Feeding Level Research Articles

Safety and efficacy of a feed additive consisting of a tincture derived from the flowers of Syzygium aromaticum (L.) Merr. & L.M. Perry (clove tincture) for 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 a tincture from the dried flower bud of Syzygium aromaticum (L.) Merr. & L.M. Perry (clove tincture) when used as a sensory additive in feed and water for drinking for all animal species. The product is a ■■■■■) solution, with a dry matter content of ~ 1.66%. The product contains on average 0.511% phenolic acids (of which 0.0344% were flavonoids), 0.039% eugenol, 0.00019% methyleugenol and 0.00008% estragole. The Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) concluded that the use of clove tincture is very unlikely to be of safety concern for the target species up to the maximum proposed use level of 50 mg clove tincture/kg complete feed for all animal species, except for horses, for which the proposed use level is 200 mg/kg complete feed. The FEEDAP Panel considers that the use in water for drinking alone or in combination with use in feed should not exceed the daily amount that is considered very unlikely to be of safety concern when consumed via feed alone. No safety concern would arise for the consumer and the environment from the use of clove tincture up to the maximum proposed use levels in feed. The additive under assessment should be considered as irritant to skin and eyes, and as a dermal and respiratory sensitiser. When handling the additive, exposure of unprotected users to methyleugenol and estragole may occur. Therefore, to reduce the risk, the exposure of the users should be minimised. Since the flower buds of S. aromaticum and their preparations were recognised to flavour food and their function in feed would be essentially the same, no demonstration of efficacy was considered necessary.

Safety and efficacy of a feed additive consisting of an essential oil derived from the leaves of Cymbopogon nardus (L.) Rendle (citronella 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 citronella oil obtained from the leaves of Cymbopogon nardus (L.) Rendle, 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 citronella oil from C. nardus is of low concern for long-living and reproductive animals at the use levels in complete feed of 3.5 mg/kg for laying hens and rabbits, 6 mg/kg for sows and dairy cows, 9.5 mg/kg for sheep/goats and horses, 2.0 mg/kg for cats and 10 mg/kg for dogs. For short-living animals (species for fattening), the additive was considered of no concern at concentrations of 18 mg/kg in chickens for fattening, 24 mg/kg in turkeys for fattening, 20 mg/kg for piglets, pigs for fattening, veal calves (milk replacer), cattle for fattening, sheep/goats for meat production, horses for meat production and rabbits for meat production, and 30 mg/kg for salmonids. The conclusions were extrapolated to physiologically related minor species. For any other species, the additive is considered of low concern at 2.0 mg/kg complete feed. The use of citronella oil in animal feed is expected to be of no concern for the consumers and for the environment. The essential oil under assessment should be considered as irritant to skin and eyes and as a dermal sensitiser. When handling the essential oil, exposure of unprotected users to methyleugenol may occur. Therefore, to reduce the risk, the exposure of the users should be minimised. Since the leaves of C. nardus 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.

Unraveling the important role of comammox Nitrospira to nitrification in the coastal aquaculture system.

Increasing nitrogen (N) input to coastal ecosystems poses a serious environmental threat. It is important to understand the responses and feedback of N removal microbial communities, particularly nitrifiers including the newly recognized complete ammonia-oxidizers (comammox), to improve aquaculture sustainability. In this study, we conducted a holistic evaluation of the functional communities responsible for nitrification by quantifying and sequencing the key functional genes of comammox Nitrospira-amoA, AOA-amoA, AOB-amoA and Nitrospira-nxrB in fish ponds with different fish feeding levels and evaluated the contribution of nitrifiers in the nitrification process through experiments of mixing pure cultures. We found that higher fish feeding dramatically increased N-related concentration, affecting the nitrifying communities. Compared to AOA and AOB, comammox Nitrospira and NOB were more sensitive to environmental changes. Unexpectedly, we detected an equivalent abundance of comammox Nitrospira and AOB and observed an increase in the proportion of clade A in comammox Nitrospira with the increase in fish feeding. Furthermore, a simplified network and shift of keystone species from NOB to comammox Nitrospira were observed in higher fish-feeding ponds. Random forest analysis suggested that the comammox Nitrospira community played a critical role in the nitrification of eutrophic aquaculture ponds (40-70 μM). Through the additional experiment of mixing nitrifying pure cultures, we found that comammox Nitrospira is the primary contributor to the nitrification process at 200 μM ammonium. These results advance our understanding of nitrifying communities and highlight the importance of comammox Nitrospira in driving nitrification in eutrophic aquaculture systems.

