Weeks Of Experimental Feeding Research Articles

Histomorphometric evaluation of melanomacrophage centers (MMCs) and CD3+ T cells of two morphs of brown trout (Salmo trutta) fed diets with immunostimulants

The brown trout (Salmo trutta) is a salmonid residing in riverine and coastal waters throughout the Northern Hemisphere, whose various populations evolved into distinct ecological morphs, differing in their migratory tendencies and preferred habitats. Unfortunately, due to progressing degradation of natural environment, the conservation of these populations is of growing importance and is undoubtedly a challenging task. Therefore, various means to refine the preparatory protocols for restocking using hatchery-reared fish are being pursued, some of which involve the administration of immunity-boosting substances. The current study assessed the effects of two dietary immunostimulants: Bioimmuno (4% inosine pranobex and 96% β-glucan) and Focus Plus (commercial preparation by Biomar, Denmark) on two morphs of the brown trout – the river trout (S. trutta morpha fario) and the sea trout (S. trutta morpha trutta). Tissue samples were obtained from ∼75 to 100g fish after 0, 2 and 4 weeks of experimental feeding. Multi-factorial analysis of conducted histological measurements of melanomacrophage centers (MMCs) revealed no changes of their parameters within spleens, but showed a decrease of the occupied tissue area and MMC counts in the livers, progressing with time regardless of the applied diet. Immunohistochemical analysis of CD3+ T cells showed their increased recruitment into mucosal folds of pyloric caeca in the 2-week sampling of trouts fed with the diet with 2% Bioimmuno addition, but this effect was not present in the 4-week sampling. When studying all groups jointly within each morph, there was a significant difference in terms of maintained CD3+ T cells levels, as sea trouts showed significantly higher tissue areas occupied by these cells than river trouts, both in the pyloric caeca and hepatic parenchyma. The study revealed that feeding with a diet enriched with Bioimmuno for 2 weeks may be a favorable enhancement of rearing protocols of brown trout stocks prior to their release, but more studies need to be conducted to test the possibility of an even shorter feeding period.

Feed Preference, Daily Intake, and Laying Performance of Captive-Born Sardinian Partridges (Alectoris barbara barbara Bonnaterre, 1790) Offered Whole Defrosted Mealworms (Tenebrio molitor L., 1758) as Raw Feed Material with Diet

The competence to locate natural feeding sources is one of the main limiting factors for survival in the wild, especially for captive-born birds. Therefore, environmental enrichment through the diet can be strategic before their release into nature. In this research, a feeding trial was undertaken to evaluate the potential use of yellow mealworm (Tenebrio molitor L.) larvae (TM) provisions to captive bred couples of Sardinian partridges (Alectoris barbarabarbara Bonaterre, 1790) during the laying period. Twenty-four couple-caged Sardinian breeding partridges were enrolled during the laying period (April–May 2019) and randomly allotted to two feeding groups of 12 couples each: (a) the control (CON) group was fed a conventional complete pelleted diet for laying quails; (b) the yellow mealworm enriched group was additionally fed 5% whole, defrosted TM larvae (TM5%) on top of the same amount of the control diet. As a prerequisite, partridges were unaccustomed to eating mealworms before the start of the trial. Daily feed intake (DFI), bodyweight (BW), and number of laid eggs (LE) were monitored over five weeks of experimental feeding. Partridges fed the TM5% diet displayed a higher preference for whole mealworms (first choice and complete consumption) than expressed for the CON pelleted feed. Differences in daily dry matter intake (p = 0.028) between CON and TM5% groups were observed (DMI: 42.6 ± 1.73 vs. 43.4 ± 1.62 g, respectively); the final body weights (BW) (p = 0.098) of birds in the CON group was higher than those in the TM5% group (435 ± 36.9 vs. 416 ± 36.3 g, respectively). Differences in daily energy intake relative to BW (p < 0.001) as well as relative to metabolic weight (BW0.75) (p < 0.001) were observed between groups, but this was not followed by higher BW, probably due to the absence of grit and inaccessible nutrients and energy (larval exoskeleton). No difference in the average LE per week and egg weight was observed between CON and the enriched TM5% groups, though in the last weeks, a statistically lower number of eggs was laid in TM5% group. Our results suggest that whole yellow mealworms can be a promising feed material to broaden the spectrum of competence for natural feeding sources with similar physical form and nutritional characteristics available in the environment.

