Foraging strategies of black-fronted titi monkeys (<Emphasis Type="Italic">Callicebus nigrifrons</Emphasis>) in relation to food availability in a seasonal tropical forest

Many primates have to cope with a temporal scarcity in food availability that shapes their foraging strategies. Here we investigated the changes in diet, activity, and ranging behavior of a group of black-fronted titi monkeys (Callicebus nigrifrons) according to the availability of the main high-nutritional-density item in their diet and the foraging strategy adopted when this food is scarce. We monitored one habituated group using instantaneous scan sampling over 1 year (533 h of observation, 61 days) in a seasonal tropical forest fragment (245 ha). We simultaneously collected data on food availability with fruit traps. The titi monkeys consumed fleshy fruits, the main high-nutritional-density item of their diet, in accordance with its availability, and the availability of this item modulated the ingestion of vegetative plant parts, a relatively low-nutritional-density food. During high fleshy fruit availability, the titi monkeys consumed more fleshy fruits, flowers, and invertebrates. They also traveled more, but concentrated their activity in a central area of their home range. Conversely, during fleshy fruit scarcity, they increased the breadth of their diet, switching to one richer in seeds and vegetative plant parts, and with greater plant diversity. At the same time, they reduced most energy-demanding activities, traveling less and over shorter distances, but using their home range more broadly. Corroborating the optimal foraging theory, titi monkeys altered foraging strategies according to temporal food fluctuations and responded to low fleshy fruit availability by changing their diet, activity, and ranging behavior. The adoption of a low-cost/low-yield strategy allowed us to classify them as energy minimizers.     

Ecological Flexibility in Boutourlini’s Blue Monkeys (Cercopithecus mitis boutourlinii) in Jibat Forest, Ethiopia: A Comparison of Habitat Use, Ranging Behavior, and Diet in Intact and Fragmented Forest

Comparisons of the behavior and ecology of primates living in intact and fragmented forest are critical to the development of conservation strategies for the many primate taxa threatened by habitat loss. From July 2009 to April 2010, we investigated the habitat use, ranging behavior, and diet of two groups of Boutourlini’s blue monkeys (Cercopithecus mitis boutourlinii), a subspecies endemic to western Ethiopia, whose habitats had experienced different levels of disturbance at Jibat Forest. Forest Group occupied primarily continuous tree-dominated forest with little human disturbance whereas Fragment Group inhabited a heavily degraded 2- to 3-km² forest fragment nearly surrounded by farmland and connected tenuously to the continuous forest by a narrow corridor of riverine forest. Mean daily path lengths for both groups were nearly identical (Forest Group: 799 m; Fragment Group: 783 m) and exhibited little seasonal variability. The mean home range areas of Forest Group and Fragment Group were 72.0 and 61.2 ha, respectively. Forest Group (N?=?2232 feeding records) fed mostly on fruits (52.5 %), though they also ate animal prey (14.7 %), young leaves (11.1 %), shoots (8.7 %), and flowers (7.3 %). In contrast, fruits accounted for only 17.0 % of Fragment Group’s diet (N?=?2903 feeding records), with shoots (29.8 %), young leaves (17.1 %), animal prey (13.1 %), seeds (9.6 %), and flowers (6.8 %) also making substantial contributions to their diet. Only Fragment Group engaged in crop raiding, consuming seeds from barley and wheat extensively (33–41 % of diet) during 2 mo. Fragment Group (N?=?33) ate more plant species than Forest Group (N?=?24), though both groups exploited a small number of plant species relative to other subspecies of blue monkeys. Our study revealed that, like most other blue monkey subspecies, Boutourlini’s blue monkeys are quite flexible in the habitats they occupy as well as in their foraging habits. Despite this ecological flexibility, the long-term conservation of Boutourlini’s blue monkey is far from assured given its limited distribution, the rapidly growing human population, and the high rates of forest clearance in western Ethiopia.     

