Dry Diet Research Articles

Sea grapesextract improves blood glucose, total cholesterol, and PGC-1α inrats fed on cholesterol- and fat-enriched diet.

Background:Sea grapes orCaulerparacemosahave a lot of phytochemical content,especially unsaturated fatty acids that are beneficial for health. This study aims to evaluate the effects ofsea grapes extracton blood glucose levels, total cholesterol-, and Peroxisome proliferator-activated receptor-gamma coactivator (PGC)-1αin male Wistar rats, which were given per-oral (p.o.) cholesterol- and carbohydrates fat-enriched diets (CFED). Methods: Forty male Wistar albino rats weighing between 200 - 250 g were used for this study. Animals were randomly distributed into four groups of ten animals each. Group A served as control (received standard dry pellet diet). Rats in group B were fed on CFED for 4 weeks.Groups C and D were fed on CFED and were administered 150 and 450 mg/kg of sea grapes extract (p.o.), respectively. Results: Group C rats indicated a blood glucose reduction and an increase in PGC-1αserum, in comparison to group D (p<0.05). There were no significant differences between group C and D in blood cholesterol reduction (high dose of the extract did not have significant effects) (p=0.222), and both groups had the same effect in lowering total cholesterol in rats. Conclusion:Sea grapes extract is proven to improve blood glucose, total cholesterol, and PGC-1αlevels in rats fed with CFED.

Feeding ecology and diet of the southern geladas (Theropithecus gelada obscurus) in human-modified landscape, Wollo, Ethiopia.

Studying the dietary flexibility of primates that live in human‐modified environments is crucial for understanding their ecological adaptations as well as developing management and conservation plans. Southern gelada (Theropithecus gelada obscurus) is an endemic little‐known subspecies of gelada that inhabits human‐modified landscapes in the northern central highlands of Ethiopia. During an 18‐month period, we conducted this intensive study in an unprotected area of a human‐modified landscape at Kosheme in Wollo to investigate the feeding ecology of southern geladas and their dietary responses to seasonal variations. We quantified the monthly and seasonal diet data from a band of southern geladas using instantaneous scan sampling method at 15‐min intervals, and green grass phenology and availability using visual inspection from the randomly selected permanent plots. The overall average diet of southern geladas at Kosheme constituted grass blades 55.4%, grass undergrounds 13.2%, grass bulbs 5.6%, grass seeds 5.4%, herb leaves 4.0, fruits 7.3%, and cereal crops 5.6%. Grass blade consumption increased with increasing green grass availability, while underground food consumption increased with decreasing green grass availability, and vice versa. Southern geladas spent significantly more time feeding on the grass blades and herb leaves and significantly less time on bulbs during the wet season than the dry season. Underground grass items (rhizomes and corms) were not consumed during the wet season, but made up 22.3% of the dry season diet. Thus, although grass blades are staple diet items for geladas, underground diet items are important “fallback foods” at Kosheme. Our result shows insights into the dietary flexibility southern geladas adopt to cope with human‐modified landscapes of the north‐central Ethiopian Highlands. Thus, the study contributes to a better understanding of how changing environments shape primate ecology and evolution.

Effect of Nanosilica and Bentonite as Mycotoxins Adsorbent Agent in Broiler Chickens' Diet on Growth Performance and Hepatic Histopathology.