A potential new biomarker to monitor the phosphorus balance in dry dairy cows

The present study aimed at comparing different candidate blood biomarkers in their suitability to determine activation of regulatory mechanisms responding to phosphorus (P) deprivation in dry dairy cows on deficient dietary P supply. Fifteen multiparous dairy cows in late pregnancy were assigned to either a diet with low (1.6 g/kg DM) or adequate P content (3.5 g/kg DM) during the last 4 weeks of gestation. Blood samples were obtained immediately prior to initiating the experimental feeding period (T-bl), after 2 weeks of experimental feeding (T-1) and 4 days before calving, which was equivalent to at least 3 weeks of experimental feeding (T-2). Studied parameters were the plasma concentrations of phosphate (Pi), calcium (Ca), CrossLaps (CTX), a biomarker for bone mobilization, 1,25-(OH)2-Vitamin D (1,25-(OH)2D) and the activity of alkaline phosphatase (AlP). Treatment and time effects were studied with repeated measures ANOVA, and the different parameters were correlated to the dietary P intake in the days before sampling. Treatment effects were only identified for the individual increase in the plasma concentration of CTX related to baseline values (ΔCTX) and to a lesser extent for the Ca:Pi ratio in plasma. ΔCTX was the only parameter correlated to P intake at T-1 and with the strongest association with P intake at T-2. The results of this study provide first indications for the suitability of ΔCTX to determine the level of dietary P supply at which counter regulatory mechanism to negative P balance are triggered during the dry period. This parameter that is easily applicable in a field setting can assist the validation of current recommendations for the dietary P supply in dry cows.

Effects of riboflavin supplementation level on health, performance, and fertility of organic broiler parent stock and their chicks

Data from breeder hens and chicks are particularly critical for the development of vitamin B2 recommendations for organic poultry. To test safe thresholds of supplementation, 100 breeder hens (Hubbard JA 57 K) and ten cockerels were allocated to ten housing groups, with each receiving supplementation of either 4.0 (treatment CON) or 2.5 mg (treatment RED) riboflavin per kg feed. After 15 weeks of experimental feeding, 256 eggs were incubated. From the hatched chicks (Hubbard S757), 192 were allocated to four treatments based on their parents’ treatment (CON- or RED-) and on their own supplementation of either 4.0 (-CON) or 2.5 mg (-RED) riboflavin per kg feed. Two groups of each combination (CON-CON, CON-RED, RED-CON, RED-RED), each with 24 chicks of both sexes, were fattened for nine weeks and slaughtered. Analysis of total riboflavin (sum of native concentrations and supplements) in the parent’s feeds revealed an average, over the 15 weeks, of 7.8 and 5.8 mg per kg feed for CON and RED, respectively. Body weight, plumage integrity, gait appearance, footpad, claw and keel bone integrity, lesion scores, laying performance, and egg mass were found to be of similarly high levels for all hens without any treatment effects. Performance traits of the hens in both treatments reached the specifications of the producer for this genotype. Yolk and albumen riboflavin concentrations were not affected although yolk colour in the RED treatment group became darker. Fertility was not affected, and hatchability was 100 per cent. Total riboflavin concentrations in the broiler diets were on average, over 9 weeks, 8.2 and 6.1 mg/kg for CON and RED, respectively. In chicks, RED treatment of their parents led to significant depressions of feed intake and growth. The RED treatment of the chicks themselves also impaired growth. Growth rates of the CON-CON treatment were in line with the specifications of the producer for this genotype. Plumage scores, footpad integrity and walking appearance of the broilers, and dressing percentage of the carcasses were not affected by treatment. The RED treatment of chicks caused lower spleen and heart weights, while pancreas and liver weights, and liver riboflavin concentrations were not affected. In conclusion, supplementation of 4.0 mg/kg to organic diets did not evoke any health or performance problems for breeder hens or broiler chicks, while a supplementation level of 2.5 mg per kg feed led to reduced weight gains, although without any other riboflavin deficiency symptoms.