Polyspecific associations between squirrel monkeys (Saimiri sciureus) and other primates in eastern Amazonia

One of the most common types of polyspecific association observed in Neotropical primate communities is that between squirrel monkeys (Saimiri) and capuchins (Cebus). The present study focused on association patterns in two Saimiri sciureus groups in eastern Brazilian Amazonia, between March and October, 2009. The associations were analyzed in terms of the species involved, the degree of association, and niche breadth and overlap. The study involved two S. sciureus groups (B4 and GI) on the right and left bank of the Tocantins River, respectively, within the area of the Tucuruí reservoir in southeastern Pará. Relations between species were classified as associations (individuals within 50 m and moving in the same direction), and encounters (individuals within 50 m and no coordinated movement). Group B4 was in association with Cebus apella during 100% of monitoring, and with Chiropotes satanas in 20.2%. By contrast, Group GI associated with Cebus 54.8% of the time, and with Chiropotes utahickae 2.5%. Encounters with Alouatta belzebul and Saguinus niger were recorded at both sites, with Aotus azarae and Dasyprocta prymnolopha at B4, and with Callicebus moloch, Dasyproct aleporina, Mazama gouazoubira, and Nasua nasua at GI. Overall, Saimiri had a broader niche than Cebus in terms of vertical spacing and diet, but not for substrate use. This pattern did not appear to be affected by association. While group GI spent significantly (P < 0.05) more time in association with Cebus during the wet season, group B4 associated with Chiropotes more during the dry season. Despite the higher association rates, niche overlap was greater for all variables at B4. This may reflect differences in the ranging and foraging patterns at the two sites, and the varying potential benefits of association for Saimiri.     

Ginseng Panaxoside Rb1 Reduces Body Weight in Diet-Induced Obese Mice

Crude extracts from ginseng demonstrated anti-obesity properties. Ginsenoside Rb1 is the main component of ginseng, however, there are only few studies examining its effects in obesity. In the present study, we evaluated its potential anti-obesity effects in the murine model of diet-induced obesity. Seventy male C57BL/6 mice were randomly divided to consume for 12 weeks either chow diet (N = 8) or high-fat (HF) diet (N = 62). The latter mice were then divided into four groups: diet-induced obesity group (DIO; N = 10), obesity-resistant group (OR; N = 10), HF group (N = 5), and the group whose diet was changed from HF to normal diet (DC; N = 5). Intraperitoneal injections of Rb-1 were administered daily to mice in the DIO and OR groups for 3 weeks. Body weight and energy intake were monitored, and fasting blood glucose, lipids, neuropeptide Y, Y2 receptor, and peptide YY were quantified. Compared with HF group, weight gain and food intake of DIO mice with Rb-1 injection was significantly decreased (p < 0.05). Further, levels of blood glucose and some lipids were also decreased in DIO-Rb1 group compared with HF group. Furthermore, Rb1 was also found to modulate serum levels of PYY and NPY, and mRNA expression of NPY, Y2 receptor and PYY in tissue samples of DIO mice. Taken together, ginsenoside Rb1 may be useful in the treatment of obesity via modifying the serum content and mRNA expression of NPY, Y2 receptor and PYY.     

Seasonal Variation in the Activity and Dietary Budgets of Cat Ba Langurs (<Emphasis Type="Italic">Trachypithecus poliocephalus</Emphasis>)

Primate activity budgets are dictated by food availability and distribution; thus primates living in seasonal environments must adapt their behaviors to accommodate fluctuations in resources. Cat Ba langurs (Trachypithecus poliocephalus), a Critically Endangered Asian colobine and a member of the limestone langur group (francoisi superspecies group within genus Trachypithecus), live only in fragmented and disturbed habitats on Cat Ba Island, northeastern Vietnam. This study aimed to assess the behaviors and diet of Cat Ba langurs by group, age, sex, and season. We predicted they would have high rates of inactivity and foraging, low rates of social behaviors, with seasonal variation that reflects an energy-maximizing strategy. We conducted behavioral observations through scan sampling over an 11-month period and found that Cat Ba langurs spent a significant portion of their day inactive (57 %) followed by foraging (18 %), socializing (13 %), locomoting (10 %), and engaging in “other” behaviors (2 %). Their diet was made up primarily of leaves (83 %) followed by flowers (8 %), fruit (6 %), and stems (3 %). We found groups to differ in diet and activity, which is likely owing to differences in demographics and home range between groups. Seasonally, the animals ate more leaves and spent more time foraging in the dry season than the wet season, suggesting that they are energy maximizers. Cat Ba langurs have activity and dietary budgets similar to those of other limestone langurs, and respond to a presumed seasonal fluctuation in food availability similarly.     