Occurrence of microplastics and metals in European seabass produced in different aquaculture systems: Implications for human exposure, risk, and food safety

Microplastics (MPs) are emerging contaminants of increasing concern as they may cause adverse effects and carry other contaminants, which may potentially compromise human health. Despite occurring in aquatic ecosystems worldwide, the knowledge about MP presence in different aquaculture systems and their potential impact on seafood products is still limited. This study aimed to determine the levels of MPs in water, feed, and European seabass (Dicentrarchus labrax) from three relevant aquaculture systems and estimate human exposure to MPs and metals through seabass consumption. The recirculating aquaculture system (RAS) had the highest MP occurrence in water and feed. MP levels in seabass followed the aquaculture system's levels in water and feed, with RAS-farmed fish presenting the highest MP load, both in the fish gastrointestinal tract (GIT) and muscle, followed by pond-, and cage-farmed fish. MPs' characteristics across aquaculture systems and fish samples remained consistent, with the predominant recovered particles falling within the MP size range. The particles were visually characterized and chemically identified by micro-Fourier Transform Infrared Spectroscopy (μFTIR). Most of these particles were fibres composed of man-made cellulose and PET. MP levels in GIT were significantly higher than in muscle for pond- and RAS-farmed fish, MPs' bioconcentration factors >1 indicated bioconcentration in farmed seabass. Metal concentrations in fish muscle were below permissible limits, posing low intake risks for consumers according to the available health-based guidance values and estimated dietary scenarios.

Survival and Development of in Vivo Produced Boran and Boran* Holstein Cross Embryos

One of biotechnology technique that is frequently used to enhance the number of animals with superior genetic ability and high productivity is embryo transfer. Embryos can be obtained in vivo or in vitro, and they can be frozen and then thawed before being delivered to the recipient animals. Conception rates are influenced by a number of variables, including the quality and developmental stage of the embryo, the location of the embryo's deposit in the uterus, the degree of difficulty of the transfer, whether to use a fresh or frozen embryo, the operator's experience, the corpus luteum's quality, whether to use a heifer or a cow, and the time of year the transfer occurs. The fertility of domestic animals is severely impacted by early embryonic death. For this reason, this study was carried out to gather data on early embryonic development that is normal, the amount and timing of embryonic mortality, potential endogenous and exogenous causes of embryonic loss, and to develop strategies to lower embryonic mortality. A total of 40 embryos (20 fresh and 20 frozen, 26 quality grade 1 and 14 quality grade 2, 29 compact Morula stage and 11 early Blastocyst stage) were transferred to 40 recipient cows (22 Boran and 18 H-B cross) with different body condition score. Return to heat was used as method of pregnancy diagnosis and all recipients were followed around day 14 post embryo transfer and 14 animals were shown heat sign, the rest 26 animals were suspected for pregnancy (65%). Using ultrasound, a pregnancy diagnosis was made on day 45, and 20 recipient animals were found to be 50% positive for PD. On day 60, PD positive animals were re-examined with ultrasound and only 10 were confirmed as PD positive (25%). The PD negative on day 45 and day 60 were suspected to be early embryonic mortality. Other pregnancy loss occurred in this study was abortion nearly after five month of pregnancy. It is not doubtful that, the technique of embryo transfer is utilized to increase the reproductive rates of important female animals. However, it needs proper management for both donor and recipient animals. Therefore, for the successful application of the technology optimum level of feeding both quantity and quality, health management and conducive environment should be fulfilled for all animals.

Use of a precision feeding program during gestation improves the performance of high-producing sows