The effect of Thymbra spicata hydroalcoholic extract loaded on chitosan polymeric nanoparticles on some growth performances, hematology, immunity, and response to acute stress in rainbow trout (Oncorhynchus mykiss)

This study aimed to optimize the performance of Thymbra spicata (TS) plant extract using chitosan polymeric nanoparticles (CNPs) on growth parameters, blood, immunity, and response to acute stress in rainbow trout (Oncorhynchus mykiss). TS extract-containing nanoparticles (TSCNPs) were prepared by the ion gelation method. Juvenile rainbow trout (n = 750; 30.21 ± 3.04 g) were randomly divided into 10 treatments, including an extract- nanoparticle-free control and treatments with 100, 200, 400, and 800 mg/kg diet of TS extract with and without CNPs, and one treatment with 2.5 g/kg diet of CNPs, each with three replications. After 8 weeks of experimental feeding, final weight, weight gain, feed efficiency, protein efficiency ratio, and feed conversion ratio were significantly improved in the groups fed with 200 and 400 mg/kg diet of TSCNPs compared to the other groups (P < 0.05). Carcass composition contained significantly more protein and less fat in treatments fed with TSCNPs than the other treatments (P < 0.05). Red blood cells, hemoglobin, hematocrit, white blood cells, lysozyme, ACH50, immunoglobulin, total protein, albumin, and globulin were higher in the treatment fed with 400 mg/kg diet of TSCNPs than the other groups (P < 0.05). Post-stress levels of cortisol, glucose, and lactate increased in all treatments, but the lowest levels of these parameters after 480 min of stress were observed in the treatment with 400 mg/kg diet of TSCNPs. The findings show that the use of CNPs as carriers of TS improves the performance of the plant extract in growth, blood parameters, immunity, and stress response of rainbow trout.

Effect of herbal feed additives on intake, rumen fermentation, availability of nutrients and energetic efficiency of feeds in Barbari kids reared under confined condition

Weaned male Barbari kids (24) were divided equally into three groups (T1, T2 and T3) to investigate the effect of supplementation of herbal feed additives in the complete pelleted feed on intake of nutrients, rumen fermentation, availability of nutrients and energetic efficiency under stall-fed condition during an eight months feeding trial. Treatments were T1, Concentrate mixture (40%) plus arhar (Cajanus cajan) straw (60%) in Total Mixed Ration (TMR) form fed ad lib.; T2, Concentrate mixture (40%) plus arhar straw (60%) in Complete Feed Pellets form fed ad lib.; T3, Concentrate mixture (40%) plus arhar straw (60%) in Complete Feed Pellets form supplemented with herbal mixture (four herbs; Tulsi: Haldi: Amla: Arni, ratio 1:1:1:1 on DM basis) @ 0.5% in complete feed fed ad lib. Rumen fermentation pattern was studied at 3rd and 25th weeks of experimental feeding. A metabolism trial was conducted at the last phase of the experiment. During metabolism trial, DMI (g)/kg W0.75 and CPI (g)/kg W0.75 was greater in kids under T3 and T2 than T1. Pelleted complete feed supplemented with phytogenic feed additives resulted greater total VFA (mmol/dl SRL) concentration in rumen liquor of kids under T3 than TMR fed kids (T1) at three weeks of experimental feeding. The concentration of NH3-N (mg/dl SRL) was depressed significantly in T3 at 3rd and 25th weeks of feeding; T1 showed highest values during both periods. TDN intake (g)/kg W0.75 and Digestible Energy intake (MJ)/kg W0.75 were increased significantly in T3 and T2 than T1. DCP intake (g)/kg W0.75 was also higher in T2 and T3 than T1. Similarly, N-balance (g)/kg W0.75 increased significantly in T3 and T2 than T1. Therefore, it may be concluded that densification of feeds in the form of complete pelleted feed (T2) and further supplementation (@ 0.5% in the complete feed) with herbal mixture (Amla, Haldi, Arni and Tulsi=1:1:1:1 on DM basis) (T3) increased the intakes of DM, TDN, digestible energy and protein; enhanced rumen fermentation pattern, and increased N-balance in finisher Barbari kids.

Immunostimulatory Effect of Phoenix Dactylifera Supplemented Diet on Aeromonas hydrophila Infected Clarias gariepinus