Size,Site Fidelity,and Overlap of Home Ranges and Core Areas in the Socially Monogamous Owl Monkey (Aotus azarae) of Northern Argentina

In addition to environmental factors, social variables such as group size may play an important role in explaining primate ranging patterns. In this study we investigated range sizes, site fidelity, and range overlaps of owl monkeys (Aotus azarae) in Northern Argentina. We calculated the size of home range and core areas for 18 groups in our study area. For the six most intensively studied groups we tested whether precipitation as a crude proxy for food availability or group size had an influence on range size, assessed the degree of site fidelity by quantifying overlaps of annual ranges and core areas, and calculated the amount of range overlap between neighboring groups for each year. We used the kernel density estimation method to calculate home ranges as 90% kernel and core areas as 50% kernel. Home range size (mean ± SD) was 6.2 ha (± 1.8) and core area size 1.9 (± 0.6). Rainfall and group size were not statistically significant predictors of range sizes. Site fidelity was high, with a range overlap of 82% (± 11) between consecutive years. Neighboring groups overlapped over 48% (± 15) of the outer parts of their group ranges and 11% (± 15) of their core areas. We found no evidence that larger groups occupy larger areas than smaller groups, suggesting that food availability might be above a critical threshold for owl monkeys so that larger groups do not need to extend their foraging areas to meet their energy requirements. Our findings indicate that ranges remain stable over several years as groups visit the same locations of fruit trees within their range. We showed that owl monkeys exhibit a considerable degree of range overlap. However, we suggest that this range overlap might be spatial rather than temporal, which maximizes access to clumped feeding resources in overlapping areas that are used at distinct times, while excluding other males from access to females in exclusively used areas.     

Behavioral activities and diet of Azaras’s capuchin monkey,Sapajus cay (Illiger, 1815), in a forest remnant of the Brazilian Cerrado

ABSTRACT

Azaras’s capuchin monkey (Sapajus cay) is a poorly studied species in ecological aspects. We investigated behavioral activities and diet of a group of S. cay in a remnant of the Brazilian Cerrado. We sought to identify the most frequent behavior that the group engaged in, as well as to verify possible differences in behavioral patterns and diet between adult males and females. From January to July 2012 we collected behavioral and foraging data for a group of 21 individuals using scan sampling. Behaviors and food items consumed were analyzed using percentages and two proportions Z-tests to assess differences between males and females. We obtained 878 scans in approximately 202 hours of sampling effort, resulting in 4,159 individual activity records of capuchin monkeys. The group allocated time to traveling (41.3%), resting (25.5%), feeding (14.3%), foraging (13.7%), and social activities (5.1%). Females spent more time foraging and feeding, while males spent more time resting. Fruits (61.4%), invertebrates (15.3%), and seeds (14.3%) were the most common food items consumed. We did not find differences in food consumption between sexes. Behavioral activities may be influenced by habitat quality of the studied area, opportunistic habits, and plasticity in the diet.     

Dietary supplementation with monosodium glutamate is safe and improves growth performance in postweaning pigs

Dietary intake of glutamate by postweaning pigs is markedly reduced due to low feed consumption. This study was conducted to determine the safety and efficacy of dietary supplementation with monosodium glutamate (MSG) in postweaning pigs. Piglets were weaned at 21 days of age to a corn and soybean meal-based diet supplemented with 0, 0.5, 1, 2, and 4 % MSG (n = 25/group). MSG was added to the basal diet at the expense of cornstarch. At 42 days of age (21 days after weaning), blood samples (10 mL) were obtained from the jugular vein of 25 pigs/group at 1 and 4 h after feeding for hematological and clinical chemistry tests; thereafter, pigs (n = 6/group) were euthanized to obtain tissues for histopathological examinations. Feed intake was not affected by dietary supplementation with 0–2 % MSG and was 15 % lower in pigs supplemented with 4 % MSG compared with the 0 % MSG group. Compared with the control, dietary supplementation with 1, 2 and 4 % MSG dose-dependently increased plasma concentrations of glutamate, glutamine, and other amino acids (including lysine, methionine, phenylalanine and leucine), daily weight gain, and feed efficiency in postweaning pigs. At day 7 postweaning, dietary supplementation with 1–4 % MSG also increased jejunal villus height, DNA content, and antioxidative capacity. The MSG supplementation dose-dependently reduced the incidence of diarrhea during the first week after weaning. All variables in standard hematology and clinical chemistry tests, as well as gross and microscopic structures, did not differ among the five groups of pigs. These results indicate that dietary supplementation with up to 4 % MSG is safe and improves growth performance in postweaning pigs.     

