Feeding Level Research Articles

Toxicological risk assessment of triadimenol for human exposure, broiler health, and food safety

Triadimenol, a widely used triazole fungicide, leaves residues that pose risks to broiler health, food safety, and human health. Current studies focus on lab animals, leaving limited data regarding its impact on non-target organisms in agricultural ecosystems. Moreover, the doses in current studies often exceed typical agricultural pollution levels of triadimenol. Therefore, this study evaluates the toxic effects of triadimenol by exposing broilers to different concentrations (0.05-20 mg/kg) in their feed for 42 days, assessing growth performance, organ index, hematological parameters, histopathology, jejunum morphology, and tissue residues. The results show that triadimenol contamination at 0.05-20 mg/kg in feed does not significantly affect broiler growth performance. However, the significant changes in hematological parameters suggest the potential hematological toxicity of triadimenol in broilers. Triadimenol at 1 mg/kg or higher induces hepatotoxic and nephrotoxic effects, and significantly alters kidney organ index and histopathology in broilers. Additionally, when the triadimenol contamination level in feed exceeds 1 mg/kg, the residues in edible tissues of broilers exceed the limits set by the EU and China. Overall, our study indicates that even low-dose exposure to triadimenol poses potential risks, highlighting the need for strict regulation of its use in agriculture to protect food safety and human health.

Development Of A User-Friendly Automated Poultry Feeding System

The huge cost and high labor demand associated with the current deep litter system of poultry farming poses a great challenge to poultry farming. These drawbacks which currently threatens this system of farming, have been attributed to the over-involvement of humans in almost all aspects of operation of this farming system. The consequences are increased disease outbreak, weakness and poor bird feeding. To ameliorated some of these challenges, an automated poultry feeding system is developed and presented in this paper. The proposed system mimics the roles of real-life poultry attendants in delivery of feed and water to birds at specified interval of time. The system controls the dispensing of poultry feed (liquid and solid) through a program written on ATmega328P microcontroller via the Arduino Uno. The system senses the level of feed and water in the respective trough and intelligently dispense water and feed in response to the sensed levels. The current system is able to effectively sense and predict the level of feed and water in the farm at an accuracy of 98.79% and dispense same within a response time of 50-60ms.

Sugarcane, corn silage and concentrate levels in cattle diet

This study evaluated two roughage types (sugarcane and corn silage) and two concentrate feed levels (0 and 25% of the total dry matter) in the cattle diet, in a 2x2 factorial design, and compared passage rate measurements (indicator and rumen evacuation). Four Holstein-Zebu heifers cannulated in the rumen and ileum were evaluated, in a 4x4 Latin square design. Stool samples (8th - 10th day) and rumen fluid (8th day) were collected and the rumen was emptied (14th and 16th day). Treatments were compared by contrast, evaluating the effects of roughage, concentrate feed and interaction between these factors. Dry matter (DM) intake and neutral detergent fiber corrected for ash and protein (apNDF) were highest for animals fed corn silage, and DM and organic matter (OM) intake were highest when fed concentrate. There was no roughage effect on ruminal mass, but concentrate decreased ruminal NDF in the total digesta mass. The coefficients of total digestion of crude protein (CP), apNDF and non-fiber carbohydrates (NFC) were higher for sugarcane than corn silage. Concentrate feed improved the total digestibility of OM and NFC. Passage rates evaluated by the marker technique and rumen evacuation were similar. Corn silage or 25% concentrate in the cattle diet improved consumption, intake rate and nutrient digestibility. The particle passage rate can be estimated by rumen evacuation or by adjusting a nonlinear mathematical model.

