Days Of Feeding Period Research Articles

The Enrichment of Hen Eggs with ω-3 Fatty Acids

A study was conducted to determine the omega-3 fatty acid compositions of enriched eggs obtained from hens by feeding flaxseed and fish oil. Laying hens were fed a diet containing fish oil (FOD) (1.5%) or a mixture of flaxseed (10%) and fish oil (FFOD) (1.5%) for 15 and 30 days. Another group was fed commercial diet as a control. Eicosapentaenoic acid (EPA) and docosapentaenoic acid (DPA) were not determined in the control group's eggs. However, the EPA level was 0.87% and 0.82% in the FOD group's eggs and 0.49% and 0.55% in the FFOD group's eggs, obtained after a 15- and 30-day feeding period, respectively. Corresponding values for DPA were 0.45% and 0.50% in the FOD group's eggs and 0.41% and 0.44% in the FFOD group's eggs. Docosahexaenoic acid contents of eggs obtained from the FOD group were 4.85% and 4.92% after a 15- and 30-day feeding period, respectively, compared with 3.29% and 3.91% in the FFOD group's eggs and 1.03% in the control group's eggs. The alpha-linolenic acid content of eggs was 0.45% and 0.49% in the FOD group's eggs after a 15- and 30-day feeding period, respectively, and 0.43% in the control group's eggs, whereas it was 3.61% and 4.10%, respectively, in the FFOD group's eggs.

Effect of dietary tea catechins supplementation in goats on the quality of meat kept under refrigeration

Liuyang black male goats were used to examine the effects of TC inclusion on lipid oxidation and fresh meat quality of goats. Forty goats were randomly divided into four equal groups (ten animals in each group) and assigned to four experiment diets with TC supplementation at four levels (0, 2000, 3000 and 4000 mg TC/kg feed). After 60 days of feeding period, all goats were slaughtered and sampled. The results showed that dietary TC supplementation had significant ( P < 0.05) effect on plasma total antioxidant status (TAS) at days 40 and 60, lipid oxidation of M. longissimus dorsi (LD), gluteus medius (GM) and semimemberanosus (SM), pH value of GM and SM at 24 h postmortem, intramuscular fat (IMF) of SM, drip loss percentage of GM and SM, and total haem pigment content (THP) of LD and SM. In conclusion, suitable dietary TC level could inhibit lipid oxidation, decrease drip loss of fresh meat and improve meat colour stability in goat, moreover, dietary TC inclusion influences muscle pH values and IMF at some degree, but different muscle types showed different trend to change, and the quality of LD was relatively stable according to overall evaluation.

High Fiber Diet Supplemented with Rice Bran Hemicellulose May Reduce Daidzein Absorption in Mice

Much attention has focused on the health benefits of isoflavone. Investigating the absorption and metabolism of isoflavonoids is essential for understanding their biological activity. We explored the effect of a high fiber diet containing rice bran hemicellulose on the plasma and cecal isoflavonoids in mice. Mice were fed a 5% rice bran hemicellulose and 5% cellulose-0.1% daidzein diet (RBI diet) or a 5% cellulose-0.1% daidzein diet (CI diet) for 30 days. After the 30-day feeding period, the mice were sacrificed and blood and cecal contents were collected. The plasma isoflavonoids and plasma total cholesterol concentrations were measured. The plasma daidzein concentrations were significantly lower in the RBI group compared to the CI group. In contrast, there were no significant differences in the plasma equol concentrations or plasma total cholesterol concentrations between the RBI and CI groups. Binding affinity against isoflavonoids and/or the bulking effect in the gut might be related with the reduction in plasma daidzein concentration in the RBI group.