Simple SummaryMycotoxins cause significant economic losses in feed ingredients, nutritional value, feed palatability, and the poultry industry. Thus, there is a need for ways to eradicate or inactivate mycotoxins in chicken feed. The present feeding trial aims to evaluate the use of nanosilica and bentonite to prevent the harmful effects of a mycotoxin-contaminated diet on broiler performance, histopathological, and carcass traits. The obtained results revealed significant improvements in broiler growth performance resulting from the addition of nanosilica at 0.20% and bentonite at 0.50%. Additionally, the hepatoprotective efficacy of nanosilica was evident at different dose levels. Consequentially, it could be used in broiler’s contaminated diets without negatively affecting birds’ health.Mycotoxins are toxic secondary metabolites produced by different strains of fungi, such as aspergillus, fusarium, and penicillium that can contaminate feed ingredients or the entire feed of poultry and animals. Mycotoxins can cause many serious complications to both humans and animals due to carcinogenic, mutagenic, and immunosuppressive disorders. Therefore, the present experiment aims to investigate the effect of broiler chickens’ diets supplemented with different levels of nanosilica (NS) as an adsorbent agent of mycotoxins on their growth performance and hepatic histopathology. Detectable levels of toxins were present in the feed before feeding, and all levels of mycotoxins were above the normal limit. A total of 180 one-day-old male Arbor Acres broiler chickens were allocated randomly to six treatment groups with three replicates per group, including ten chickens per replicate. The experiment lasted for five weeks, and dietary treatments included control diet and diets with four levels of nanosilica as 0.05%, 0.10%, 0.15%, and 0.20% as well as 0.50% bentonite (fixfin® Dry) diet. Bodyweight, body weight gain, average daily feed intake, and feed conversion ratio were measured weekly. At the end of the fifth week, six chickens per treatment were sacrificed to investigate the effects of NS and bentonite on carcass characteristics and hepatic histopathology. The results showed that providing broiler chickens’ diets with an adsorbent agent, such as NS or bentonite, can reduce the side effects of mycotoxins and enhance their growth performance. The best record was achieved with NS at 0.20%, compared with the control group and other dietary treatment groups. Accordingly, 0.20% of NS could be used in broiler chickens’ diets to minimize the harmful effects of mycotoxins.

Feeding the European hedgehog (Erinaceus europaeus L.)-risks of commercial diets for wildlife.

The supplemental feeding of wildlife is a worldwide phenomenon. The most widespread and socially accepted example is bird feeding. Commercial hedgehog (Erinaceus europaeus L.) diets are readily available in Switzerland. To test the hypothesis that commercial hedgehog diets are nutritionally inadequate, the following parameters (as taken from the label) of five commercial diets (three dry and two wet) were compared to the natural diet of E.europaeus: List of feed materials, crude ash (CA), crude protein (CP), crude fibre (CF), ether extract (EE) and nitrogen-free extracts (NfE). To test the second hypothesis, that feed labels of commercially available hedgehog diets in Switzerland are in accordance with Swiss and European law, the following parameters were assessed: Type of feed, net quantity, moisture content, instructions for proper use, list of the feed materials and claims. In all dry diets, the first ingredient was cereals (38.8%-50%), whereas in both wet diets, it was meat and meat by-products (51% in one product). Only one product had a CP content comparable to that of the natural diet and four products had a higher NfE content. Overall, the wet products were more comparable to the natural diet, especially regarding CP and NfE content. Of the five examined diets, three were labelled as complete feeds and two as compound feeds. The label analysis revealed inaccuracies and possible misleading information on two products. In conclusion, the use of commercial dry hedgehog diets should be discouraged as they do not resemble the natural diet of E.europaeus and are likely nutritionally inadequate. The commercial wet hedgehog diets should only be used supplementary. The feed labels of commercially available hedgehog diets were not always in compliance with Swiss and European law. The public should be educated about feeding E.europaeus and the risks of commercial diets for wildlife.

Effect of replacing darkness with dim light in the larviculture of red snapper, Lutjanus campechanus

Progress towards the development of reliable hatchery technology for red snapper, Lutjanus campechanus, has been limited by inconsistent spawning and difficulties in larval rearing. We report on recent progress to improve this technology. A larval rearing trial assessing the effects of two different photoperiods was conducted at the University of Miami Experimental Hatchery (UMEH). Four 400-L tanks were subjected to a photoperiod of 16 h of full spectrum light, and four 400-L tanks were subjected to 16 h of full spectrum light and 8 h of dim light through 11 days post hatch (dph). S-strain rotifers, Brachionus rotundiformis, were used as the exclusive first feeding source and were maintained at a density of 25 ml−1 throughout the experimental period. Standard length, swim bladder inflation, and feed consumption were measured for each tank at 3, 6, 9 and 12 dph. Survival was quantified at 12 dph and at the completion of weaning onto dry feeds at 40 dph. No significant differences in growth, feed consumption, or survival rates were observed between treatments at the conclusion of the trial. However, tanks exposed to a treatment involving 8 h of dim light showed completion of swim bladder inflation in 92.5 ± 10.8 % of larvae sampled by 9 dph, while tanks maintained with 16 h of light and 8 h of darkness showed a significant reduction with only 60 ± 2.5 % swim bladder inflation at this sample date (p = 0.0131). By 12 dph, all larvae in all tanks showed >95 % swim bladder inflation success. Total survival across treatment groups through 13 dph was 66 ± 8.0 % and 4.6 ± 1.0 % at 40 dph when the larvae were fully weaned onto dry diets.