Safety and efficacy of a feed additive consisting of an essential oil derived from the flowering stems of Salvia sclarea L. (clary sage oil) for use in all animal species (FEFANA asbl).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of an essential oil from the fresh or dried flowering stems of Salvia sclarea L. (clary sage oil) when used as a sensory additive in feed and in water for drinking for all animal species. The EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) concluded that the additive under assessment is considered safe up to the maximum use level in complete feed of 15 mg/kg for veal calves (milk replacers), cattle for fattening, sheep/goats, 10 mg/kg for horses, 20 mg/kg for dogs, salmonids and ornamental fish. For the other target species, the calculated safe concentrations were 5 mg/kg for chickens for fattening, 8 mg/kg for laying hens, 7 mg/kg for turkeys for fattening, 9 mg/kg for piglets, 11 mg/kg for pigs for fattening, 14 mg/kg for sows, 13 mg/kg for dairy cows, 8 mg/kg for rabbits and 4 mg/kg for cats. These conclusions were extrapolated to other physiologically related species. For any other species, the additive is safe at 4 mg/kg complete feed. The FEEDAP Panel considered that the use level in water of clary sage oil is safe provided that the total daily intake of the additive does not exceed the daily amount that is considered safe when consumed via feed. The use of clary sage oil in animal feed under the proposed conditions of use is safe for the consumer and the environment. Regarding user safety, the essential oil under assessment should be considered as an irritant to skin and eyes and as a dermal and respiratory sensitiser. Since the oil of the flowering stems of S. sclarea is recognised to flavour food and its function in feed would be essentially the same as that in food, no further demonstration of efficacy was considered necessary.

Undernutrition disrupts jejunal and ileal microbiota and epithelial tissue homeostasis in a pregnant sheep model

Nutrition consistently affects microbe-host interactions in the gastrointestinal tract. This study aimed to unravel how undernutrition reshapes the microbial composition and the homeostasis of epithelium in the jejunum and ileum. Sixteen late-gestation Hu-sheep were randomly assigned to the control group (n = 8, 100% ad libitum feeding levels) or the undernutrition group (n = 8, which received 30% ad libitum feeding levels). After 15-d treatment, all ewes were slaughtered, and jejunal and ileal digesta and epithelium samples were collected for 16S rRNA gene sequencing and transcriptome sequencing, respectively. Results indicated that undernutrition decreased the jejunal and ileal tissue weights (P = 0.005 and P = 0.022) and the levels of volatile fatty acids (P = 0.019 and P = 0.007) and microbial protein levels (P = 0.019 and P = 0.031) in jejunal and ileal digesta. The relative abundance of acetate producing microbiota, including Clostridia UCG-014 norank, Ruminococcus, [Ruminococcus] gauvreauii, and Lachnospiraceae_Blautia, were significantly reduced (P < 0.05) in the jejunum and ileum. Undernutrition up-regulated (P < 0.05) the expression of genes involved in amino acid synthesis and fatty acid oxidation, but down-regulated (P < 0.05) the expression of genes associated with amino acid degradation, fatty acid synthesis, and extracellular structures in jejunal and ileal epithelium. In the jejunal epithelium, genes associated with extracellular matrix-receptor interactions, cell growth, and immune response were down-regulated (P < 0.05) upon undernutrition. Taken together, undernutrition changed the microbial community in the jejunum and ileum, which altered the fermentation mode and the production of volatile fatty acids and microbial protein. These affected the energy and protein system in the epithelium and reprogrammed substance metabolism and extracellular structures, which probably further influenced cell growth and immune response. These insights provide a foundation for completely clarifying the crosstalk between small intestinal microbiota and the host.

Short-term reduction in feed intake by dairy cows in the postpartum period leads to subclinical ketosis development