Salmon calcitonin reduces food intake through changes in meal sizes in male rhesus monkeys

Amylinergic mechanisms are believed to be involved in the control of appetite. This study examined the effects of the amylin agonist, salmon calcitonin, on food intake and meal patterns in adult male rhesus monkeys. Fifteen minutes before the onset of their 6-h daily feeding period, monkeys received intramuscular injections of various doses of salmon calcitonin (0.032, 0.056, 0.1, 0.32, and 1 microg/kg) or saline. Salmon calcitonin dose dependently reduced total daily and hourly food intake, with significant decreases at the 0.1, 0.32, and 1 microg/kg doses. Daily food intake was reduced by approximately 35%, 62%, and 96%, at these doses, respectively. An analysis of meal patterns revealed that size of the first meal was significantly reduced across the dose range of 0.056 to 1 microg/kg, while average meal size was reduced with the 0.32 and 1 microg/kg doses. Meal number was only affected at the 1 microg/kg dose. Repeated 5-day administration of the 0.1 microg/kg dose resulted in a reduction in daily food intake only on injection day 2, while significant reductions in food intake were observed on all five injection days with a 0.32 microg/kg dose. Daily food intake was also reduced for 1 day after the termination of the 5-day injections of the 0.32 microg/kg salmon calcitonin dose. These sustained reductions in intake were expressed through decreases in meal size. These data demonstrate that salmon calcitonin acutely and consistently decreases food intake mainly through reductions in meal sizes in nonhuman primates.

The GLP-1 agonist exendin-4 reduces food intake in nonhuman primates through changes in meal size

Exendin-4 (Ex4), a long-acting glucagon-like peptide-1 (GLP-1) receptor agonist, has been shown to reduce food intake and suppress gastric emptying in rodents and humans. In this study we investigated the effects of peripheral administration of Ex4 on food intake and meal patterns in adult male rhesus macaques. Rhesus macaques (n = 4) that had been trained to lever press for food pellets were injected intramuscularly 15 min before the start of their 6-h daily feeding period. Ex4 was given at doses of 0.10, 0.32, 0.56, 1.0, and 3.0 microg/kg. Ex4 suppressed food intake in a dose-dependent manner, with the 3.0 microg/kg dose completely preventing feeding during the 6-h period and the 0.10 microg/kg dose suppressing intake by 17%. Doses of 0.32, 0.56, 1.0, and 3.0 microg/kg caused significant reductions in cumulative intake at all six hourly time points. Ex4 inhibited food intake through a specific effect on meal size. Meal size was significantly reduced in a dose-dependent manner with significant reductions at the 0.32 and 1.0 microg/kg doses (P < 0.05). Day 2 and 3 intakes returned to baseline levels with no compensation for Ex4-induced feeding suppression. Administration of doses of 0.32 and 0.56 microg/kg Ex4 over 5 consecutive days led to sustained reductions in intake with no evidence of compensation. Again, these reductions were due to specific effects on meal size. These results demonstrate that activation of GLP-1 pathways has potent effects on the controls of meal size and overall food intake in a nonhuman primate model.

The Hepatoprotective Effect of Carrot (Daucus Carota L.) as Antioxidant on Intoxicated rats with Ccl4

ABSTRACT The effect of feeding dry powder of carrot at three graded concentrations (5,10,20 %) mixed with the basal diet to carbon tetrachloride (Ccl4) intoxicated male rats for 4 weeks was studied. Intoxication of rats was done by s/c injection of Ccl4 (1 ml/kg) in the first (treatment group) and the last (prophylaxis ) two days of feeding period, as a single dose per day. Results of this study revealed that prophylaxis is more powerful than treatment groups. Both groups significantly increased feed intake, body weight gain percent and feed efficiency ratio. Biochemical analyses cleared that carrot supplementation to diet significantly lowered serum total cholesterol, triglycerides and LDL cholesterol, but increased HDL cholesterol. Serum liver enzymes( AST and ALT) as well as concentrations of urea nitrogen, uric acid and creatinine decreased in rats fed carrot supplemented diet .Histopathological examinations of liver and kidneys of these rats showed a decrease or amelioration of pathological lesions and damages caused by Ccl4 intoxicated rats.