Current gestating sow feeding strategies are based on using a single diet regardless of parity or gestation stage. Precision feeding (PF) of the individual sows allows dynamic changes in amino acid and energy requirements throughout gestation. The hypothesis of the study was that meeting the daily predicted amino acid and energy demands of gestating sows using a mathematical model and automatic precision feeder to establish the nutrition programs, would improve reproductive and productive performance compared to conventional feeding programs. Seventy-five mixed-parity sows were distributed among 3 treatments. A treatment managed as flat curve (FLAT: 2.1 kg/d, 1 – 110 d), a high-low-high curve (HLH: 2.2 kg/d, 1 – 49 d; 2.0 kg/d, 50 – 84 d; 2.6 kg/d, 85 – 110 d), where sows received the same diet with 3.2 Mcal/kg of metabolizable energy (ME) and 0.7 g/kg of standardized ileal digestible (SID) lysine. For the PF treatment, feeding level and blend of 2 basal diets (3.0 Mcal/kg of ME; 8.0 and 2.0 g/kg of SID lysine for high and low lysine, respectively) was adjusted daily for each sow to accurately meet estimated amino acid and energy requirements based on live weight, gestation stage and parity. Sows fed PF were heavier on d 110 of gestation (P = 0.011) and tended to increase total number of born (P = 0.092) and born alive (P = 0.077). Sows fed PF showed a higher litter weight (P = 0.003) at birth, lower lactation feed intake (P = 0.010), higher milk yield (P = 0.043) and a larger litter size (P = 0.050). Precision feeding sows also presented an improved maternal transformation index (P = 0.013) when compared to HLH and FLAT. In conclusion, our results demonstrate that the application of PF strategies based on daily nutrient adjustments is highly beneficial for high-producing sows to support the dynamic needs for nutrient availability for the sow´s body growth, mammary gland and fetal development.

Some plasma biomarkers of residual feed intake in beef cattle remain consistent regardless of intake level

This study investigated whether plasma biomarkers of residual feed intake (RFI), identified under ad libitum feeding conditions in beef cattle, remained consistent during feed restriction. Sixty Charolais crossbred young bulls were divided into two groups for a crossover study. Group A was initially fed ad libitum (first test) and then restricted (second test) on the same diet, while Group B experienced the opposite sequence. Blood samples were collected from the 12 most divergent RFI animals in each group at the end of the first test and again after the second test. 12 plasma variables consistently increased, while three consistently decreased during feed restriction (FDR < 0.05). Only two metabolites, α-aminoadipic acid for Group A and 5-aminovaleric acid for Group B, were associated with RFI independent of feed intake level (FDR < 0.05), demonstrating moderate-to-high repeatability across feeding levels (intraclass correlation coefficient ≥ 0.59). Notably, both metabolites belong to the same metabolic pathway: lysine degradation. These metabolites consistently correlated with RFI, irrespective of fluctuations in feed intake, indicating a connection to individual metabolic processes influencing feed efficiency. These findings suggest that a portion of RFI phenotypic variance is inherent to an individual’s metabolic efficiency beyond variations in feed intake.

Safety and efficacy of a feed additive consisting of an essential oil derived from fresh leaves of Melaleuca cajuputi Maton & Sm. ex R. Powell and Melaleuca leucadendra (L.) L. (cajuput oil) for use in all animal species (FEFANA asbl).

Following a request from the European Commission, the EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on the safety and efficacy of cajuput oil obtained from fresh leaves of Melaleuca cajuputi Maton & Sm. ex R. Powell and Melaleuca leucadendra (L.) L., when used as a sensory additive for all animal species. The FEEDAP Panel concluded that cajuput oil is safe up to the maximum proposed use levels in complete feed of 30 mg/kg for sows and dogs, 50 mg/kg for horses and ornamental fish, 40 mg/kg for salmon and 5 mg/kg for cats. For the other species, the calculated safe concentrations were 18 mg/kg for chickens for fattening, 26 mg/kg for laying hens, 23 mg/kg for turkeys for fattening, 37 mg/kg for pigs for fattening, 31 mg/kg for piglets, 78 mg/kg for veal calves (milk replacer), 69 mg/kg for cattle for fattening and sheep/goats, 45 mg/kg for dairy cows and 28 mg/kg for rabbits. These conclusions were extrapolated to other physiologically related species. For any other species, the additive is safe at 5 mg/kg complete feed. The use of cajuput 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. No concerns for consumers and the environment were identified following the use of the additive up to the highest safe use level in feed. The essential oil under assessment should be considered as an irritant to skin and eyes, and as a dermal and respiratory sensitiser. Since cajuput oil was recognised to flavour food and their 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 a dry extract obtained from the leaves of Ginkgo biloba L. (ginkgo extract) for horses, dogs, cats, rabbits and guinea pigs (FEFANA asbl).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of a feed additive obtained from the dried leaves of Ginkgo biloba L. (ginkgo extract) when used as a sensory additive in feed for horses, dogs, cats, rabbits and guinea pigs. Ginkgo extract contains ≥ 24% total flavonoids, ≥ 6% total terpene lactones and ≤ 1 mg/kg ginkgolic acids. The EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) concluded that ginkgo extract is safe for the target species at the following concentrations in complete feed: 2.8 mg/kg for horses and cats, 1.1 mg/kg for rabbits and guinea pigs, and 3.3 mg/kg for dogs. No safety concern would arise for the consumers from the use of ginkgo extract up to the highest level in feed which is considered safe for food-producing species (horses and rabbits). The additive should be considered as irritant to skin and eyes, and as a dermal and respiratory sensitiser. The use of the additive at the proposed level in feed for the target species is not considered to be a risk to the environment. While the available data indicate that Ginkgo preparations have a distinctive flavour profile, there is no evidence that the ginkgo extract would impart flavour to a food or feed matrix. Therefore, the FEEDAP Panel cannot conclude on the efficacy of the additive.