Subclinical ketosis is widespread in highly productive dairy cows after calving and often remains undiagnosed, leading to reduced productivity. Physiologically controlled feeding in the first weeks after calving and during the intensive lactation period can reduce the incidence of ketosis. The study aimed to determine how a short-term reduction of feed after calving affects the formation of ketone bodies in blood, urine and milk of dairy cows. The group of ten Ukrainian black-spotted dairy breed cows after calving aged from 4 to 6 years was involved in the experiment lasted for 72 h. In 24 h the amount of compound feed, haylage, and silage received by cows was gradually reduced until complete exclusion in the diet. Blood, urine, and milk samples were collected three times a day. The content of ketone bodies, β-hydroxybutyrate and glucose was estimated with the corresponding sets of indicator strips. The content of total bilirubin, cholesterol, albumin and enzymes activity in the blood serum were determined on biochemical analyzer. It was found that in 24 h after the beginning of feed reduction the level of blood glucose decreased, persistent hypoglycemia within 48 and 72 h was developed, the concentration of β-hydroxybutyrate in blood and milk and of ketone bodies in urine was elevated. The increase in total bilirubin concentration and liver enzymes activity in the blood serum with a simultaneous decrease in albumin level and delayed sodium propionate conversion into glucose were observed. Thus, short-term reduction in feed intake by dairy cows after calving causes ketosis development and violation of liver functions. Keywords: dairy сows, feeding level, glucose, ketosis, liver damage, β-hydroxybutyrate

Evaluating fructose content in poultry feed: electrochemical insights

AbstractThe global demand for poultry meat has increased, but consumers have become more picky in their nutritional choices. The fat content of poultry meat has risen since genetic advancement has resulted in higher rates of body weight gain and fat deposition, which are closely linked. The increase in further processing for fast-food poultry items has resulted in larger birds with more body fat. Usually, carbohydrates are used for easy weight gain in poultry. This study focuses on the electrochemical detection of fructose as a feed additive in poultry. The catalyst used was silver–silver oxide–zinc oxide (Ag–AgO–ZnO) and it was prepared by sol–gel method. Further, the surface morphology of the catalyst was analysed using various techniques, including X-ray diffraction, Fourier-transform infrared spectroscopy and transmission electron microscopy (XRD, FTIR and TEM). Cyclic voltammetry was carried out to find out the effectiveness of this catalyst in detecting fructose and our results revealed a sensitivity of 0.3 M with an electrochemical current of 1 mA cm−2, indicating the effectiveness of the chosen electrochemical approach. And further investigation was carried out to monitor effects of various parameters including scan rate, catalyst loading and fructose concentration. This research contributes valuable insights into assessing fructose levels in poultry feed, with potential implications for optimising nutritional formulations and enhancing overall poultry health. The electrochemical method demonstrates promise as a reliable tool for sensitively analysing fructose in feed additives. Precision and accuracy assessments further underscore the reliability of our electrochemical approach in differentiating fructose content within the poultry feed matrix. Graphical Abstract

Spatial distribution and risk assessment of perchlorate in raw cow milk from China

Perchlorate is a ubiquitous environmental contaminant worldwide, recognized as an emerging thyroid toxicant. This study focused on the pollution status, spatial distribution, possible sources of perchlorate in raw cow milk collected from 155 dairy farms in China, as well as the health risk of exposure to perchlorate through dairy products. The results showed that the detection rate of perchlorate in raw milk was 100% with the mean of 15.9 μg/kg, indicating the ubiquitous contamination of perchlorate in raw milk from China. The simulation of spatial distributions indicated that the levels of perchlorate in raw milk were spatially correlated, and relatively high levels of perchlorate exist in certain parts of Beijing-Tianjin-Hebei, Shanxi, Henan, and Zhejiang, suggesting potential environmental perchlorate contamination in these regions. A positive correlation was found between the perchlorate level in milk and the perchlorate level in feed, indicating the transfer process of perchlorate from feed to milk. The hazard quotient (HQ) values of exposure to perchlorate by dairy products ranged between 0 and 2.14, with the mean of 0.0188 and P95 of 0.101, indicating relatively low health risk to perchlorate through dairy products. To our knowledge, this is the first nationwide study on the spatial distribution and risk assessment of perchlorate in raw cow milk from China.