Effects of boar presence on agonistic behavior, shoulder scratches, and stress response of bred sows at mixing1

The objective of this study was to determine the effects of boar presence on aggression, shoulder scratches, and salivary cortisol in group-housed sows during the period after mixing, which is when dominance hierarchies are formed. A total of 225 York-shire sows were used. Five groups of 15 sows were each exposed to 1 of 3 levels of boar presence (n = 15): physical (boar in pen with sows; 2.15 m2 per sow), fenceline (boar housed adjacent to sows; 2.3 m2 per sow), or control (no boar in the room; 2.3 m2 per sow). The experiment was divided into 2 phases. In phase 1, behavioral measurements were taken for 48 h after mixing and boar introduction. In phase 2, behavioral measurements were taken beginning on d 6 after mixing and included 24 h before and 48 h after boar removal. In phases 1 and 2, shoulder scratches were scored 24 h before and 24 h after mixing and boar removal, respectively. Saliva samples were collected each morning (0600 to 0700) and afternoon (1600 to 1700) during both phases. Frequencies of intersow aggressive contact (bite, body knock, and head knock) and threats as well as frequencies and durations of fighting bouts were determined from video recordings during daily feeding (49.6 +/- 1.4 min) and nonfeeding (21 +/- 0.2 h) periods. During phase 1, boar presence did not affect the frequency of threats during either the feeding or nonfeeding periods. Control groups had fewer aggressive contacts at feeding during the 25- to 48-h period compared with the fenceline groups (P = 0.01). Total duration of fighting and average fighting bout duration were unaffected by treatment. However, the number of fights occurring during feeding 25 to 48 h postmixing was lower in the physical groups than in the fenceline groups (P = 0.023); measures for the control groups were intermediate. Physical sows also received fewer shoulder scratches postmixing than did control sows (P = 0.048). After mixing, physical sows showed greater morning (P = 0.08) and afternoon (6 h postmixing, P = 0.01; 32 h postmixing, P = 0.08) salivary cortisol concentrations compared with fenceline sows, although they were only numerically greater than those for control sows. During phase 2, removing the boar did not increase fighting among sows or affect shoulder scratches or salivary cortisol concentrations. The presence of a boar was minimally effective at reducing fighting and scratches during the postmixing period, and sows showed a greater stress response in the presence of a boar.

Search for the feeding-entrainable circadian oscillator: a complex proposition

working in the laboratory of John B. Watson in the early 1920s, Curt P. Richter first observed the phenomenon of rats engaged in what would later be called food-anticipatory activity: “It is seen that immediately following the daily feeding period there is a period of relative inactivity lasting

Utilization of dietary minerals and blood biochemical values in lambs fed hydrated sodium calcium alumino silicate sorbent material at supplementary level

An investigation was made in lambs to study the utilization of dry matter (DM), dietary minerals and changes in certain blood biochemical values due to the inclusion of hydrated sodium calcium alumino silicate (HSCAS) as a sorbent material in the concentrate mixture. Fourteen lambs of uniform age and body weights were allotted to two dietary groups, control ( T 1) and experimental group supplemented with 5 g kg −1 of HSCAS ( T 2). The feeding was continued for 105 days and the results indicated no variation in the intake of concentrate, hay and also the fortnightly body weight changes between the groups. Digestibility trial conducted showed that the dry matter (DM) consumption varied between 3.21 and 3.28% of their body weight and the ratio of concentrate and hay consumption was 37:63 ( T 1) and 36:64 ( T 2), respectively. The digestibility coefficient of DM between the groups varied non-significantly ( T 1: 0.541 ± 0.018; T 2: 0.576 ± 0.023). Though the intake of minerals studied was similar in both the groups, the apparent gut absorption coefficients of copper (Cu: 0.239 ± 0.028 and 0.107 ± 0.010), Zinc (Zn: 0.279 ± 0.024 and 0.213 ± 0.019), Iron (Fe: 0.175 ± 0.015 and 0.128 ± 0.055) and Manganese (Mn: 0.423 ± 0.028 and 0.356 ± 0.015) were significantly ( P < 0.01; 0.05) lower in lambs fed HSCAS. However the utilization of Calcium (Ca), Phosphorus (P) and Magnesium (Mg) did not differ. Analysis of blood plasma at 0, 50 and 100 days of feeding period for total protein, albumin, globulin and urea did not show any significant variation due to HSCAS feeding. It is concluded that inclusion of HSCAS at 5 g kg −1 concentrate mixture resulted in lower absorption of certain trace minerals (Cu, Zn, Fe, Mn) and thus it is required to additionally supplement these minerals in diet when such sorbent material is used.