Background: Phoenix dactylifera fruit has been widely reported for its effective anti-inflammatory properties. Therefore, the effect of P. dactylifera on immune responses was evaluated in Aeromonas hydrophila infected Clarias gariepinus. Methods: P. dactylifera fruit powder was used as feed inclusion at 0 (control), 0.5, 1.0 and 2.0% concentrations to the pelleted fish diet of C. gariepinus juveniles. A total of 75 fish were divided into fourgroups (n=15) . The fish were fed with the formulated feed twice a day (08:00 h and 17:00 h), and terminated 24 h before the commencement of the microbial inoculation with inactivated Aeromonas hydrophila bacteria. The fish were later challenged with active Aeromonas hydrophila after seven weeks of experimental feeding. Blood samples were collected from fish while haemagglutination and phagocytic assays were used to determine the antibody titres and phagocytic action of the immune cells, respectively. Then, the micronucleus assay was used to determine the chromosomal damage effect of Aeromonas hydrophila pathogen on exposed C. gariepinus. Results: After the challenge, the groups fed with 0.5 and 2.0% date showed significantly (p˂0.05)elevated level of immune responses with antibody titres of 231.49±77.06 and 257.18±51.37, and phagocytic activity values of 0.07±0.01 and 0.04±0.00, respectively. The clastogenic effect of A. hydrophilaon the peripheral blood of infected C. gariepinus was observed, this was significantly reduced in 2% P. dactylifera fed group. Also, increase white blood cell count was observed in the C. gariepinus group fed with 0.5% date supplement. A higher lymphoid organ index was also observed in fish fed with the supplemented diet, as compared to the control. Conclusions: These results indicate that P. dactylifera fruit powder enriched diet showed an immune-boosting and reduction of the DNA damaging effect in bacteria-infected C. gariepinus

Effect of Different Levels of Copper Nanoparticles and Copper Sulfate on Morphometric Indices, Antioxidant Status and Mineral Digestibility in the Small Intestine of Turkeys

Abstract It was hypothesized that dietary copper (Cu) nanoparticles, as a substitute for the commonly used copper sulfate, could contribute to lowering the dietary inclusion levels of Cu without compromising growth performance or reducing Cu digestibility and utilization in turkeys. An experiment was carried out on 648 one-day-old Hybrid Converter turkeys divided into 6 groups with 6 replicates per group in a two-factorial design with 3 dietary inclusion levels of Cu (20, 10 and 2 mg kg−1) and 2 dietary sources of Cu, copper sulfate and Cu nanoparticles (Cu-SUL and Cu-NPs, respectively). The apparent digestibility coefficients of minerals were determined after 6 weeks, and tissue samples were collected after 14 weeks of experimental feeding. A decrease in the dietary inclusion levels of Cu from 20 to 10 and 2 mg kg−1 did not reduce the body weights of turkeys at 42 and 98 days of age. In comparison with the remaining treatments, the lowest dietary inclusion level of Cu significantly decreased MDA concentrations in small intestinal tissue (P=0.002) and in the bursa of Fabricius (P=0.001). The replacement of Cu-SUL with Cu-NPs differentially modulated the redox status of selected tissues, i.e., enhanced SOD activity in small intestinal tissue (P=0.001) and decreased total glutathione levels in the bursa of Fabricius (P=0.005). In general, neither the different levels nor sources of additional dietary Cu (main factors) exerted negative effects on the histological structure of the duodenum and jejunum in turkeys. The intestinal digestibility of Cu increased with decreasing dietary Cu levels, and as a consequence, the highest apparent digestibility coefficient of Cu (and zinc) was noted in turkeys fed diets with the addition of 2 mg kg−1 Cu-NPs. Therefore, the environmental burden of excreted Cu was substantially reduced along with decreasing dietary Cu levels but it did not depend on the Cu source.

Effects of native or partially defatted hemp seeds on hindgut function, antioxidant status and lipid metabolism in diet-induced obese rats

The aim was to compare the effects of a small amount of native and partially defatted hemp seeds on hindgut function, antioxidant status and lipid metabolism in rats fed a high-fat (HF) diet. After 8 weeks of experimental feeding, HF dietary feeding induced obesity and a series of metabolic disorders in rats. Supplementation of the HF diet with both seed forms increased the cecal SCFA concentrations and improved the antioxidant status of rats, especially glutathione metabolism in the liver. Dietary consumption of the defatted seeds decreased liver triglyceride accumulation, whereas it unfavorably increased the liver cholesterol content. By contrast, dietary consumption of the native seeds decreased the plasma cholesterol concentration, especially the non-HDL fraction, and increased hepatic expression of PPARγ. This study demonstrates that low and regular consumption of both seed forms attenuates disorders associated with an unbalanced diet, although their consumption is unable to prevent the development of obesity itself.