Observations on two types of neotropical primate intertaxa associations

During a socioecological field study of Colombian spider monkeys, data were collected on spatial associations and social and ecological interactions among free-ranging Ateles belzebuth, Alouatta seniculus, Cebus apella, and Saimiri sciureus. The most frequently observed associations occurred between groups of squirrel and capuchin monkeys. Saimiri-Cebus associations were seen at all times of day and year, but no intertaxa play, passive body contact, or grooming interactions were observed. The Saimiri-Cebus association was paralleled by one between Saimiri and the small hawk, Harpagus bidentatus, and sometimes other insectivorous birds. These associations may be based in part on a complex balance of both mutual and one-sided foraging advantages. Less frequent associations between Ateles and Alouatta were based on mutual attraction to specific fruiting trees or contacts occurring on travel routes. Unlike the more frequently observed associations between Saimiri and Cebus, those between Ateles and Alouatta included both positive and negative interactions; for example, mutual play, grooming, and olfactory investigation as well as threats, chases, and supplantations.     

Living together: behavior and welfare in single and mixed species groups of capuchin (Cebus apella) and squirrel monkeys (Saimiri sciureus)

There are potential advantages of housing primates in mixed species exhibits for both the visiting public and the primates themselves. If the primates naturally associate in the wild, it may be more educational and enjoyable for the public to view. Increases in social complexity and stimulation may be enriching for the primates. However, mixed species exhibits might also create welfare problems such as stress from interspecific aggression. We present data on the behavior of single and mixed species groups of capuchin monkeys (Cebus apella) and squirrel monkeys (Saimiri sciureus) housed at the Living Links to Human Evolution Research Centre in the Royal Zoological Society of Scotland's Edinburgh Zoo. These species associate in the wild, gaining foraging benefits and decreased predation. But Cebus are also predators themselves with potential risks for the smaller Saimiri. To study their living together we took scan samples at ≥15 min intervals on single (n=109) and mixed species groups (n=152), and all occurrences of intraspecific aggression and interspecific interactions were recorded. We found no evidence of chronic stress and Saimiri actively chose to associate with Cebus. On 79% of scans, the two species simultaneously occupied the same part of their enclosure. No vertical displacement was observed. Interspecific interactions were common (>2.5/hr), and equally divided among mildly aggressive, neutral, and affiliative interactions such as play. Only one aggressive interaction involved physical contact and was non‐injurious. Aggressive interactions were mostly (65%) displacements and vocal exchanges, initiated almost equally by Cebus and Saimiri. Modifications to the enclosure were successful in reducing these mildly aggressive interactions with affiliative interactions increasing in frequency and diversity. Our data suggest that in carefully designed, large enclosures, naturally associating monkeys are able to live harmoniously and are enriched by each other. Am. J. Primatol. 72:33–47, 2010. © 2009 Wiley‐Liss, Inc.     

Effect of citrulline on muscle functions during moderate dietary restriction in healthy adult rats

Low calorie diets are designed to reduce body weight and fat mass, but they also lead to a detrimental loss of lean body mass, which is an important problem for overweight people trying to lose weight. In this context, a specific dietary intervention that preserves muscle mass in people following a slimming regime would be of great benefit. Leucine (LEU) and Citrulline (CIT) are known to stimulate muscle protein synthesis (MPS) in post-prandial and post-absorptive state, respectively. This makes them interesting bioactive components to test in the context of dietary restriction. We tested the concept of combining LEU and CIT in adult female rats. We postulated that the sequential administration of LEU (mixed in chow) and CIT (given in drinking water before a rest period) could be beneficial for preservation of muscle function during food restriction. Sixty female rats (22 weeks old) were randomized into six groups: one group fed ad libitum with a standard diet (C) and five food-restricted groups (60 % of spontaneous intake for 2 weeks) receiving a standard diet (R group), a CIT-supplemented diet (0.2 or 1 g/kg/day, CIT0.2 group and CIT1 group, respectively), a LEU-supplemented diet (1.0 g/kg/day) or a CIT + LEU-supplemented diet (CIT + LEU 1.0 g/kg/day each). At the end of the experiment, body composition, muscle contractile properties and muscle protein synthesis (MPS) rate were studied in the tibialis anterior muscle. Dietary restriction tended to decrease MPS (R: 2.5 ± 0.2 vs. C: 3.4 ± 0.4 %/day, p = 0.06) and decrease muscle strength (R: 3,045 ± 663 vs. C: 5,650 ± 661 A.U., p = 0.03). Only CIT administration (1 g/kg) was able to restore MPS (CIT1: 3.4 ± 0.3 vs. R: 2.5 ± 0.2 %/day, p = 0.05) and increase muscle maximum tetanic force (CIT1: 441 ± 15 vs. R: 392 ± 22 g, p = 0.05) and muscle strength (CIT1: 4,259 ± 478 vs. R: 3,045 ± 663 A.U., p = 0.05). LEU had no effect and CIT + LEU supplementation had few effects, limited to adipose mass and fatigue force. The results of this study highlight the ability of CIT alone to preserve muscle function during dietary restriction. Surprisingly, LEU antagonized some effects of CIT. The mechanisms involved in this antagonistic effect warrant further study.     