Studies on growth performance of Cyprinus carpio var. Communis fed with Bacillus clausii supplemented diets

The present investigation entitled “Studies on growth performance of Cyprinus carpio var. Communis fed with Bacillus clausii supplemented diets” was carried out at Faculty of Fisheries, Ganderbal over a period of 60 days from April 1st to June Ist, 2019. The fingerlings were fed with dry diets containing three concentrations of probiotic viz., (T1: 1%, T2: 1.5%, T3: 2%) and control group (T0: containing no probiotic). The growth parameters including per cent weight gain, Specific growth rate (SGR), feed conversion ratio (FCR), feed efficiency ratio (FER) and protein efficiency ratio (PER) were measured at the end of the experiment. The results showed that the probiotic incorporated diets had significant impact on growth than control group (P&lt;0.05). The highest values of treatment T2 with 2 per cent probiotic showed the highest percent weight gain (74.62%), specific growth rate (0.40), feed efficiency ratio (0.90), protein efficiency ratio (1.82) were observed in treatments with 2% concentration of probiotic where as, feed conversion ratio(1.09) was lower in groups received probiotic through diets than control.

In vivo and in vitro Digestibility of an Extruded Complete Dog Food Containing Black Soldier Fly (Hermetia illucens) Larvae Meal as Protein Source.

Growing attention is being directed toward insects as a novel and sustainable source of protein for pet food. The aim of the study was to evaluate nutrient digestibility of a diet containing black soldier fly larvae as its main protein source. Moreover, the purpose of the study was to compare the traditional in vivo total collection method with the in vivo marker method and in vitro digestibility method. Two isonitrogenous and isoenergetic dry diets containing either venison meal (CTRL diet) or black soldier fly larvae meal (BSF diet) as their primary sources of proteins were fed to six adult dogs, according to a Latin square design. The digestibility of nutrients was determined using both in vivo (“total collection” and “internal marker” approaches) and in vitro methods. The two diets showed similar nutrient digestibility values for dry matter, organic matter, ether extract, ash, and phosphorus. However, a statistical trend (p = 0.066) was observed indicating greater protein digestibility in the BSF diet compared with the CTRL diet. Calcium digestibility was higher in the BSF diet compared with the CTRL diet (p = 0.018). On the contrary, fiber digestibility was lower in the insect-based diet compared with the venison diet (p < 0.001). There was no difference between total collection and internal marker methods in the assessment of in vivo digestibility for any of the nutrients considered. The in vitro digestibility values for dry matter, organic matter, and crude protein, as well as the estimated in vivo digestibility of organic matter and crude protein by the means of the predictive equation, were aligned with the in vivo results, although in vitro estimations were consistently higher compared with those obtained by in vivo analysis. Digestibility analysis of a dog food containing insect meal as the sole source of protein (36.5% inclusion) showed promising results in terms of it presenting similar values as a meat-based diet, indicating its suitability as a sustainable protein source for pet food. Moreover, the study showed that both the in vivo marker method and the in vitro method could be possible alternatives to the traditional total collection method in digestibility trials.

Dietary niacin requirement of fingerling Indian major carpCatla catlaHamilton

A feeding trial was conducted to determine the dietary niacin requirement of fingerling Catla catla. Eight casein–gelatin based isonitrogenous (350 g/kg CP) and iso-caloric (16.72 kJ/g GE) test diets with graded levels of niacin (0, 10, 20, 30, 40, 50, 60 and 70 mg/kg diet) were formulated and fed to triplicate groups of fingerlings (3.5 ± 0.5 g) to apparent satiation thrice daily for 16 weeks. Live weight gain (LWG%), feed conversion ratio (FCR), protein efficiency ratio (PER%) and protein productive value (PPV) improved significantly (p < .05) with the incremental levels of dietary niacin up to 30 mg/kg diet beyond which no significant (p > .05) difference was observed in above parameters. RNA/DNA ratio also increased significantly (p < .05) as dietary niacin levels increased from 0 to 30 mg/kg, and thereafter remained unaffected with further inclusion of niacin. Blood indices including haematocrit (Hct), haemoglobin (Hb) and RBCs counts were significantly (p < .05) affected by varying levels of dietary niacin and also found to be highest in fish fed 30 mg/kg niacin. However, liver niacin concentration increased significantly (p < .05) with increasing dietary niacin levels up to 40 mg/kg diet indicating liver niacin saturation at this level. Broken-line regression analysis of LWG, FCR, PPV and liver niacin concentrations against varying levels of dietary niacin indicated the break points at 27.71, 27.81, 30.75 and 40.64 mg niacin per kg of the dry diet, respectively. On the basis of the results obtained through regression analysis of above parameters, inclusion of 31.72 mg/kg niacin diet is recommended for fingerling C. catla.