Effect of encapsulated Medinilla javanensis fruit extract on growth, protein digestibility and health of broilers

The study investigated the effect of encapsulated Medinilla javanensis fruit extract on performance, protein digestibility, and health of broilers. A total of 200 Cobb broiler chicks were divided into five treatments with four repetitions, including T0 (basal diet), T1 (basal diet + 200 mg/kg encapsulated Medinilla javanensis fruit extract), T2 (basal diet + 400 mg/kg encapsulated Medinilla javanensis fruit extract), T3 (basal diet + 600 mg/kg encapsulated Medinilla javanensis fruit extract), and T4 (basal diet + 800 mg/kg encapsulated Medinilla javanensis fruit extract). Sample collection was conducted on day 35 of age. Results showed that increased encapsulated Medinilla javanensis fruit extract levels in feed linearly increased (P&lt;0.05) body weight, body weight gain, intestinal lactic acid bacteria counts, protein digestibility and serum superoxide dismutase levels, while linearly decreasing (P&lt;0.05) feed conversion ratio, intestinal Escherichia coli counts, small intestinal pH values and serum malondialdehyde levels. In conclusion, encapsulated Medinilla javanensis fruit extract improved growth performance, protein digestibility intestinal health and antioxidant status of broilers. The encapsulated Medinilla javanensis fruit extract at a level of 600 mg/kg exerted the best performance and health of broilers.

Animal breeding and feeding tools may close human nutrition gaps

The last century has witnessed many innovations in agriculture and food technologies that have ensured the production of sufficient quantities of good hygienic food. Animal scientists have contributed substantially to efficient breeding and feeding practices by adapting animals for faster growth and improving feed efficiency and utilization. Breeding goals and feeding recommendations have been proposed with a primary focus on profitability to promote significant changes in the macronutrient content, i.e., animal body protein and fat reduction. However, improving the nutritional quality of meat was not included in the profit assessment. Increasing the lean meat fraction is consistent with the goal of public dietary guidelines for human nutrition proposed in 1980, emphasizing the importance of reducing the consumption of animal fat, particularly saturated fat. The application of breeding and feeding tools to modify and improve the fatty acid composition has been partly implemented in pigs and broiler chickens to supplement the dietary recommendations for humans. The health benefits of lean “red meat” have been questioned in recent years, with dietary guidelines and upper limits being introduced for human intake. Animal breeding indirectly reduces the total and heme iron (the redness generator) content in meat, due to covariation with priority breeding goals. Two micronutrients play important roles in the human diet and are derived largely from meat (selenium) and milk (iodine) if the amount provided and absorbed is sufficient and predictable. The iodine content can be highly dependent on the use of novel (more sustainable) feeds. The micronutrients discussed in this study (Fe, Se, I, and vitamin D) highlight opportunities for the utilization of breeding and feeding knowledge to adjust their levels to procure meat with a high nutrient density. The gaps in micronutrient levels in humans must be addressed by navigating within approved animal feeding levels. Animal scientists must recognize the nutritional impact of breeding and feeding and advertise them. In addition, human nutritionists must acknowledge the existing and potential changes in animal production to meet the dietary guidelines. Sustainable food production within the “One Health” concept can only be achieved through cooperation.

Dietary superdosing of phytase positively affects growth, mineral utilization and amino acid availability of channel catfish (Ictalurus punctatus)