Effect of Dietary Feeding Regimens on Urea and Protein Concentration of Milk in Murrah Buffaloes

The present study was planned to examine the effect of different feeding regimens on milk urea concentration and milk protein concentration. The objectives are to describe the diurnal variations of milk urea (MU) concentration and to predict plasma urea (PU) concentration from MU concentration. Six lactating Murrah buffaloes were distributed in two groups and were fed two different diets in a crossover design. The diets consisted of leguminous crops as diet 1 (berseem (Trifolium alexandrinum)+concentrate mixture 1+wheat straw)) and non-leguminous crops as diet 2 (oats (Avana sativa)+concentrate mixture 2+wheat straw). All the diets were isocaloric and isonitrogenous. Each diet was fed to the animals for a period of 28 days, followed by a 10 day gap to obviate the carry over effect of the previous diet and then a switch over to the other diet. Digestibility trials were conducted on the last 7 days of each feeding period. Milk samples were collected on day 3, 7, 10, 14, 17, 21, 24 and 28 of the feeding period and blood samples were collected on the same day at morning within 30 minutes after morning milking. The average milk urea (MU) values (mg/dl) differed significantly (p<0.01) and were 44.83±0.62 and 42.53±0.73, respectively, for diets 1 and 2. Milk urea concentrations (mg/dl) also varied (p 0.01) among the days of feeding period, but were stabilized after 10th day of feeding period. In contrast, diets and days of feeding period had no significant effect on percent milk protein. Plasma urea concentration showed a significant (p<0.01) positive correlation (r = 0.93) with MU concentration. To predict the from MU the following equation was developed PU = 10.67±0.76×MU (mg/dl) with R 2 = 0.87. A clear diurnal variation of MU was found with lowered morning value (42.04±0.68 mg/dl) than the evening value (45.32±0.66 mg/dl). Present findings suggested that MU or concentration could be used as an indicator to monitor the feeding strategy. Plasma urea can be predicted from MU, whenever interpretation of milk urea data required consideration of diurnal variation. (Asian-Aust. J. Anim. Sci. 2005. Vol 18, No. 7 : 973-979)

Laboratory and field assessment of uranium trophic transfer efficiency in the crayfish Orconectes limosus fed the bivalve C. fluminea

At present, ecotoxicological information regarding the impact of natural uranium (U) on freshwater ecosystems via the trophic contamination route is scarce. We generated an experimental trophic food chain involving the prey species, Corbicula fluminea, and a predator, Orconectes limosus, for a 10-day and a 30-day feeding periods (food ration: one whole soft body/day/crayfish). We studied the efficiency of U trophic transfer and the distribution of U in the predator. During the test, we varied the quantity of dietary U (from beforehand contaminated bivalves at concentrations ranging from 0.9 ± 0.1 to 20.2 ± 9 μg/g fw provided to each crayfish over the 10 days) applying a daily feeding rate equal to 3.9 ± 0.8% fw. The efficiency of U trophic transfer from clams to crayfish varied between 1 and 13% depending on the prey exposure modalities. Accumulation of U was observed in the digestive gland but also in gills, in the muscle, and in the molt of the crayfish after trophic exposure treatments. Under high-level exposure conditions, the digestive gland was the main target-organ, however a significant accumulation was also observed in the stomach. With regard to low levels of trophic exposure, accumulation of U in gills, in the stomach, and in the digestive gland was of the same order of magnitude. Longer exposure period which incorporated a crayfish molt, resulted in a decrease of trophic transfer ratio and a modified U tissue distribution.

Phenotypic variations between a fat‐preferring strain and a macronutrient non‐preferring strain of mouse

This study aims to establish a model that will allow the comparison of the phenotypic variations between a fat-preferring strain and a macronutrient non-preferring strain of mouse. Five strains (AKR, A/J, ARC, C57Bl/6 and BALB/c) were fed a two-choice diet (high-fat/low-carbohydrate and low-fat/high-carbohydrate) for 30 days. Following completion of the 30-day feeding period, the brains of the fat-preferring and macronutrient non-preferring mice were removed for the analysis of the expression of the genes - agouti-related peptide (AgRP) and pro-opiomelanocortin (POMC). Upon completion of the experiment, it was found that the C57Bl/6 strain was the strongest fat preferrer consuming 72% of their calories from the high-fat diet, whereas the BALB/c was found to have no macronutrient preference. Using in situ hybridization techniques, no significant differences in the expression of POMC were found between the two strains. It was, however, showed that the BALB/c mice had a 33.7% higher expression level of AgRP than the C57Bl/6 mice. The lower expression level of AgRP in the C57Bl/6 mice may be suggestive of a defensive response to their chronic preferential consumption of the high-fat diet. However, the wide variety of neuroregulatory signals involved in macronutrient preference along with the possibility of the occurrence of post-transcriptional effects suggests further biological analyses need to be performed using this model.