Feline ureteral obstruction: a case-control study of risk factors (2016-2019).

Ureteral obstruction (UO) in cats causes acute kidney injury and typically requires surgical intervention. Information is required about potentially modifiable risk factors to inform prevention strategies. A case-control study was performed to assess risk factors associated with feline UO. Cases were defined as cats with either of the following: (1) ureteral obstruction (ureteroliths: 13/18; unknown: 5/18) confirmed with pyelography; or (2) a creatinine concentration >140 µmol/l with both UO (ureteroliths: 6/10; blood clots: 3/10; pyonephrosis: 1/10) and pyelectasia ⩾5 mm on abdominal ultra sonography. Controls were defined as cats without evidence of UO on history, physical examination and abdominal ultrasound. Age, sex, breed (domestic shorthair/longhair), diet (predominantly dry, mixed or predominantly moist food), housing (indoors or mixed) and plasma total calcium were evaluated for their association with UO using multivariable logistic regression. A receiver operator characteristic (ROC) curve was created to evaluate the predictive ability of the final model. In total, 168 cats (28 cases, 140 controls) were included. Age, sex, breed, housing and total calcium were not significantly associated with UO; however, diet was. Compared with cats eating a predominantly moist food diet, cats fed a predominantly dry food diet were 15.9 times more likely to develop a UO (95% confidence interval 2.9-295; P = 0.009). There was no difference in the association between diet and UO in cats fed a mixed diet vs cats fed a predominantly moist food diet (P = 0.25). The area under the ROC curve was 72%. Changes in diet formulation could provide a simple and economical method to reduce the risk of UO.

Extracorporeal acidic predigestion of commercial dry diets can reduce the incidence of body deformities in the stomachless fish crucian carp (Carassius carassius L.)

Abstract The aim of the present study was to test the hypothesis that predigesting commercial dry diets for fish with hydrochloric acid (HCl) can contribute to the reduction of the incidence of body deformities in a stomachless cyprinid species intensively reared under controlled conditions. Two different dry diets (Carpco Crumble by Coppens International and Aller Futura by Aller Aqua), their respective variants modified with HCl, and frozen larval chironomids (control diet) were fed as sole food sources to juvenile Carassius carassius in a recirculating aquaculture system at 25°C for 60 days. At the end of the experiment, visible body deformities occurred exclusively in the groups fed dry diets. The shares of deformities were significantly lower in fish groups fed the modified diets (6.1–13.2%) as compared to those fed the original ones (74.0–87.0%). Fish in the latter groups had significantly the highest condition factor values, which indicated a possible phosphorus deficiency. As evidenced by our results, predigesting commercial dry diets with HCl can be a useful method to mitigate the problem of body deformities occurring in intensively fed cyprinid species.

Impact of Feeding Cover Crop Forage Containing Brassicas to Steers during Backgrounding on Palatability Attributes of Beef Strip Steaks.

Brassica cover crops have been widely used for improving soil health and as a feed resource for grazing cows, but their use in backgrounding diets is unknown. The objective of this study was to determine the impact of feeding a brassica cover crop mixture during backgrounding on beef palatability. Thirty steers were assigned to one of two dietary treatments during backgrounding with (1) ad libitum access to freshly cut brassica cover crop forage (CC) containing radish, turnip, rapeseed, and rye grass, or (2) common Midwestern dry lot backgrounding diet (CON). The steers were transitioned to a common finishing diet after backgrounding. Striploins were collected after harvest, and were analyzed for evaluation of the Warner–Bratzler shear force (WBSF), collagen content, autolysis of calpain-1, proteolysis of desmin, and troponin-T; in addition, the tenderness, juiciness, and flavor evaluated by a trained sensory panel. A treatment x day interaction was observed for WBSF (p = 0.02). Steaks from the CON diet were less tender than CC steaks on days 3 and 7, but did not differ on days 14 and 21. Feeding a brassica mixture cover crop during the backgrounding phase of production did not impact the collagen content, autolysis of calpain-1, or proteolysis of desmin and troponin-T. Thus, additional investigation into the mechanisms responsible for the differences observed in instrumental tenderness is warranted.