The present study investigated the effects of supplementing high levels (superdosing) of dietary phytase on growth performance, mineral utilization and digestibility of amino acids in different regions of the gastrointestinal (GI) tract of fingerling channel catfish. The negative control (NC) diet was formulated with primarily soybean meal as a protein feedstuff which contributed 0.61 % total phosphorus (P) but was deficient in available P at 0.11 % of diet. Five other diets were formulated either with supplemental monocalcium phosphate at 1 % of diet in the positive control (PC), or supplemented with Quantum Blue phytase (AB Vista, Plantation, Florida) at 1000, 2000, 4000, or 8000 phytase units (FTU)/kg of diet. Groups of 20 catfish were each stocked into 24 aquaria operated as a closed, recirculating system with biological and mechanical filtration. All dietary treatments were assigned randomly to quadruplicate aquaria and initially fed at 6 % of total body weight per day. Feed quantities were adjusted weekly after weighing all fish in each aquarium as a group, and feeding levels were maintained close to apparent satiation throughout the 8-week feeding trial. Phytase supplementation significantly (P < 0.05) increased various responses of channel catfish including weight gain, feed efficiency, and protein retention compared to catfish fed the NC diet, resulting in values that were similar to catfish fed the PC diet. Moreover, catfish fed the phytase-supplemented diets had higher bone ash, calcium (Ca), magnesium (Mg), P, manganese (Mn), and zinc (Zn), as well as retention of Ca, Mg, P, iron (Fe), Mn, and Zn in whole-body tissues. Additionally, apparent availability of P from the posterior intestinal region increased with dietary phytase supplementation, with reduced excretion of nitrogen, Ca, Mg, P, copper (Cu), Mn, and Zn observed in comparison to fish fed the NC diet. Apparent digestibility coefficients for many of the indispensable and dispensable amino acids were increased by phytase supplementation, except for histidine, methionine, threonine, and taurine. This improvement in amino acid availability occurred only in the posterior region of the gastrointestinal tract. Channel catfish fed the diet containing 4000 FTU/kg diet had the highest postprandial plasma phosphorus level most of the time, except at 24 h after feeding. Based on these various responses, the optimal dietary phytase dosage was determined to average 5492 FTU/kg diet.

Metabolic changes in response to food intake in somatostatin 1.1 deficient zebrafish

Somatostatin is a multifunctional hormone with several genes in teleost fishes. A zebrafish CRISPR/Cas9 knockout of the somatostatin 1.1 (sst1.1) with persistent hyperglycaemia and hyperlipidaemia displayed reduced fecundity when fed brine shrimp ad libitum. Here, we investigated the effect of feeding brine shrimp one to three times a day on fecundity and liver transcriptomics of the sst1.1 mutant compared to their wild-type siblings to unravel molecular pathways associated with the phenotype. We find that the sst1.1 deficient zebrafish had high mortality when fed at the highest rate and that in both genotypes, growth and fecundity were proportional to food intake. Although glucose and cholesterol decreased substantially at the lowest level of feeding, they were still higher in the mutant than in the wild-type zebrafish. Furthermore, sst1.1 deficiency had a small but significant effect on the hepatic expression of protein, carbohydrate, and fatty acid biosynthesis genes, contributing to the mutant's diabetic phenotype.

Evaluating the Net Energy Requirements for Maintenance Based on Indirect Calorimetry and Heart Rate Monitoring in Gestating Sows

The objectives of this study were (1) to determine the net energy requirements for the maintenance of gestating sows based on indirect calorimetry, and (2) to explore the feasibility of predicting the net energy requirements for the maintenance of gestating sows based on daily heart rate monitoring. In Exp. 1, six Landrace × Yorkshire crossbred reproductive sows with an initial body weight of 229.5 ± 14.9 kg at d 56 of gestation were randomly assigned to six diverse energy feeding levels using a 6 × 6 Latin square design. The experimental diet was formulated using corn, soybean meal, and wheat bran as major ingredients, and the six feeding levels were set as 1.2, 1.4, 1.6, 1.8, 2.0, and 2.2 times metabolizable energy for maintenance (100 kcal ME/kg BW0.75·d−1), respectively. The animal trial lasted for six periods with 9 days per period, encompassing 5 days of adaptation, 3 days of calorimetry in fed state, and 1 day of calorimetry in fasting state. In Exp. 2, six Landrace × Yorkshire crossbred pregnant sows with an initial body weight of 232.5 ± 12.5 kg at d 64 were fed a corn–soybean meal diet. All sows were tested in a respiratory calorimetry chamber for a 4 day calorimetry test. The heat production of the gestation sows was measured every 5 min using indirect calorimetry, and the heart rate of the gestating sows was recorded every minute using a belt-shape monitor. The results showed that the net energy requirements for the maintenance of gestating sows significant increased as the gestational stage progressed (p &lt; 0.05), and a linear regression model revealed the average net energy requirement for the maintenance of gestating sows was 410 kJ/BW0.75 d−1 during late gestation (days 70–110). Moreover, the average heart rate of the gestating sows was 84 bpm, and the mathematical model developed to predict the net energy requirements for the maintenance of gestating sows was NEm(kcal/h)=19901+exp⁡[136−HR(bpm)43]. In conclusion, the average net energy requirement for the maintenance of sows during late gestation was 410 kJ/BW0.75 d−1, and the utilization of the heart rate monitoring method was found to provide a relevant, accurate prediction for the net energy requirements of sows.