Effects of Different Sources and Levels of Zinc on Growth Performance,Nutrient Digestibility,and Fur Quality of Growing-Furring Male Mink (<Emphasis Type="Italic">Mustela vison</Emphasis>)

The objective of this study was to investigate the effects of different sources and levels of zinc (Zn) on growth performance, nutrient digestibility, serum biochemical parameters, and fur quality in growing-furring male mink. Animals in the control group were fed a basal diet with no Zn supplementation. Mink in the other nine treatments were fed the basal diet supplemented with Zn from either grade Zn sulfate (ZnSO₄·7H₂O), Zn glycinate (ZnGly), or Zn pectin oligosaccharides (ZnPOS) at concentrations of either 100, 300, or 900 mg Zn/kg dry matter. One hundred and fifty healthy 15-week-old male mink were randomly allocated to ten dietary treatments (n = 15/group) for a 60-day trial from mid-September to pelting in December. Mink in the Zn-POS groups had higher average daily gain than those in the control group (P < 0.05). Zn source slightly improved the feed/gain (P = 0.097). N retention was increased by Zn addition (P < 0.05). Mink supplemented with dietary Zn had higher (P < 0.05) pancreas Zn level than the control group. Fur length was greater (P < 0.05) in ZnGly and ZnPOS groups compared with the control. In addition, fur length and fur density increased (linear, P < 0.05) with Zn supplementation in the diet. In conclusion, our data show that dietary Zn addition improves growth performance by increasing nitrogen retention and fat digestibility in growing-furring mink and Z-POS is equally bioavailable to mink compared to ZnGly.     

Effects of High-Pressure Oxygen Therapy on Brain Tissue Water Content and AQP4 Expression in Rabbits with Cerebral Hemorrhage

To investigate the effects of different atmosphere absolutes (ATA) of high-pressure oxygen (HPO) on brain tissue water content and Aquaporin-4 (AQP4) expression in rabbits with cerebral hemorrhage. 180 New Zealand white rabbits were selected and randomly divided into normal group (n = 30), control group (n = 30) and cerebral hemorrhage group (n = 120), and cerebral hemorrhage group was divided into group A, B, C and D with 30 rabbits in each group. The groups received 1.0, 1.8, 2.0 and 2.2 ATA of HPO treatments, respectively. Ten rabbits in each group were killed at first, third and fifth day to detect the brain tissue water content and change of AQP4 expression. In cerebral hemorrhage group, brain tissue water content and AQP4 expression after model establishment were first increased, then decreased and reached the maximum on third day (p < 0.05). Brain tissue water content and AQP4 expression in control group and cerebral hemorrhage group were significantly higher than normal group at different time points (p < 0.05). In contrast, brain tissue water content and AQP4 expression in group C were significantly lower than in group A, group B, group D and control group (p < 0.05). In control group, AQP4-positive cells significantly increased after model establishment, which reached maximum on third day, and positive cells in group C were significantly less than in group A, group B and group D. We also found that AQP4 expression were positively correlated with brain tissue water content (r = 0.719, p < 0.05) demonstrated by significantly increased AQP4 expression along with increased brain tissue water content. In conclusion, HPO can decrease AQP4 expression in brain tissue of rabbits with cerebral hemorrhage to suppress the progression of brain edema and promote repairing of injured tissue. 2.0 ATA HPO exerts best effects, which provides an experimental basis for ATA selection of HPO in treating cerebral hemorrhage.     