Apparent total tract nutrient digestibility and metabolizable energy estimation in commercial fresh and extruded dry kibble dog foods.

Commercial fresh cooked foods have started gaining popularity among American dog owners in recent years. However, nutrient digestibility and the estimation of metabolizable energy (ME) of commercial fresh dog foods remain inadequately understood, even though both measures are critical to provide the intended calories for the target animal. In this preliminary study, different cohorts of normal-weight dogs were fed one of five test diets of comparable macronutrient composition: a chicken-based extruded dry kibble diet (n = 12), and chicken- (n = 12), beef- (n = 6), pork- (n = 6), or turkey-based fresh food (n = 6) for 10 d. Daily food intake and fecal characteristics were recorded, and fecal samples were collected for nutrient analysis. Despite comparable dry matter (DM) and caloric intakes between the two chicken-based diets, the fresh diet led to lower defecation frequency (1.2 ± 0.2 vs. 1.7 ± 0.5 times/d, adjusted P < 0.001), lower fecal DM (24 ± 8 vs. 47 ± 10 g/d, adjusted P < 0.001), and lower fecal calories (92 ± 31 vs. 189 ± 43 kcal/d, adjusted P < 0.001) than the kibble diet. The apparent total tract digestibility of DM, protein, fat, nitrogen-free extract, and calories of the kibble diet were all significantly lower than any of the fresh diets (adjusted P < 0.001 for all). Measured ME per food DM in all of the fresh diets, except the pork-based recipe, was significantly higher than that of the kibble diet (adjusted P < 0.001 for all). For the kibble diet, the modified Atwater calculation underestimated the ME and the NRC 2006 calculation was the most accurate predictor of ME. The standard Atwater calculation performed best for the two fresh diets that had the highest fat content (chicken, beef) and the NRC 2006 calculation performed best for the fresh diet that had the highest protein content (pork). ME of the turkey-based diet was equally overestimated and underestimated with the standard Atwater and NRC 2006 methods, respectively. We propose that commercial and home-prepared fresh diets should be assessed using standard Atwater factors as commonly done in human nutrition, or preferably for commercial products, by direct measurement in conforming feeding trials.

Nutritional evaluation of commercial dry dog foods available on the Czech market.

The evaluation of the quality of commercial diets is a topic of interest to dog owners and veterinarians. The aims of the study were to determine proximate analysis, metabolizable energy and some amino acids in dry dog diets for different ages, divided into three groups G1 (low price, grains included), G2 (medium price, grains included) and G3 (high price, grain-free). The hypothesis was tested that there are significant differences in the analysed values between dry dog diets from different price categories and between grain-free and grain-containing diets. Furthermore, the analysed values were compared with AAFCO and FEDIAF recommendations and with label values guaranteed by manufacturers to see whether there are any deviations. We analysed 60 samples of complete dry dog diets purchased in the Czech Republic, using the standard AOAC methods of proximate analysis. Metabolizable energy was calculated using the NRC equation, and 30 samples were analysed for selected amino acids. The results showed that there are significant differences in protein and amino acid contents between grain-free (G3) and grain-containing (G1,2) dog diets. G3 diets had significantly (p<0.01) higher crude protein and essential amino acid contents. No significant differences were found between grain-containing diets G1 and G2. The results may indicate a higher proportion of animal components and a lower content of carbohydrates in G3 diets. Most of the tested dog diets met the AAFCO and FEDIAF recommendations. There were only a few deviations in threonine in G1 and G2 diets for growing dogs.

254 Evaluation of Different Corn Milling Methods for High-moisture and Dry Corn on Finishing Cattle Performance and Carcass Characteristics