Effects of dietary Sargassum horneri on resisting hypoxia stress, which changes blood biochemistry, antioxidant status, and hepatic HSP mRNA expressions of juvenile black sea bream Acanthopagrus schlegelii

Aquatic hypoxia is a frequent event and a complex set of physiological and biochemical alterations are employed to cope with this environmental stress in fish. This study aimed at evaluating the protective effects of Sargassum horneri on hypoxia stress in black sea bream Acanthopagrus schlegelii. Four hundred and eighty fingerlings with approximate mean body weight of 12.0 ± 0.1 g were randomly distributed into four experimental groups in triplicate. Each group was stocked with 40 fish and fed with isonitrogenous (42% crude protein) and isolipidic (12% crude lipid) experimental diets containing either 0% (control), 3%, 6%, or 9% S. horneri in the feed. At the end of 8 weeks of experimental feeding, fish were exposed to hypoxia (dissolved oxygen 2.5 mg L−1) conditions for 12 h and subsequent recovery to normoxia (dissolved oxygen 7.2 mg L−1). Fish samples were collected after hypoxia stress at 0, 6, 12 h, and 12 h recovery to normoxia, respectively. Hypoxia stress caused a significant increase in the serum concentrations of cortisol, glucose, and lactate at 6 h after hypoxia, as well as the activities of hepatic superoxide dismutase (SOD) and MDA content at 12 h after hypoxia compared with 0 h after hypoxia. Moreover, the fish exhibited a significantly higher level in the mRNA expressions of hepatic Cu/Zn-SOD, HSP70, and HSP90 at 12 h after hypoxia. However, dietary S. horneri supplementation could significantly improve antioxidant capacity and resistance against hypoxia stress, particularly in the 6% S. horneri group. Therefore, the optimal dietary S. horneri level based on increasing the resistance of hypoxia for juvenile black sea bream in the present study was estimated to be approximately 6% dry diet.

Subluminal Focal Lesions in Peyer's Patches in the Terminal Ileum of Pigs Fed With Different Physical Forms of One Same Diet.

Retrograde backflow of cecum chyme and consequent ascendent colonization of the foregut may occur via the ileocecal valve (IV) under predisposing circumstances. The Peyer's patches (PPs) in the terminal ileum (TI) play a crucial role in targeting antigens and act as a first line of blockage of pathogens in the small intestine. In view of the established impact of the physical form of the diet (grinding and compaction of ingredients) on the physicochemical and microbiological composition of digesta throughout the different gastrointestinal tracts, special attention was paid to PP reaction following different dietary treatments. The aim of this study was to explore the effect of different physical forms of one diet (identical for botanical and chemical composition) administered to growing pigs on macro- and microscopic morphology of PPs in the last 3 cm of the TI, as a region of interest immediately close to the IV involved in the prevention of retrograde contamination of the small intestine. The diet effect was tested after 4 weeks of experimental feeding on PPs of 32 growing pigs, fed with four dietary treatments differing for the physical form: FP—finely ground pelleted diet (dMEAN, 0.463 mm); CM—coarsely ground meal diet (dMEAN, 0.880 mm); CP—coarsely ground pelleted diet (dMEAN, 0.836); and CE—coarsely ground extruded diet (dMEAN, 0.659). A higher prevalence of subluminal focal liquefactive necrosis (FLN) in the last 3 cm of the TI was observed in pigs fed with the CE and the FP diet (n. 3/8 or 37.5% and n. = 1/8 or 12.5%, respectively) (p = 0.076). FLN negatively and significantly correlated with the pH value of digesta of the last part of the small intestine (ρ = −0.361; p = 0.026). All animals enrolled appeared clinically healthy throughout the trial. Growth performance were not affected by the different dietary treatments, but fecal dry matter and pH values were affected in a significant way. Results about the morphology of PPs assessed in this trial can be suggestive of the physical form of the diet as a contributing factor to the onset of different antigenic potentials of the intestinal chyme.

Effect of Concentrate Supplementation on Methane Emission from Grazing Goats

An experiment was conducted to study the effect of strategic concentrate supplementation on methane production in grazing goats using sulfur hexafluoride (SF6) technique. Sixteen male Barbari goats (∼1 year age; BW 18.83±0.65 kg) were divided into two equal groups namely, CONT and SUPL in a completely randomized design. All animals were allowed grazing for 6–7 h on a pasture of known botanical composition. Additionally, goats of SUPL group were supplemented with 250g of concentrate pellet before grazing. After six weeks of experimental feeding, feed intake and digestibility of nutrients were estimated by indicator method. Rumen liquor samples were collected for assessment of fermentation metabolites. The results indicated no significant effect of concentrate supplementation on DM intake. There was significant improvement (P 0.05) by 7.57 and 22.12 percent in SUPL group in comparison to the CONT group. It is concluded that concentrate supplementation significantly improved the nutrient digestibility with no apparent effects on the methane production in grazing goats.