Effect of sampling interval and temperature on the accuracy of food consumption estimates from stomach contents

The effect of temperature and sampling interval on the accuracy of food consumption estimates based on stomach contents was studied using simulation. Three temporal patterns of feeding were considered (scattered throughout the day, one 5 h period or two 5 h periods) and gastric evacuation was modelled according to published values. Sampling intervals of 3 h gave reasonable food consumption estimates (2 to 19% error) at all temperatures. Comparably, sampling intervals as large as 12 h gave reasonable estimates of food consumption (1 to 20% error) when temperature was set to ≤10° C. At temperatures &lt;5° C, even 24 h intervals (equivalent to one daily sampling) provided reasonable estimates of daily food consumption (2 to 19% error) for all but the highest gastric evacuation rate combined with one daily feeding period (47% error). The temperature effect on estimation error resulted from diminishing temporal fluctuations in stomach contents with slower gastric evacuation rates. It follows that sampling effort may be considerably minimized when estimating food consumption from stomach contents during periods with low temperatures such as the winter time experienced by temperate fishes.

Food Habits, Daily Ration and Relative Food Consumption in Some Fish Populations in Ubolratana Reservoir, Thailand

The diet composition and feeding habits have been investigated for several economically important indigenous species based on diel surveys collected from the Ubolratana reservoir (Thailand). For some of these populations the daily food ration, feeding periods, ingestion and evacuation rates were determined using MAXIMS, an iterative computer software utilising 24-hour series of stomach content data obtained in natural populations. The results obtained provide useful information for studies of the trophic relationship in the reservoir and can be explained by some observed migrating patterns of these fish populations.

In situ growth and mortality of mesozooplankton during the austral fall and winter in Marguerite Bay and its vicinity

Abstract Zooplankton play a critical role in the austral winter ecosystem of the Southern Ocean, transporting biomass from lower to higher trophic level organisms through their consumption and growth, and ultimately determining the survival of marine animals such as sea birds and mammals. Previous studies have provided evidence that krill utilize zooplankton through austral winter when the primary production is negligible. Though they are different, all survival strategies produce the same result, a decrease in total zooplankton biomass. It is difficult to examine the total zooplankton biomass balance and process rates from traditional net tow samples because of the spatial variation in zooplankton distribution and the lack of applicable mathematical methods to estimate population process rates. This study focuses on short-term (overnight) loss rates of mesozooplankton associated with adult krill grazing in austral fall and the long-term (winter) body growth and removal rates of mesozooplankton in austral winter based on measurements of zooplankton size structures obtained using an Optical Plankton Counter (OPC) mounted on a Multiple Opening and Closing Nets and Environmental Sensing System (MOCNESS). In order to target an adult Euphausia superba aggregation for a short period, a 153 kHz Vessel-Mounted (VM) Acoustic Doppler Current Profiler (ADCP) was used for the acoustic backscattering. The in situ process rates of growth and mortality are estimated based on the biomass balance and biomass spectrum theory. The overnight in situ grazing by adult E. superba on mesozooplankton is examined based on the in situ measurements of mesozooplankton biovolume within the water where an adult E. superba aggregation remained during a short study period in late April. The measurements show that approximately 16% of the existing mesozooplankton biovolume was removed in 4 h, which leads to an average specific daily grazing rate of 0.96 day - 1 assuming a daily feeding period of 16 h from dusk to dawn. From the amount of biovolume removed and the abundance of adult euphausiids of approximately 3 individuals m - 3 estimated from the volume backscattering strength and the size of adult euphausiids, the daily ration for an adult euphausiid is approximately equal to 7% body biovolume or biomass day - 1 . The total mesozooplankton biovolume decreased at a specific rate of 0.017 day - 1 over the austral winter 2002, while the specific individual body growth was approximately 0.045 day - 1 . The sum of these two rates leads to the specific mortality rate equal to approximately 0.07 day - 1 for the winter. These rates lead to a system efficiency of 67% for recycling the biomass during the winter. The measurements indicate that approximately 90% of biovolume (biomass) was removed in the period between the fall cruise in April–May and the winter cruise in August–September 2002.