Abstract Steers (n=600; Initial BW = 402 ± 17 kg) were fed for134 day to evaluate the effect of milling method and corn type on performance and carcass characteristics. Treatments were evaluated as a 2 × 3 factorial with factors being milling method (Automatic Ag® roller mill or hammer mill) and corn type (100% high-moisture, 100% dry, or 50:50 blend of high-moisture and dry corn). High-moisture corn was processed at harvested based on respective treatment and ensiled until trial initiation. Both dry corn and HMC were processed using a 16-mm screen in the hammer mill and the roller mill was adjusted to ensure all kernels were broken. There were no interactions between milling method and corn type for final BW, daily gain (ADG), or dry matter intake (DMI; P ≥ 0.32), but there was a tendency for an interaction for G:F (P = 0.09). Cattle fed 100% high-moisture corn processed with the Automatic Ag roller mill were 4.7% more efficient (P ≤ 0.01) with 55% lower fecal starch (P &amp;lt; 0.01) compared to high-moisture corn processed with the hammer mill. Cattle fed dry corn tended (P = 0.07) to have a greater live final BW regardless of milling type and had the greatest DMI (P ≤ 0.01) Intake decreased as high-moisture corn was increased in the diet. Due to no differences in ADG with lower DMI led to a 6% improvement (P ≤ 0.01) in G:F for steers fed HMC. There were no further effects (P ≥ 0.14) on performance or carcass traits regardless of milling method or corn type. Processing high-moisture corn using Automatic Ag roller mill improved feed efficiency compared to processing with a hammer mill when corn was included at 70% of the diet, but processing method had little effect when fed as dry corn or blended diets.

Influence of Cane Molasses Inclusion to Dairy Cow Diets during the Transition Period on Rumen Epithelial Development.

Simple SummaryThe rumen epithelium of dairy cattle undergoes a transformation in response to dietary and physiological changes. Rumen papillae development and adaptation from a typical dry cow diet to a lactating diet can require a substantial amount of time, subsequently limiting the amount of volatile fatty acids (VFA) absorbed from the rumen during early lactation. Infusions of butyrate into the rumen of sheep stimulates cellular proliferation of rumen epithelial tissue, which may prove beneficial for ruminal papillae development in dairy cows during the dry period. However, no studies have investigated mechanisms associated with rumen epithelial adaptation in periparturient dairy cattle. Our hypothesis was that supplementation with cane molasses containing 34% sucrose during the prepartum period would stimulate ruminal butyrate production and ultimately promote ruminal papillae development and absorption rate, thus increasing dry matter intake (DMI) and milk production during the postpartum period. Results from these experiments indicate that diets containing cane molasses during a 60 day dry period can positively influence transition cow performance. The objective of this study was to evaluate the addition of cane molasses during a 60 day dry period on performance and metabolism of Holstein cows during prepartum and postpartum periods. For experiment 1, 26 primiparous and 28 multiparous cows were used. Upon freshening, all cows were offered a common lactation diet. For experiment 2, six multiparous cows fitted with rumen cannulas were used to measure performance and metabolism, following the same protocol as experiment 1. Ruminal propionate increased by 10% during both prepartum and postpartum periods; however, papillae area was greater for cows not fed molasses, and volatile fatty acids (VFA) absorption from the rumen was not increased, resulting in similar glucagon-like-peptide-2 receptor (GLP-2R) density. The improved dry matter intake, when molasses was added into prepartum diets, translated into increased milk yield and energy-corrected milk (ECM) in Experiment 1 only for multiparous cows. For experiment 2, the improvement on milk performance was also observed, where cows fed molasses had 18.5% greater ECM production. Feeding molasses during a 60 day dry period positively influenced transition cow performance, and it was not accompanied by changes in rumen morphometrics; however, this indicates enhanced adaptation by the rumen epithelium based on similar capabilities for VFA absorption.

Effects of dietary arginine levels on growth, immune function of physical barriers and serum parameters of spotted seabass (Lateolabrax maculatus) reared at different water temperatures