Comparative Study of Fatty Acid Composition of Muscles of Atlantic Cod (Gadus morhua Linnaeus, 1758) with Natural Diet and Feeding near Salmon Farms

Coastal aquaculture and local fisheries interact in shared marine environments, influencing each other synergistically and/or antagonistically. Salmon farming, notably with open-net sea cages along the Norwegian coast, attracts wild fish due to increased food availability from uneaten feed, but it also exposes wild fish to farm emissions like waste and toxic chemicals (de-lice treatments, antifouling and medical agents). The attraction behaviour of wild fish can impact fatty acid composition in fish tissues, influenced by the high terrestrial fat content in salmon aquafeed. We study how the Atlantic cod, aggregating around salmon farms in a subarctic fjord in Northern Norway, can be affected, potentially altering their natural diet and fatty acid profiles. Our study compares the muscle-tissue fatty acid compositions of cod caught near aquaculture facilities (impact) versus fish caught in neighbouring fjords (control), and we hypothesise decreased omega-3 fatty acids near farms. The analysis revealed no significant differences in the fatty acid concentrations or categories between the impacted and control fish, challenging our initial expectations. However, differences were found for C18:1(n9)t (elaidic acid), with a higher value in the impacted fish. These findings suggest that salmon farming’s influence on cod’s fatty acid profiles in the flesh (i.e., relevant for the nutritional quality of the fillets that consumers eat) may be limited or minimal despite their aggregative behaviours around farms. The threshold levels of salmon feed consumed by wild cod before it affects the quality and survival of, e.g., sperm or other life stages, are not known and require new investigations. This study underscores the complexity of interactions between aquaculture and wild fisheries, impacting both ecological dynamics and consumer perspectives on seafood quality and health benefits.

Effects of different forms of amino acid supplementation on the performance and intestinal barrier function of laying hens fed a low-protein diet

The aim of this study was to investigate the effects of low-protein diets and the sustained release of synthetic amino acids (AA) on the performance, intestinal barrier function and nitrogen excretion of laying hens. Two hundred eighty-eight 39-week-old Hyline brown laying hens of were randomly divided into 3 groups with 8 replicates per group. The crude protein level in the control group (CON) was 16%, the crude protein levels in the crystal AA supplement group (LCP-CAA) and microencapsulated AA group (LCP-MAA) were both 13%, and the AA levels in the LCP-CAA and LCP-MAA groups were consistent with that in the CON group. The experiment lasted 12 wk, and production performance was assessed weekly. The FCR and ADFI values were significantly greater for the LCP-CAA group than for the CON and LCP-MAA groups (P < 0.05). Two hours after feeding, His levels were significantly greater in the LCP-CAA group than in the LCP-MAA group (P < 0.05); 4 h after feeding, the contents of Met, Thr, Leu and Val were significantly greater in blood from the LCP-MAA group (P < 0.05); 6 h after feeding, Trp, Ile and Arg levels were significantly greater in the LCP-MAA group (P < 0.05). The chylase content significantly decreased in the duodenum of the LCP-CAA group (P < 0.05), and the chylase and trypsin were contents increased in the ileum of the LCP-MAA group (P < 0.05). In the LCP-MAA group, significantly increased mRNA expression levels of Occludin, ZO-1 in duodenum; Occludin, ZO-1, y+LAT1 in jejunum; and ZO-1 in ileum were detected at 8 and 12 weeks (P < 0.05). The fecal nitrogen content significantly decreased in the low protein diet group (P < 0.01). In conclusion, reducing dietary crude protein levels and supplementing with microencapsulated AAs can improve intestinal barrier function, promote digestive enzyme secretion, increase the expression of AA transporters, improve dietary protein utilization efficiency, and reduce nitrogen emission in laying hens.