Prebiotics and immune responses.

Feeding breast milk of healthy mothers is associated with a lower incidence of infectious and allergic diseases. Although this effect is of multifactorial origin, it is widely accepted that the entire intestinal flora of breastfed infants provides anti-infective properties and is an important stimulating factor for the postnatal development of the immune system. Clearly, the effect of human milk on the postnatal development of the intestinal flora cannot be attributed to a single ingredient. It is generally accepted, however, that human milk oligosaccharides play a key role in this matter (1). The composition of human milk oligosaccharides is very complex. As they are resistant against digestion, they can be detected in the faeces as well as in the urine of breast-fed infants (2). This low or absent digestibility is a prerequisite for prebiotic activities of dietary compounds (3). Apart from their prebiotic effects, there is also evidence that human milk oligosaccharides act as receptor analogues to inhibit the adhesion of pathogens on the epithelial surface (1) and interact directly with immune cells (Eiwegger Th, et al., unpublished data). Due to their complexity, oligosaccharides with structures indentical with human milk oligosaccharides are not available as dietary ingredients. Searching for alternatives, a mixture of neutral galacto-oligosaccharides (GOS) and fructo-oligosaccharides (FOS) have been identified as effective prebiotic ingredients during infancy (5). More recently, also acidic oligosaccharides such as pectin hydrolysate are under investigation (6). In several clinical trials it could be demonstrated that feeding a formula supplemented with a mixture of GOS and long-chain FOS results in an entire intestinal flora similar to that found in breast fed infants (7). Comparable to human milk oligosaccharides, GOS and FOS stay present during the whole gastrointestinal passage and are therefore detectable in the faeces of infants fed a GOS/FOS supplemented formula. With regard to stool characteristics, there was a significant influence of GOS/FOS in preterm as well as term infants: feeding the oligosaccharides-supplemented formula increased the stool frequency and softened the stool consistency in comparison to a standard formula so that stool characteristics could be achieved which were very similar to those of human milk fed infants (5). In a study in term infants the effect of different concentrations of the GOS/FOS mixture was tested in parallel by a traditional plating technique and a modern molecular biologic technique (7). Whereas with the plating technique, only living bacteria can be detected, all bacteria are counted with the molecular biologic technique. The results obtained by the two methods are shown in Figure 1. They clearly indicate that with the use of the GOS/FOS mixture, the number of bifidobacteria increases and the effect is much more pronounced for the living bacteria than for the total number of bacteria. Short-chain fatty acids (SCFA) are an important marker of the bacterial metabolism in the intestine. Invitro experiments focusing on the short SCFA synthesis by the faecal flora could demonstrate that the SCFA synthesis from GOS/FOS mixture was comparable to the synthesis from a quantitatively equivalent neutral human milk oligosaccharides fraction (7). Similar results were obtained in-vivo by measuring the fatty acid pattern in faeces from infants fed a formula supplemented with GOS/FOS: The faecal SCFA pattern was similar to that observed in breast fed infants (8). The results are in line with the observation that during a 28-day feeding period the faecal pH decreased in a group of term infants fed a GOS/FOS supplemented formula similar to breast fed infants, whereas the faecal pH in infants fed a nonsupplemented standard formula increased (5). Increased numbers of bifidobacteria and a decreased faecal pH are contributing to a reduction of clinically relevant pathogens, either expressed in absolute numbers or as percentage of total bacteria. In an animal study using the mouse vaccination model as recommended by international governmental guidelines (6), feeding GOS/FOS significantly stimulated the cellular (i.e., Th1/Th2) immune balance. In an animal model for allergic hypersensitivity using ovalbumin as allergen, dietary GOS/FOS inhibited the allergic inflammation (7). In summary, the data demonstrate that an infant formula supplemented with a mixture of GOS/FOS stimulates the entire intestinal flora and results in the production of physiologically important bacterial metabolites as well as a faecal pH similar to influences of human milk feeding. These effects are accompanied by stool characteristics close to those of breast-fed infants and by a Address correspondence and reprint requests to Prof. Gunther Boehm, Director Infant Nutrition Research Germany, Milupa GmbH & Co, KG Bahnstrasse 14-30, D-61381 Friedrichsdorf; Fax: 0049-6172991862 (e-mail: guenther.bohem@milupa.de). Journal of Pediatric Gastroenterology and Nutrition 39:S772–S773 © June 2004 Lippincott Williams & Wilkins, Philadelphia