Safety and efficacy of a feed additive consisting of a tincture derived from the dried fruit of Schisandra chinensis (Turcz.) Baill. (omicha tincture) for poultry, horses, dogs and cats (FEFANA asbl).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of a tincture from the dried fruit of Schisandra chinensis (Turcz.) Baill. (omicha tincture), when used as a sensory additive in feed for horses, cats, dogs, and in feed and in water for drinking for poultry. The product is a water/ethanol (55:45 v/v) solution, with a dry matter content of not more than 4% (w/w) and a content of 0.01%-0.15% (w/w) for the sum of schisandrin and deoxyschisandrin. The Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) concluded that omicha tincture is safe at the following concentrations in complete feed: 16 mg/kg for turkeys for fattening, 12 mg/kg for chickens for fattening and other poultry for fattening or reared for laying/reproduction, 18 mg/kg for laying hens and other laying/reproductive birds, 56 mg/kg for dogs and 47 mg/kg for horses and cats. The additive is considered safe for consumers when used up to the highest safe level in feed for poultry species and horses. Omicha tincture should be considered as irritants to skin and eyes, and as dermal and respiratory sensitisers. The use of omicha tincture as a flavour in feed for poultry species and horses was not considered to be a risk to the environment. Since it was recognised that the fruit of S. chinensis can influence sensory properties of feedingstuffs, no further demonstration of efficacy was considered necessary for the tincture under assessment.

Mетаболічна та продуктивна дія удосконалених за складом БВМД у раціонах годівлі молодняка овець

The article presents the results of the study of productive and metabolic effect of the use of a protein-vitamin-mineral supplement (PVMS), an improved formulation, as part of the feeding rations of young repair ewes of the Ukrainian mountain-Carpathian breed in the conditions of the natural-climatic zone of the Carpathian foothills, by introducing into their composition local highly nutritious feed components. The research was carried out during a two month period (February – March) in the conditions of the Radvan-Nova farm (Myloshevychi village, Pustomytivskyi district, Lviv region) on young ewes of the above breed in the winter-spring stall period. For this purpose, three groups of 12-month-old young ewes of 10 heads in each group (control and two experimental) were formed by the method of analogues, which were kept separately with the provision of proper care and level of feeding. The feeding ration consisted of meadow grass-herbaceous hay (unlimited), oat-pea straw (unlimited) and compound feed. The calves of the control group received 0.4 kg of standard compound feed according to the recipe of the ITSR named after M. F. Ivanov "Askania-Nova", the young ewes of the first experimental group – the same amount of experimental compound feed, the young ewes of the second experimental group – 0.3 kg of a mixture of whole grains of oats, barley, corn and 0.1 kg of experimental PVMS. The conducted studies established that, in the conditions of the indicated climatic zone, feeding of 12-14-month-old young ewes with the rations of compound feed and PVMS including local feed ingredients in their composition, compared to standard analogues, provides an increase in indicators of weight and linear growth of animals, a decrease in monetary expenditure on increases in live weight, improves biochemical indicators of metabolism in the blood. It is also shown that the use of compound feed and PVMS of an improved recipe compared to standard feed, when growing repair young ewes of the Ukrainian mountain-Carpathian breed aged 12–14 months in the winter-stall period makes it possible to reduce monetary costs for obtaining 1 t of growth gain by 10–13%

Seasonal variation of mycotoxin levels in poultry feeds and feed ingredients in Oyo State, Nigeria.