Copper bioavailability, mineral utilization, and lipid metabolism in broilers

The study was conducted to investigate the effects of copper (Cu) sources and levels on mineral utilization, tissue copper residues, and lipid metabolism in Arbor Acres broilers. A total of 640 male broilers were randomly divided into 5 groups with 8 replicates per group and 16 broilers per replicate. The experiment was used in a 2 × 2 + 1 factorial experiment design. Broilers in the control group were fed a basal diet, and animals in the other four groups were fed basal diets supplemented with Cu from copper sulphate and copper methionine. Copper concentrations of the experimental diets were 20 and 40 mg Cu/kg dry matter. A metabolism trial of 4 days was conducted during the last week of experimental feeding. Neither Cu source nor Cu level affected average daily gain, average daily feed intake or feed gain ratio (P &amp;gt; 0.05). Broilers fed 40 mg Cu/kg diets had lower plasma cholesterol than those in the control group (P &amp;lt; 0.05). Copper supplementation decreased (P &amp;lt; 0.05) plasma low-density lipoprotein cholesterol but did not alter plasma high-density lipoprotein cholesterol concentrations or plasma triglyceride concentrations. Copper sulphate supplementation increased (P &amp;lt; 0.05) liver Cu but did not alter pectorals Cu, heart Cu, tibia Cu and tibia P. Broilers fed 40 mg/kg Cu from copper sulphate had a lower (P &amp;lt; 0.05) tibia Ca level. The concentration of liver Cu in the broilers fed copper methionine diets was higher (P &amp;lt; 0.05) than that in those fed copper sulphate. Compared with copper sulphate (100%), the relative bioavailability value of copper methionine was 117%. In conclusion, the relative bioavailability of copper methionine obtained in this study was greater than that of copper sulphate. Copper plays an important role in plasma lipids and in the digestion of dietary Ca in broiler chickens.

Effect of feeding pellet containing Leucaena leucocephala and Ficus infectoria leaves on in vivo methane emission in Barbari goats

Effect of feeding complete pellet feed containing tree leaves on methane emission was studied in male Barbari goats. Three types of complete pellet feed was formulated, viz. control pellet (C) having gram straw (60%) and concentrate mixture (40%), treatment 1 (T1) and treatment 2 (T2) containing dried Leucaena leucocephala and Ficus infectoria leaves respectively. All types of pellets were isonitrogenous. Growing male Barbari goats (12; 3– 4 month-old; average body weight 11.01±0.49 kg) were divided into 3 groups (Gr 1, Gr 2 and Gr 3) as per completely randomized design. Gr 1 was fed with control pellet while Gr 2 and Gr 3 was fed with T1 and T2 pellet respectively. After 6 weeks of experimental feeding, a digestion trial of 6-day duration was conducted. There was no difference in the DMI (g)/day between the 3 groups. Dry matter digestibility and digestibility of other nutrients were comparable among all groups of goats. Rumen liquor was collected from each animal to study rumen fermentation metabolites. Rumen pH, ammonia-N and nitrogenous fractions (total nitrogen, TCA-ppt N, NPN) were statistically similar in all the groups. Total volatile fatty acids (mmol/dl) was significantly higher in Gr 3 (10.57) and Gr 2 (9.52) as compared to control group (8.67). Fractions (%) of volatile fatty acids (acetic acid, propionic acid and butyric acid) were similar in different groups. In vivo methane emission in different groups of goats was estimated by SF6 technique as per procedure standardized in our lab. Methane production (g/day) was 8.29 in Gr 1, 7.47 in Gr 2 and 6.72 in Gr 3. There was 9.89 and 18.93% lower methane production in Gr 2 and Gr 3 as compared to control group of goats fed with complete pellet feed. From the present study, it can be concluded that incorporation of dried L. leucocephala and Ficus infectoria leaves in the complete pellet feed can reduce the methane production in goats.