Feeding ecology of dunlins Calidris alpina staging in the southern Baltic Sea, 1. Habitat use and food selection

The feeding habits of migrating dunlins Calidris alpina staging in different non-tidal coastal habitats in the southern Baltic Sea are described. The study also focuses on the structure of the benthic macrofauna of these habitats and the diet choice of dunlins. All investigations were carried out on Langenwerder Island (Wismar Bay), where different types of flats and beaches harbour a total of 30 to 40 species of marine macrofauna. The composition of the macrobenthos differed considerably between the eulittoral sandbank, the eulittoral mudflat, the pebble beach, and the sublittoral surroundings. Most dunlins were observed foraging in flocks of up to several hundred individuals on the eulittoral flats. Densities of up to 20 to 30 foraging dunlins ha −1 occurred annually during peak migration in September and October. Macrobenthos biomass in these habitats fluctuated between 20 and 40 g AFDM m −2. The mean total food consumption of dunlins during autumn migration was estimated at 0.01 g AFDM m −2 d −1. The predation pressure could be estimated at 3 to 6% of the suitable food supply. Dunlins staging on Langenwerder were able to attain a pre-migratory mass gain of 0.2 to 0.5% of their body weight per day within an 8 to 12-h daily feeding period. The birds fed predominantly on the polychaete Hediste diversicolor by probing. They selected small 7 to 31-mm-long individuals. When water levels were high, and the eulittoral flats inundated, many dunlins switched to foraging along the shorelines where a variety of small prey were taken from spilled macrophytes. Dunlins sometimes obviously ignored their most important food H. diversicolor, although available, by feeding on other prey such as juvenile fishes and shrimps, dipteran larvae or spilled amphipods. When feeding on amphipods, dunlins selected the smallest individuals.

Behavioral, nutritional, and toxicological responses of cattle to ensiled leafy spurge.

Yearling cattle (n = 25; 416.1 +/- 25.9 kg) were stratified by weight and gender across five groups. Group 1 (OAT) was offered oat/rape haylage (ORH) for ad libitum consumption during two daily feeding periods. Group 2 (SPURGE) was offered leafy spurge/grass haylage (LSGH) for ad libitum consumption during the same feeding periods. Group 3 was offered ORH in an amount equal to the average amount of LSGH consumed by SPURGE at the previous feeding. Group 4 (MIX) was offered LSGH mixed with ORH for ad libitum consumption during the two feeding periods. Group 5 (PAIR) received the equivalent amount of ORH consumed by MIX at the previous feeding. The DMI for OAT, SPURGE, and MIX were similar at the first feeding (P = .52). The SPURGE group consumed very little LSGH thereafter and was removed from the trial. The OAT and MIX groups consumed similar amounts of DM daily on d 1 to 4 when the ration offered to MIX was only 7% LSGH (P = .33). When LSGH made up > or = 21% of the mixture (d 7 to 32), the OAT group consumed more daily DM than did MIX (P < .05). The spurge/oatlage ration offered to MIX was less digestible than the oatlage-only ration offered to PAIR (P < or = .01). Even though blood chemistry did not indicate that LSGH consumption caused organ damage, its intake caused minor alterations (P < or = .05) in serum albumin, calcium, gamma glutamyltransferase, P, K, and urea nitrogen. No gross or microscopic lesions, infectious agents, or significant numbers of parasites were detected in any of the carcasses or tissues examined. The MIX group had diarrhea for much of the trial. In Trial 2, five yearling cattle were adapted to a mixture of 21% LSGH and 79% ORH. Then they were simultaneously offered three mixtures of spurge and oat haylages: 1) spurge ensiled with a microbial inoculant (LSGH); 2) spurge ensiled with the same inoculant and a cellulolytic/hemicellulolytic enzyme (ENZ); and 3) spurge ensiled with the same inoculant and molasses (MOL). The mixture with ENZ was preferred over those with MOL or LSGH (P < .001), but the amounts consumed were low and similar to those for LSGH-ORH in Trial 1 when amounts of ENZ and LSGH in the mixtures were similar. The ENZ mixture may have been more palatable than LSGH and MOL because it had less (P < .05) lactic acid, but intake of ENZ indicates that it had aversive characteristics, like LSGH. Ensiling leafy spurge did little, if anything, to improve its palatability to cattle.