Mycotoxins pose a major problem to poultry production as a result of feed contamination which has deleterious consequences such as production losses and human health risks. A total of 158 chicken feed samples were randomly collected from 46 consenting poultry farms in Oyo State throughout the wet season (April-October; 91 samples) and the dry season (November-March; 67 samples), including compounded feed (n = 129) and feed ingredients (n = 29). Samples were promptly transported to the laboratory in sterile plastic vials for lateral flow assay for mycotoxins using six different commercial mycotoxin test kits each for aflatoxin B1, zearalenone, deoxynivalenol, ochratoxin A, fumonisin, and T-2 toxin/HT-2 toxin. Summary values of mycotoxin levels (µg/kg) in the feedstuffs were represented as frequency or median (and range). Fisher exact or Mann-Whitney U tests were carried out where appropriate at α = 0.05. Every sample contained at least four mycotoxins. Aflatoxins and fumonisin co-occurred in 80% of the samples. Aflatoxin and fumonisin concentrations were above the permissible limits in 32.9% and 18.4% respectively in feedstuff sampled in the dry season while the values were 17.1% and 6.3% respectively during the wet season. Among feed ingredients, peanut cake and maize had the highest median concentration of aflatoxin and fumonisin, respectively. Median aflatoxin concentration in the feedstuff was significantly higher than the permissible limit irrespective of season. There is a need to frequently monitor mycotoxin levels of feed and feed ingredients and improve storage system for feed ingredients in order to reduce the risk associated with high mycotoxin intake in poultry.

Feed Type and Level of Viterna on Body Weight, Percentage of Carcass, Non-Carcass and Abdominal Fat of Broiler Chickens

This study aims to examine the effects of different types of feed and level of viterna on the final body weight, carcass percentage, non-carcass, and abdominal fat of broiler chickens. The method used was a 2x4 factorial Completely Randomized Design. The first factor was 2 types of commercial feeds (J1=A and J2=B). The second factor was 4 levels viterna (P0=0cc; P1=1.5cc; P2=3cc; P3=4.5cc/l drinking water). There were 8 treatment combinations with 4 replications, and each replicate consist of 4 chickens, a total of 128 broilers was used. The treatment combinations were as follows: J1P0=feed A without viterna in drinking water, J1P1= feed A+1.5cc viterna/l water, J1P2 = feed A+ 3cc viterna/l water, J1P3= feed A + 4.5cc viterna/l water, J2P0 = feed B without viterna in drinking water, J2P1= feed B + 1.5cc viterna/l water, J2P2=feed B + 3cc viterna/l water, J2P3= feed B + 4.5cc viterna/l water. The measured variables were final body weight, carcass percentage, non-carcass, and abdominal fat. Data were analyzed using a variance test at a significance level of 5%, treatments that were significant (P≤0.05) followed by the Duncan Multiple Range Test. The results showed that there was no interaction (P&gt;0.05) between feed type and viterna level on all parameters. In conclusion, differences in the type of feed, and viterna level, also interaction between the two factors did not make a difference to the final weight, percentage of carcass, non-carcass, and abdominal fat of broiler chickens.

Root‐zone enrichment of soil organic carbon and nitrogen under grazing and other land uses in a humid‐temperate region

AbstractGrazing lands can be considered a conservation land use providing value to farmers and society. An underappreciated value of these lands may be in C and N storage and cycling. However, soil organic C (SOC) and total soil N (TSN) storage under humid‐temperate zone pastures have not been well characterized. A survey of 31 farms in Virginia USA characterized SOC and TSN depth distributions under a diversity of grassland management scenarios, as well as in comparison with long‐term no‐till cropland and woodland uses on the same farms. Root‐zone enrichment calculations separated management‐controlled SOC and TSN stocks from a baseline condition characterized at 30‐cm depth. Total stock of SOC at 0–30‐cm depth varied from 46 to 88 Mg C ha−1 (5%–95% range from 304 soil profiles) across all land uses. Root‐zone enrichment of SOC was maximized under mature pastures (≥20 years old) at 38.3 ± 1.6 Mg C ha−1, which was not different from that under woodland (39.8 ± 1.2 Mg C ha−1), but was greater than under no‐till cropland (28.3 ± 1.3 Mg C ha−1) and conventional‐till cropland (15.1 ± 5.1 Mg C ha−1). Root‐zone enrichment of TSN was optimized at stocking rate of ~1 Mg live weight ha−1, but was not affected by stocking method, N fertilization history, or low levels of hay feeding. These results suggest that grazed pastures in Virginia are storing significant amounts of SOC and TSN, with at least half due to management‐induced compared with pedogenic‐controlled accumulation.