A growth experiment was conducted to investigate the effects of dietary arginine levels on growth, immune function of physical barriers and serum parameters of spotted seabass (Lateolabrax maculatus) reared at different water temperatures (27°C and 33°C). Six iso‑nitrogenous and iso‑lipid diets were formulated with 1.16%, 1.65%, 2.04%, 2.44%, 2.98% and 3.36% arginine, respectively. Growth of fish reared at 27°C was significantly higher than that of fish reared at 33°C (P < 0.05). Weight gain (WG) increased first and then decreased with the increase of arginine levels, and the maximum value was obtained in fish fed the diet with 2.04% arginine at 27°C or 33°C. As for immune function of physical barriers, activities of antioxidant enzymes (GPx and SOD) and expression of genes related to tight junction (ZO-1, Occludin and Claudin b) were significantly higher in the gills of fish reared at 27°C than those of fish reared at 33°C (P < 0.05). Furthermore, activities of GPx and SOD and the mRNA expression of ZO-1, Occludin and Claudin b reached the maximum values in the gills of fish fed the diet with 2.44% or 2.04% arginine at 27°C among all treatments. The mRNA expression of MAPK p38 and MyD88 and contents of pro-inflammatory cytokines (IL-1β, IL-6 and TNFα) were significantly lower in the intestine of fish reared at 27°C than those of fish reared at 33°C (P < 0.05). Regardless of water temperature, contents of IL-1β, IL-6 and TNFα as well as the mRNA expression of MAPK p38 and MyD88 reached the minimum values in the intestine of fish fed the diet with 2.04% or 2.44% arginine at 27°C among all treatments. As for serum parameters, the activity of iNOS as well as contents of NO, complements 3 and 4 were significantly higher in fish reared at 27°C than those of fish reared at 33°C (P < 0.05). Regardless of water temperature, serum activities of TNOS and iNOS reached the maximum values in fish fed the diet with 2.04% or 2.44% arginine among different arginine supplementation groups. The activity of lysozyme reached the maximum value in fish fed the diet with 2.04% arginine level at 27°C among all treatments. Those results showed that a water temperature of 33°C decreased growth, immune function of physical barriers and serum parameters of fish. Growth and immunity were maximized when the arginine requirement of spotted seabass was met. Second-order polynomial regression analyses of WG and lysozyme activity showed that the arginine requirement of spotted seabass was 2.47% and 2.53% of the dry diet (5.49% and 5.62% of dietary protein) at 27°C as well as 2.40% and 2.37% of the dry diet (5.33% and 5.27% of dietary protein) at 33°C, respectively.

An evaluation on taurine addition in the diet of juvenile sea cucumber ( Apostichopus japonicus ): Growth, biochemical profiles and immunity genes expression

A 60-day feeding trial was conducted to evaluate the effects of dietary taurine (Tau) levels on the growth, biochemical profiles and related immune gene expression of sea cucumbers (Apostichopus japonicus). A total of 225 sea cucumbers (initial body weights 0.79 ± 0.05 g) were randomly stocked into 5 groups (three tanks per group) and received one of the following diets: Each diet was supplemented with 0 g/kg (T0), 5 g/kg (T0.1), 10 g/kg (T0.5), 20 g/kg (T1) or 50 g/kg (T2) Tau. The sea cucumber weight gain rate, specific growth rate, feed efficiency and crude protein content increased in Tau-supplemented groups compared with T0 group. The body wall total amino acids and total essential amino acids in Tau-supplemented groups were significantly lower than in T0 group while the Tau contents were significantly higher. The acid phosphatase, alkaline phosphatase and complement 3 values were significantly increased in T0.5/T1. Meanwhile, total superoxide dismutase activities in T0.1, T0.5 and T1 were significantly higher than T0 group. The intestinal ATP synthase, Aj-p105, Aj-lys and AjTRX gene expression levels were significantly increased in Tau supplementation groups than in T0 group. And Tau optimum content in the diet of juvenile sea cucumber was determined as 3 g/kg of the dry diet.

Study on partial replacement of fish meal with concentrated dephenolized cottonseed protein in feed ofPenaeus monodon

The effects of partial replacement of fish meal with concentrated dephenolized cottonseed protein (CDCP) in feed on growth performance, feed utilization, nonspecific immune responses and gut morphology were studied in black tiger shrimp (Penaeus monodon) using 8-week feeding trials. Five isonitrogenous and isolipidic diets were formulated to contain five graded levels of CDCP (0%, 5%, 10%, 15% and 20%). Each diet was randomly assigned to triplicate groups of 30 shrimp (0.80–0.84 g). Maximum weight gain rate (WG), specific growth rate (SGR), survival rate (SR), apparent feed dry matter digestibility and the number of intestinal folds were recorded at 10% dietary CDCP. Dietary CDCP levels had no significant effect on serum superoxide dismutase (SOD) and malondialdehyde (MDA), (p > 0.05). Intestinal microstructures were positively affected by dietary CDCP at the optimal level of 10%, significantly increasing fold height and flod numbers (p < 0.05). Based on the growth performance, feed utilization, proximate composition, enzyme activities and gut morphology, the optimum dietary CDCP level for optimal growth of P. monodon was 10% of the dry diet, corresponding to the replacement ratio of fish meal 33.33%. The results provide a theoretical basis for the designing of feed formulation for black tiger shrimp (P. monodon).