Feeding and Growth of Japanese Quail (Coturnix C. Japonica) Chicks With Unpredictable Food Access

We investigated the effect of unpredictable feeding times on feeding activity and body mass gain in fast growing Japanese quail (Cotumix c. japonica) from 7 to 31 d of age. Quail chicks were subjected to a long day length (18L:6D) with ad libitum food during (1) 17.5 h of the light period, starting 0.5 h after lights-on (group A, n = 14), (2) 6 h of the light period, starting 0.5 h after lights-on (group B, n = 14), and (3) 6 h of the light period, starting pseudorandomly either 0.5, 6, or 11.5 h after lights-on (group C, n = 12). We examined the effects on locomotor, feeding and drinking activity, body mass, and food intake. Treatment did not affect daily locomotor, feeding, or drinking activity. Distribution of activity over the light period was affected: group B and C showed more activity above the feeder and water container outside the feeding time, and showed a large bout of locomotor and feeding activity at the start of this period. Both overall weight gain and gross energy intake (GEI) were highest in group A and lowest in group C. Distribution of food intake throughout the daily feeding period was affected: group B and C consumed more food during the first part of the feeding period than group A. Daily GEI in group C was influenced by fasting duration prior to feeding and by time of food availability. We suggest that young quail adjust their feeding behaviour in response to their instantaneous energy needs. This effect is modulated by time of food availability: food arriving later in the day led to higher intake levels.

Influence of Ethanol Consumption on Immune Competence of Adult Animals Exposed to Ethanol In Utero

Ethanol consumption results in significant changes in the immune system of experimental animals and humans. Previous work by ourselves and others has established that in utero exposure to ethanol results in alterations in the immune system of the offspring that persist into adult life. The present study was designed to determine if prenatal exposure to ethanol results in increased vulnerability to the immunosuppressive effects of ethanol consumption in adulthood. Male and female Sprague-Dawley offspring were selected in adulthood from prenatal ethanol (E), pair-fed (PF), and ad libitum-fed control (C) groups, and given either an ethanol-containing liquid diet or were pair-fed an isocaloric liquid diet without ethanol for 30 days. At the end of the 30-day feeding period, lymphocyte responses to the mitogens concanavalin A (Con A) and lipopolysaccharide, and to interleukin-2 (IL-2) were tested using in vitro assays. The results of this study support and extend previous data demonstrating long-term adverse effects of prenatal ethanol exposure on T-cell responses to mitogens, and provide further evidence that deficits seem to be more robust in male than in female offspring. Prenatal E males showed reduced T-lymphocyte proliferation to Con A and T-lymphoblast proliferation to IL-2, compared with their prenatal PF and C counterparts, regardless of whether they were exposed to the ethanol or the control diet in adulthood. In addition, T-lymphoblast proliferation to IL-2 was suppressed in prenatal E, compared with prenatal C, females exposed to control diet in adulthood. This is the first report of a deficit in T-cell aspects of immunity in E females, although it appears that this deficit may have been partially mediated by nutritional effects. A second major finding in this study is that consumption of ethanol diet in adulthood in itself had significant immunosuppressive effects on T-cell responses in both males and females. However, contrary to our expectation, previous exposure to ethanol in utero did not exacerbate the changes in immune responsiveness that were observed after adult ethanol consumption.