The relationship between aflatoxin M1 and immunoglobulin levels in cows' colostrum.

The purpose of the present research was to assess the amounts of aflatoxin M1 (AFM1) and immunoglobulin (IgA, IgG, and IgM) in cow colostrum samples, as well as their relationship. The sampling involved 90 cows (54 Montofon and 36 Simmental) from 15 independent farms. An appropriate number of samples from the total mixed ration (TMR) used in feeding the cows were collected simultaneously with the colostrum samples. AFB1 in feed, AFM1, and immunoglobulin (IgA, IgG, and IgM) levels in colostrum were evaluated using the ELISA method. The AFM1 level in colostrum samples exceeded the maximum allowed values for raw milk. Ig levels were higher in Montofon-breed cows' colostrum than in Simmentals. However, it was determined that neither the breed nor the lactation number significantly affected the colostrum Ig level. It was determined that there was no linear relationship between the number of lactations and immunoglobulin levels or between AFM1 and immunoglobulin levels in colostrum. Similarly, it was determined that there was no linear relationship between the AFB1 level in the feed and the AFM1 level in the colostrum of animals consuming these feeds.

Differences in Heating Temperature and Type of Phytase Enzyme on Enzyme Activity, Calcium and Phosphorus Levels in Complete Poultry Feed

Phytic acid is an antinutritional factor that can negatively affect livestock productivity by reducing the bioavailability of essential nutrients. Its content in feed ingredients can be minimized or even eliminated through various processing techniques, such as the addition of phytase enzymes. This study aimed to evaluate the effects of different heating temperatures and types of phytase enzymes on enzyme activity, calcium, and phosphorus levels in complete poultry feed. The research was conducted using a completely randomized design (CRD) with a factorial arrangement. The treatment consisted of two factors: factor A (phytase enzyme addition at three levels: no enzyme (0 FTU), commercial enzyme A (800 FTU), and commercial enzyme B (800 FTU), and factor B (heating temperature levels of 65°C, 70°C, 75°C, and 80°C). Each treatment combination was replicated three times. Data were analyzed using Minitab software, followed by Duncan's Multiple Range Test (DMRT) to determine significant differences between treatments at a 5% significance level. The results indicated that the addition of phytase enzymes significantly affected (P0.05) enzyme activity, calcium, and phosphorus levels in the feed. The best results for enzyme activity were observed with the treatment EAT3 (commercial phytase enzyme A at a heating temperature of 75°C), while the best results for calcium and phosphorus levels were achieved with treatment EBT3 (commercial phytase enzyme B at a heating temperature of 75°C).