Effect of gibberellic acid- and water-based pre-soaking treatments under different temperatures and photoperiods on the seed germination of Allium stracheyi Baker: An endangered alpine species of Central Himalaya,India

Allium stracheyi Baker (Alliaceae, 2600–3000 m asl), an endangered species of Central Himalaya, India, has low seed germination in its natural habitat. This study is an attempt to improve seed germination by determining the seed viability with a low mean germination time (MGT) and germination index (GI) under optimum temperature, light, and pre-soaking treatments. The seeds were pre-soaked in hot water (80°C), cold water (10°C), and gibberellic acid (GA₃ at 50 and 100 mg/l) for 24 h and subjected to light (12 h light and 12 h dark) and continuous dark (24 h) conditions with different temperature regimes (10, 15, 20, 25, and 30°C). The viability varied between 66.0% and 69.67% and declined rapidly after 12 months of storage. Our studies suggest that the 100 mg/l GA₃ treatment was beneficial for seed germination and seedling growth. Pre-soaking in a 100 mg/l GA₃ solution and incubation at 20°C under light conditions enhanced the germination significantly (p < 0.05) and resulted in the highest (97.3%) germination with the lowest MGT = 5.7 days, with GI = 8.11. The recommendations of this study support the conservation of alpine A. stracheyi via simple and cost-effective techniques for optimal seed germination.     

Responses of squirrel monkeys to seasonal changes in food availability in an eastern Amazonian forest

Tropical forests are characterized by marked temporal and spatial variation in productivity, and many primates face foraging problems associated with seasonal shifts in fruit availability. In this study, I examined seasonal changes in diet and foraging behaviors of two groups of squirrel monkeys (Saimiri sciureus), studied for 12 months in Eastern Brazilian Amazonia, an area characterized by seasonal rainfall. Squirrel monkeys were primarily insectivorous (79% of feeding and foraging time), with fruit consumption highest during the rainy season. Although monkeys fed from 68 plant species, fruit of Attalea maripa palms accounted for 28% of annual fruit-feeding records. Dietary shifts in the dry season were correlated with a decline in ripe A. maripa fruits. Despite pronounced seasonal variation in rainfall and fruit abundance, foraging efficiency, travel time, and distance traveled remained stable between seasons. Instead, squirrel monkeys at this Eastern Amazonian site primarily dealt with the seasonal decline in fruit by showing dietary flexibility. Consumption of insects, flowers, and exudates increased during the dry season. In particular, their foraging behavior at this time strongly resembled that of tamarins (Saguinus sp.) and consisted of heavy use of seed-pod exudates and specialized foraging on large-bodied orthopterans near the forest floor. Comparisons with squirrel monkeys at other locations indicate that, across their geographic range, Saimiri use a variety of behavioral tactics during reduced periods of fruit availability.     

The Effects of Direct-fed Microbial Supplementation,as an Alternative to Antibiotics,on Growth Performance,Intestinal Immune Status,and Epithelial Barrier Gene Expression in Broiler Chickens

The objective of this study was to investigate the effects of Bacillus subtilis-based probiotic supplementation in broiler chicken diets on growth performance, feed efficiency, intestinal cytokine, and tight junction (TJ) protein mRNA expression. Zero-day-old broiler chicks (n = 140) were randomly assigned to one of five dietary treatments: basal diet (CON); basal diet supplemented with either antibiotic bacitracin methylene disalicylate (BMD); or probiotics, namely, B. subtilis strain 1781 (PB1), a combination of B. subtilis strain 1104 + strain 747 (PB2), or B. subtilis strain 1781 + strain 747 (PB3). Body weight and feed intake were measured at 14 days of age, and the feed conversion ratio (FCR) was calculated. At 14 days of age, ileal samples were collected and used for intestinal cytokine, TJ protein, and mucin gene expression analysis using qRT-PCR. The chickens supplemented with antibiotic (BMD) and B. subtilis strain 1781 alone (PB1) had significantly higher body weights compared to controls of the same age. Dietary supplementation with antibiotic (BMD) or probiotics (PB1, PB2, PB3) significantly improved the feed efficiency as evidenced by decreased FCR compared to controls. No differences were observed in the expression of IL1β, IL17F, IFNγ, and MUC2 gene among the different treatment groups. However, elevated expression of IL6 (BMD, PB1, PB2), IL8 (PB2), and TNFSF15 (PB1, PB2, PB3) compared to controls was observed in the ileum. IL2 and IL10 expression was upregulated in chicks in the PB2 and PB3 groups, and IL4 was elevated in the PB1 group. IL13 was elevated in all probiotic-fed groups (PB1, PB2, PB3). Probiotic supplementation was also shown to significantly increase the expression of TJ proteins JAM2, ZO1 (PB2, PB3), and occludin (PB1, PB2). Taken together, B. subtilis supplementation altered intestinal immune activity and influenced gut barrier integrity through increased tight junction gene expression.     