Controlled trial of the effect of negative dietary cation-anion difference on postpartum health of dairy cows

The objective of this study was to assess the effects of feeding negative dietary cation-anion difference (DCAD) dry cow diets on postpartum health. Cows from 4 commercial dairy farms in Ontario, Canada, were enrolled in a pen-level controlled trial from November 2017 to April 2019. Close-up pens (1 per farm), with cows 3 wk before expected calving, were randomly assigned to a negative DCAD [TRT; -108 mEq/kg of dry matter (DM); target urine pH 6.0-6.5] or a control diet (CON; +105 mEq/kg of DM with a placebo supplement). Each pen was fed TRT or CON for 3 mo (1 period) then switched to the other treatment for the next period, with 4 periods per farm. Urine pH was measured weekly until calving, and body condition score (BCS) was measured at enrollment and at 5 wk postpartum. Data from 15 experimental units [8 TRT and 7 CON, with 1,086 (TRT: n = 681; CON: n = 405) observational units (cows)] that received the assigned diet for >1 wk were included. The incidence of milk fever (MF), retained placenta (RP), metritis, hyperketonemia (blood β-hydroxybutyrate >1.2 mmol/L, measured weekly in wk 1 and 2), clinical mastitis within 30 DIM (MAST), displaced abomasum (DA) within 30 d in milk (DIM), purulent vaginal discharge (PVD, assessed once at wk 5), and number of disease events (≥1 or ≥2) were analyzed with logistic regression models with treatment, parity, BCS, and their interactions, accounting for pen-level randomization and clustering of animals within farm with random effects, giving 10 degrees of freedom to test treatment effects. Multiparous cows fed TRT had greater blood calcium between 1 and 4 DIM than multiparous cows fed CON, and the prevalence of subclinical hypocalcemia (total Ca ≤2.14 mmol/L) was lesser when fed TRT compared with CON (d 1: 73 ± 6% vs. 93 ± 4%; d 2: 65 ± 7% vs. 90 ± 5%), with no differences between treatments detected in primiparous cows. We detected interactions of treatment and BCS at enrollment for MF in multiparous cows and of treatment and parity for ≥2 disease events. Overconditioned (BCS ≥3.75) multiparous cows had reduced incidence of MF when fed TRT (TRT: 2 ± 1%, vs. CON: 13 ± 8%). We detected no treatment effects on RP, metritis, hyperketonemia, or PVD incidence. Cows fed TRT had lesser incidence of DA (1.7 ± 0.7% vs. 3.6 ± 1.6%) and tended to have lesser incidence of MAST compared with CON (1.8% ± 0.6% vs. 4.4 ± 1.4%). No treatment effect was detected on ≥1 disease events (TRT: 38 ± 7%, vs. CON: 42 ± 8%); however, multiparous cows on TRT were less likely to have ≥2 disease events than cows on CON (14 ± 4% vs. 23 ± 6%). Under commercial herd conditions, feeding prepartum diets with negative DCAD improved several measures of postpartum health.

Somatic growth and gonadal development of Paracentrotus lividus (Lamarck, 1816) fed with diets of different ingredient sources

Sea urchins’ gonads are a delicacy highly appreciated worldwide. In Europe, Paracentrotus lividus is one of the most valuable edible sea urchin species and a desired target for aquaculture. One of the challenges of echinoculture is to increase the sea urchins’ growth rate during the on-growing phase and reducing the production cycle required to obtain sea urchins of commercial size (test diameter ≈ 50 mm). The present study aimed to evaluate the growth and gonad development of P. lividus urchins fed with three dry diets for 15 weeks. The diets were formulated with ingredients of three different sources: an algae-based, a fishmeal-based and a cereals-based diet. The somatic growth was assessed by biometric indicators like the linear and specific growth rates. The gonadal development was assessed by the gonadal somatic index (GSI), gametogenesis level, proximate composition and fatty acids profile. The results obtained showed high growth rates in all the three diets tested (0.44% per day). The sea urchins fed with the cereals diet presented the highest GSI (8.22%) with higher proportion of gonads in growing and premature stages. The proximate composition of the sea urchins’ gonads was significantly affected by diet and sea urchins’ sex, particularly the lipid content. Concomitantly, fatty acids (FA) profile of the gonads was influenced by both diet and sea urchins’ sex with saturated and polyunsaturated FA playing an important role in this differentiation.