Protective effects of Sargassum horneri against ammonia stress in juvenile black sea bream, Acanthopagrus schlegelii

Ammonia is an important environmental toxic pollutant that represents a biochemical and physiological hazard to living organisms, especially in intensive culture systems with high stocking density. This study aimed at evaluating the protective effects of Sargassum horneri (SH) on ammonia stress in black sea bream. Four hundred and eighty fingerlings with approximate mean body weight 12.0 ± 0.1 g were randomly distributed into four experimental groups in triplicate. Each group was stocked with 40 fish and fed with isonitrogenous (42% crude protein) and isolipid (12% crude lipid) experimental diets containing either 0% SH (control), 3% SH, 6% SH, or 9% SH in the feed. At the end of 8 weeks of experimental feeding, fish were exposed to ammonia for 24 h. The results indicated that ammonia stress led to an increase in oxidative stress as shown by elevation in the levels of cortisol and liver lipid peroxidative damage markers as well as decrease in antioxidant biomarkers. Furthermore, humoral immunity was suppressed during the stress period. However, fish supplied with S. horneri had significant improvement in immune response, antioxidant capacity, and resistance against ammonia stress, particularly in the 6% SH group. Therefore, dietary S. horneri supplementation at an optimum level of 6% could increase the resistance of juvenile black sea bream to ammonia-induced stress.

Effects of dietary phytoncides extracted from Korean pine (Pinus koraiensis) cone on performance, egg quality, gut microflora, and immune response in laying hens.

This study was conducted to evaluate the effects of dietary phytoncides extracted from discarded Korean pine cones (Pinus koraiensis) on the performance, egg quality, immune response and gut microflora in laying hens. A total of 400 Hy-Line brown laying hens (50-week old) were allotted into four dietary treatments including a control diet or a diet supplemented with phytoncides at 0.002%, 0.004% and 0.008%. During the 6weeks of experimental feeding, 0.008% of dietary phytoncides improved egg production, feed conversion ratio (p<0.05), but not feed intake, egg weight or feed efficiency. Although dietary phytoncides had no effect on egg quality, decreases in Haugh units depending on storage periods were improved by 0.008% of dietary phytoncides (p<0.05). To investigate the roles of dietary phytoncides on the alteration of the immune response during inflammation, lipopolysaccharide (LPS) or saline was intraperitoneally injected into 10 hens per diet group on the end date of the experimental feeding period. Serum immunoglobulins and splenic cytokine expression at mRNA levels were then measured at 4hr postinjection. Although the levels of IgA were decreased by LPS injection in all dietary groups, dietary phytoncides at 0.008% showed a higher level of IgA by LPS (p<0.05). Interestingly, although LPS injection resulted in an enhanced expression of proinflammatory cytokines such as IL-1β and IL-6, dietary phytoncides at 0.008% showed less increased levels of them (p<0.05). Gut microflora was examined from 10 hens per diet group at the end of the experimental period. While the number of Lactobacillus spp. was increased (p<0.05), Escherichia coli counts in the cecal contents were decreased by 0.008% of dietary phytoncides. Taken together, these results demonstrate that dietary supplementation of 0.008% phytoncides improved the egg production, immune responses during inflammation and gut microflora in laying hens.

Effect of dietary manipulation and vaccination of turkey breeder hens on immunoglobulin levels of yolk, yolk sac and neonate poults.

Two hundred turkey breeder hens and 24 viable toms of 30-35weeks age of small white variety were distributed into two treatment groups having four replicates of 25 hens and three toms in each treatment. First four replicates were offered a turkey breeder diet (Diet A) (Nutrient requirements of poultry, 1994, National Academic Press, Washington, DC) and the rest four replicates were maintained on a higher plane of nutrition (Diet B) for 8-week duration. After 6weeks of experimental feeding, two replicates from each treatment groups were vaccinated with ND (R2 B) vaccine. Yolk sac of embryo from birds fed Diet B had a significantly higher (p<.05) IgG, IgM level and HI titre (log 2) than those fed Diet A. HI titre values of embryonic yolk sac from the vaccinated birds fed Diet B were significantly higher (p<.05) than that of the control groups. In addition, HI titre values were significantly higher (p<.05) in the day-old poults of the birds fed Diet B than that of those fed Diet A. There was significantly (p<.01) positive correlation between serum IgG and IgM of the breeder birds and day-old chicks. Similarly, there was significantly (p<.05) positive correlation between yolk IgG and IgM after 1-month experimental feeding and yolk sac IgG and IgM. Positive correlation (p<.05) also existed between yolk sac IgM and day-old chick serum IgM. Furthermore, the HI titres of breeder birds' serum at 14days post-vaccination were positively correlated with their egg yolk after 10 and 15days post-vaccination, yolk sac and day-old chicks. Thus, the study envisaged that a higher immunity in neonate poults from turkey breeders maintained on a higher plane of nutrition may be elicited as there was maternal transfer of antibodies from the serum of breeder birds to their offsprings through their yolk sac.