Feeding habits of the Atlantic bluefin tuna, Thunnus thynnus (L. 1758), in the central Mediterranean Sea (Strait of Messina)

The study of feeding habits of the Atlantic bluefin tuna was carried out in 123 specimens, ranging from 115 to 222 cm fork length (FL) and collected during spring seasons of 2010 and 2011 in the central Mediterranean Sea (Strait of Messina). The analysis of stomach contents allowed us to identify 91 taxa of prey items, mainly belonging to Teleostea (54), Cephalopoda (20) and Crustacea (13). The percentage of index of relative abundance (IRI) shows the highest values for the myctophid Hygophum benoiti (%IRI = 22.854) and the stomiid Chauliodus sloani (%IRI = 15.124), followed by the oegopsid squid Illex coindetii (%IRI = 14.316). The broad spectrum of prey items could suggest a generalist behavior of this predator, with several species that occasionally occurs in its diet. However, if prey are grouped into food categories, the importance of mesopelagic and benthopelagic fishes can be appreciated (54.41 % of %IRI). The assessment of the hypothetical foraging rhythm of the Atlantic bluefin tuna highlighted that its feeding activity is concentrated on diel migrating fauna during night and on larger preys upon daylight. The predation on the high-energetic food as mesopelagic and bathypelagic fishes during the pre-spawning and the spawning period may bring an energetic advantage in tuna metabolism and gonadal maturation     

Proportion of higher trophic-level prey in the diet of Pacific walruses (Odobenus rosmarus divergens)

During nutritionally stressful situations, Pacific walruses (Odobenus rosmarus divergens) may switch from preying on benthic invertebrates to higher trophic-level prey (HTLP) (e.g., pinnipeds and/or seabirds). We applied a Bayesian mixing model to stable isotope (C and N) data from analyses of various tissues (tongue and lumbar muscle, skin, and liver) to quantify the proportional contribution of HTLP to walruses (n = 293 individuals). The mode contribution of HTLP to walrus diet was ~22 % (±10 %) based on muscle mixing models, which is consistent with results from contaminant studies of Atlantic walruses (Odobenus rosmarus rosmarus), but higher than estimates based on historical stomach content analyses of Pacific walruses. A broader range in the proportion of HTLP (0–60 %) shown by mixing models using stable isotope data from liver and skin of walruses indicated they pursue an opportunistic foraging strategy. Data from the HTLP-consuming walruses were comparable with our stable isotope data of a known “seal-eating” walrus. No significant difference was evident between the estimated contributions of HTLP to the diet of male versus female walruses (P > 0.01). This finding suggests that changes in diet base for walruses are not influenced by the sex of the predator.     

The role of resveratrol on skeletal muscle cell differentiation and myotube hypertrophy during glucose restriction

Considering the well-known antioxidant properties of statins, it seems important to assess their impact on major markers of oxidative stress (superoxide anion radical, nitric oxide, and index of lipid peroxidation) to compare the antioxidative potentials of atorvastatin and simvastatin during the different degrees of hyperhomocysteinemia (HHcy) in rats. This study was conducted on adult male Wistar albino rats (n = 90; 4 weeks old; 100 ± 15 g body mass) in which HHcy was achieved by dietary manipulation. For 4 weeks, the animals were fed with one of the following diets: standard rodent chow, diet enriched in methionine with no deficiency in B vitamins (folic acid, B6, and B12), or diet enriched in methionine and deficient in B vitamins (folic acid, B6, and B12). At the same time, animals were treated with atorvastatin at doses of 3 mg/kg/day i.p. or simvastatin at doses of 5 mg/kg/day i.p. Levels of superoxide anion radical and TBARS were significantly decreased by administration of simvastatin in normal and high-homocysteine (Hcy) groups (p < 0.05). At 4 weeks after feeding with purified diets, the concentrations of the GSH, CAT, and SOD antioxidants were significantly affected among all groups (p < 0.05). Our results indicated that statin therapy had variable effects on the redox status in hyperhomocysteinemic rats, and simvastatin demonstrated stronger antioxidant effects than did atorvastatin.