters analyzed were the angle of this disc relative to the long axis of the antennule, its shape (outline), the density of cuticular villi, and the type of cuticular structure encircling the disc. The 10 species studied came from most major groups of cirripedes, and comprised shallow-water forms inhabiting hard bottoms (Capitulum mitella, Pollicipes pollicipes, Semibalanus balanoides, Austrominius modestus, Megabalanus rosa), sublittoral forms (Verruca stroemia, Scalpellum scalpellum), epibiotic forms settling on live, soft tissues (Balanus spongicola, Savignium crenatum), and a parasite (Peltogaster paguri). Significant structural variation was found among the species, but due to limited taxon sampling it was unclear whether the differences relate to ecological factors or phylogenetic affiliation. The disc perimeter is guarded by either a series of long and thin cuticular fringes overreaching the rim of the disc (= a velum) or a few low, but very broad cuticular flaps (= a skirt). The presence of a velum (in all rocky-shore species) or a skirt (all other species) around the attachment disc was the only parameter that was clearly correlated with habitat. The shape of the third antennular segment varied from a symmetrical bell shape with a distally facing attachment disc having a circular disc outline, to segments that were elongated in side view, with a very tilted ventral disc surface having an elliptical disc outline. The bell shape may be most common in forms from rocky shores, but in our test of morphometric parameters only Scalpellum scalpellum (sublittoral), Savignium crenatum (epibiotic in corals), and Peltogaster paguri (parasitic) had shapes that differed significantly from the other species. The density of villi on the attachment disc varied significantly, but also showed no clear-cut correlation with substratum or habitat. Attachment organ structure is clearly the most variable feature in cirripede cyprids. To evaluate the degree to which attachment organ structure is correlated with habitat, settlement substratum, and mode of life, future studies should employ a more refined statistical analysis on an enlarged dataset, with much increased taxon sampling and a more multifaceted definition of ecological variables.

Regulation of dietary glutamine on the growth, intestinal function, immunity and antioxidant capacity of sea cucumber Apostichopus japonicus (Selenka).

The present study examined the effects of dietary glutamine (Gln) on the growth, intestinal function, immunity and antioxidant capacity of sea cucumber Apostichopus japonicus (Selenka). The specific growth rate, intestinal morphology, activity of digestive enzymes, activity and gene expression of lysozyme and antioxidative enzymes of the sea cucumbers were determined after feeding 5 experimental diets with additions of increasing levels of Gln (at 0%, 0.4%, 0.8%,1.2% and 1.6%, respectively) for 60 days. We discovered that the specific growth rate of the sea cucumbers in 0.4%, 0.8% and 1.2% groups increased 35.3%, 27.3% and 24.1%, respectively, compared to the control (0%) group with significant differences. Dietary Gln can improve the intestinal function of the sea cucumbers by increasing the activities of trypsin and lipase in the intestine and the villus height and villus density of the intestine, eventhough significant differences were not observed in some groups. 0.4%-0.8% of dietary Gln can significantly increase the activity of lysozyme (LSZ) in the coelomic fluid of the sea cucumbers. Significant improvements were observed on the SOD activity in coelomic fluid of the sea cucumbers fed diets supplemented with 0.4%-1.6% of Gln compared to the control group. Similarly, the CAT activity in coelomic fluid of the sea cucumbers significantly increased in 0.8%, 1.2% and 1.6% groups compared to the control and 0.4% groups. Change pattern of the activity of CAT was consistent with the change pattern of the expression of CAT gene, indicating the dietary Gln can up-regulate the expression of CAT gene and consequently promote the secretion of CAT. However, the down-regulation of the expression of SOD gene by dietary Gln were observed in almost all of the treatment groups, which is in contrast with the change pattern of the activity of SOD, indicating the negative feedback regulation of the secretion of SOD on the expression of SOD gene. In summary, the suitable supplementation levels of Gln in diets of sea cucumber A. japonicus are 0.4%-0.8%, based on the effectiveness of dietary Gln on the growth, intestinal function, immunity and antioxidant capacity of the sea cucumbers.

Purified cellulose, soybean hulls and citrus pulp as a source of fiber for weaned piglets

Dietary fiber is an important component, which has a direct effect on intake, digestion, and absorption of nutrients; and also alters intestinal microbiota and morphology according to solubility. One digestibility trial and one performance experiment were performed to evaluate the effects of sources of fiber in diets for 21 day weaned piglets. The experimental diets used in both trials consisted of a control diet and diets with purified cellulose, soybean hulls or citrus pulp as a main source of dietary fiber. To evaluate the digestibility of nutrients (Assay 1), the total feces and urine collection method was used. The fiber sources did not affect nutrient digestibility, except for soluble fiber, which increased with the inclusion of citrus (Citrus sinensisL.) pulp. To evaluate performance, morphophysiology and microbiology of the digestive tract of weaned piglets, a total of 32 castrated male piglets was used. Slaughter of animals was implemented at 35 and 50 days of age. The use of soybean (Glycine max L.) hulls and citrus pulp in diets increased the number of goblet cells and the density of villi in the jejunum. The viscosities of stomach and cecum contents increased due to the addition of citrus pulp. Soybean hulls and the citrus pulp included in diets reduced the occurrence of E. coli in the small intestines of piglets slaughtered at 35 days of age. Among the fiber sources, purified cellulose in piglet diets promotes better performance of animals, due to the modulation of the small intestine microbiota, with lower E. coli occurrence resulting in higher villus density.

Post-natal Growth of the Gastrointestinal Tract of the Siberian Hamster: Morphometric Analysis

Post-natal growth of the gastrointestinal tract of the Siberian hamster was studied in newborn and 3-, 7-, 14-, 21-, 42- and 90-day-old animals. Morphometric measurements and calculations were carried out: length and internal surface of gastrointestinal tract segments, size (height, width, surface) and density of villi as well as allometric growth rate of the length and internal surface of the segments with respect to the body mass. The fastest growth rate of the gastrointestinal tract segments was noticed during the first 3 days of the post-natal life. Nevertheless, significant regional differences in their growth rate were found. The increase in the length and internal surface of the large intestine was fastest, while the smallest increase was observed in the oesophagus. All segments of the gastrointestinal tract except oesophagus exhibited a positive allometric relationship to the body mass from birth till final weaning, whereas during the post-weaning period, the increase was isometric. Thus, at birth, the gastrointestinal tract segments were relatively smaller compared with those observed in adults, but then, the gastrointestinal tract grew faster than the rest of the body and reached its adult proportions just before the transition to solid food. Most probably, reaching the adult structure of the gastrointestinal tract before the final weaning is an essential condition for the proper growth of an organism after the weaning.