Moderate and high levels of dietary protein on clinico-biochemical and production responses of lambs to repeated Haemonchus contortus infection

Effect of moderate and high levels of dietary protein and repeated Haemonchus contortus infection on clinical-biochemical and production responses was studied in Chokla lambs. In a 2×2 factorial design, two levels of protein (moderate, MP and high, HP) was supplemented to control (C) and infected (I; challenged with H. contortus) lambs. Thus, twenty-four 4 to 5 months old Chokla lambs (16.8±0.53kg) were randomly distributed into a total of 4 treatment groups of 6 animals each, designated as MPC (moderate protein control), MPI (moderate protein infected), HPC (high protein control) and HPI (high protein infected). The infected groups were drenched with 300 infective larvae (L3)/kg LW on day 0 and subsequently with 400 L3/kg LW three times a week for 10 consecutive weeks. Concentrate was restricted to 2.5% of live weight (LW) and roughage was offered ad libitum. Weekly record of body weight and faecal egg counts (FEC) and bi-weekly assessment of haematological parameters such as haemoglobin, packed cell volume, differential leucocyte count and biochemical parameters such as serum protein, albumin, iron, urea, creatinine and cholesterol were followed during the experimental period of 10 weeks. A metabolism trial was conducted after 8 weeks of experimental feeding to assess N utilization pattern in different groups. Lambs in HP had higher feed and nutrient intake (DM, CP, OM, ME) than MP. Infection exerted a more significant adverse effect on feed and nutrient intake by lambs in MP. Lambs of MPI showed a lower N balance corresponding with a lower N uptake, but had similar utilization efficiency. They also had lower (P<0.05) average daily gain, but no significant effect on body condition score. No clinical signs were evident in infected lambs on varied protein nutrition. Although FEC and adult worm counts were higher in MPI, a varied FEC peak during 4 and 5 weeks in HP and MP, respectively was indicative of non-significant effect of increasing protein nutrition on parasite establishment. However, there was significant improvement in the ability of lambs to withstand the pathogenic effects of H. contortus infection in HPI suggesting that the diet associated with increased resilience. A decreased performance in MPI could be overcome by increasing diet palatability that ensures adequate uptake of protein.

Quality and antioxidant response of gilthead seabream (Sparus aurata L.) to dietary supplements of fenugreek (Trigonella foenum graecum) alone or combined with probiotic strains

The present study was conducted to determine the potential effect of the dietary intake of fenugreek (Trigonella foenum graecum) seeds alone or in combination with Bacillus licheniformis, Lactobacillus plantarum or B. subtilis on gilthead seabream quality and antioxidant response after 2 and 3 weeks of experimental feeding. The results showed that the supplements did not affect the percentage of the fatty acid profiles of muscle, demonstrating that all the additives tested can be administrated without any negative effect on biochemical composition and quality of gilthead seabream. The quantification of thiobarbituric acid reactive substances in muscle demonstrated the significant beneficial effect of the experimental diets compared with the control one. Besides, an increase in superoxide dismutase and catalase in liver was recorded after 3 weeks of administration of experimental diets. Furthermore, real time qPCR revealed that dietary supplementation with FEBS significantly enhances the expression of scavenging enzymes, such as cat and gr genes in the liver after 3 weeks. The findings suggest that the administration of fenugreek supplement alone or combined with probiotic strains could be considered as a good source of natural antioxidants and as a functional aquafeed ingredient for gilthead seabream.

Diet-induced disorders in rats are more efficiently attenuated by initial rather than delayed supplementation with polyphenol-rich berry fibres

The effects of blackcurrant and strawberry fibre on high-fat diet-induced metabolic disorders in rats were compared. The blackcurrant and strawberry preparations were obtained from fruit pomace and contained 66.5 and 51.3% dietary fibre and 4.9 and 5.5% polyphenols, respectively. A high-fat diet was supplemented with the blackcurrant or strawberry fibre for the entire 8 weeks of experimental feeding or for 4 weeks, starting at week 5. Obesity, dyslipidaemia, hyperinsulinaemia and altered microbial metabolism in the distal intestine were noted in rats fed a high-fat diet. The 8-week supplementation with blackcurrant fibre decreased body weight, whereas both fibres decreased epididymal fat mass, increased the caecal concentration of short-chain fatty acids, prevented hyperinsulinaemia and decreased cholesterolaemia. Thus, pomace-derived blackcurrant and strawberry fibre attenuate disorders induced by a high-fat diet; however, initial dietary supplementation is more efficient than the same, but delayed, intervention.