Safety and efficacy of a feed additive consisting of an essential oil derived from leaves and terminal branchlets of Melaleuca alternifolia (Maiden & Betche) Cheel (tea tree oil) for use in all animal species (FEFANA asbl).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of tea tree oil obtained from leaves and terminal branchlets of Melaleuca alternifolia (Maiden & Betche) Cheel when used as a sensory additive for all animal species. The EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) concluded that tea tree oil was very unlikely to be of safety concern for long-living and reproductive animals and is of no concern for target species for fattening at the following concentrations in complete feed: 1.1 mg/kg for chickens for fattening, 1.5 mg/kg for turkeys for fattening, 1.7 mg/kg for laying hens, 2.0 mg/kg for piglets, 2.4 mg/kg for pigs for fattening, 3.1 mg/kg for sows, 5.0 mg/kg for veal calves (milk replacer) and salmonids, 4.4 mg/kg for cattle for fattening, sheep/goats and horses, 2.9 mg/kg for dairy cows, 1.8 mg/kg for rabbits, 0.9 mg/kg for cats, 5.3 mg/kg for dogs, 6.6 for crustaceans and 15 mg/kg for ornamental fish. These conclusions were extrapolated to other physiologically related species. For any other species, the additive is very unlikely to be of safety concern at 1.1 mg/kg complete feed. No concerns for consumers and the environment were identified following the use of the additive up to the highest safe use level in feed. Regarding user safety, tea tree oil should be considered as an irritant to skin and eyes and as a dermal and respiratory sensitiser. It is classified as a reprotoxic substance (category 1B) following CLP criteria and should be handled accordingly. Since M. alternifolia and its preparations were recognised to flavour food and its function in feed would be essentially the same as that in food, no further demonstration of efficacy was considered necessary.

Safety and efficacy of a feed additive consisting of an essential oil derived from the flowering tops of Thymbra capitata (L.) Cav. (Spanish type origanum oil) for use in all animal species (FEFANA asbl).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of an essential oil from the flowering tops of Thymbra capitata (L.) Cav. (Spanish type origanum oil) when used as a sensory additive in feed and in water for drinking for all animal species. The EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) concluded that the additive under assessment is considered safe up to the maximum use level in complete feed of 15 mg/kg for poultry species, 30 mg/kg for pigs and horses, 20 mg/kg for ruminants, 25 mg/kg for rabbits, dogs, cats and ornamental fish, and 125 mg/kg for salmonids. These conclusions were extrapolated to other physiologically related species. For any other species, the additive is safe at 15 mg/kg complete feed. The FEEDAP Panel considered that the use level in water for drinking is safe provided that the total daily intake of the additive does not exceed the daily amount that is considered safe when consumed via feed. The use of the additive in animal feed under the proposed conditions of use is safe for the consumer and the environment. Regarding user safety, the essential oil under assessment should be considered as an irritant to skin and eyes and as a dermal and respiratory sensitiser. Since T. capitata and its preparations were recognised to flavour food and its function in feed would be essentially the same as that in food, no further demonstration of efficacy was considered necessary.

Safety and efficacy of a feed additive consisting of an essential oil derived from the flowering tops of Lavandula angustifolia Mill. (lavender oil) for use in all animal species (FEFANA asbl).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of an essential oil from the fresh flowering tops of Lavandula angustifolia Mill. (lavender oil) when used as a sensory additive in feed and in water for drinking for all animal species. The EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) concluded that the additive under assessment is considered safe up to the maximum proposed use levels in complete feed of 30 mg/kg for dogs and ornamental fish. For the other target species, the calculated safe concentrations were 9 mg/kg for chickens for fattening, 13 mg/kg for laying hens, 12 mg/kg for turkeys for fattening, 19 mg/kg for pigs for fattening, 16 mg/kg for piglets, 23 mg/kg for sows, 39 mg/kg for veal calves (milk replacer) and salmonids, 35 mg/kg for cattle for fattening, sheep/goats and horses, 22 mg/kg for dairy cows, 14 mg/kg for rabbits and 7 mg/kg for cats. These conclusions were extrapolated to other physiologically related species. For any other species, the additive is safe at 7 mg/kg complete feed. The use of lavender oil in water for drinking was considered safe provided that the total daily intake does not exceed the daily amount considered safe when consumed via feed. The use of lavender oil in animal feed under the proposed conditions of use is safe for the consumer and the environment. Regarding user safety, the essential oil under assessment should be considered as an irritant to skin and eyes and as a dermal and respiratory sensitiser. Since the oil of the flowering tops of L. angustifolia is recognised to flavour food and its function in feed would be essentially the same as that in food, no further demonstration of efficacy was considered necessary.