Knockout of lws1 in zebrafish (Danio rerio) reveals its role in regulating feeding and vision-guided behavior.

Long-wave sensitive (LWS) is a G protein-coupled receptor expressed in the retina, and zebrafish is a better model organism for studying vision, but the role of LWS1 in vision-guided behavior of larvae fish has rarely been reported. In this study, we found that zebrafish lws1 and lws2 are tandemly replicated genes, both with six exons, with lws1 being more evolutionarily conserved. The presence of Y277F in the amino acid sequence of lws2 may have contributed to the shift of λmax to green light. We established a lws1 knockout zebrafish model using CRISPR/Cas9 technology. Lws1-/- larvae showed significantly higher levels of feeding and appetite gene (agrp) expression than WT, and significantly lower levels of anorexia gene (pomc, cart) expression. In addition, green light gene compensation was observed in lws1-/- larvae with significantly increased expression levels of rh2-1. The light-dark movement test showed that lws1-/- larvae were more active under light-dark transitions or vibrational stimuli, and the expression of phototransduction-related genes was significantly up-regulated. This study reveals the important role of lws1 gene in the regulation of vision-guided behavior in larvae.

Effect of pre-and post-partum feed supplementation of Maraz does on the productive performance of their offspring

The purpose of this experiment was to investigate the impact of maternal pre-and post-partum feed supplementation, under farm conditions, on goat kid's growth, follicle traits and fiber production. The design of experiment was supplementation from 2 months pre-partum to 2 months post-partum with 3 nutritional groups (8 does each). The first does group (GI) was fed black barley at 250 g/doe/day (traditional farmer’s practice), whereas does of the second (GII) and third (GIII) groups were fed concentrate diet at 500 and 750 g/doe/day, respectively. Results revealed that birth weight from GII and GIII was significantly (P&lt;0.05) higher by 22% (2.3 vs. 1.8 kg) than that of GI. Weaning weight and marketable live weight traits, growth rates, follicle traits except primary follicles, and fiber characteristics were significantly (P&lt;0.05) higher in (GIII) followed by (GII) and then (GI). Moreover, goat kids of the GIII attained significantly (P&lt;0.05) 37% (16.9 vs. 10.7 kg) and 26% (16.9 vs. 12.5 kg) more marketable live weight compared with GI and GII, respectively. Also, goat kids of the GIII produced 32% (813.3 vs. 553.3 g; P&lt;0.05) and14% (813.3 vs. 703.3 g; P&gt;0.05) higher fleece weight than that of GI and GII, respectively. Additionally, body weight traits, growth rates, and fiber characteristics were significantly (P&lt;0.05) affected by sex of birth. In conclusion, supplementation with an increased level of feeding concentrate pre-and post-partum of Maraz goats showed a significant (P&lt;0.05) positive effect on productive performance of their kids in comparison to the traditional farmer’s practice.

Bean Sprouts, Lettuce, and Milk as Water Sources in Tenebrio molitor Larval Growth.

The Tenebrio molitor larva (yellow mealworm) holds great potential as a sustainable ingredient in food and feed. Optimizing its growth under mass farming requires careful water management. However, the availability and cost of fresh fruit and vegetables, which are the most widely used sources of water, can vary geographically, which calls for the search for relatively affordable, effective, and readily available alternatives. We evaluated the effect of three water sources (bean sprouts, lettuce leaves, and milk) as well as their quantity on weights and nutrient profiles of reared T. molitor larvae. Newly hatched mealworm larvae were maintained in controlled conditions of 25 °C and 60% relative humidity under a 12-h light-dark cycle for 15 weeks. When provided as sole-supplements, bean sprouts induced the highest larval weight gains compared to fresh lettuce leaves, which in turn performed better than milk and water. However, the addition of milk to the vegetable supplements enhanced growth. Furthermore, doubling the level of water supply resulted in 70% higher larval weights by week 14 post hatching. Moreover, water sources did not change the nutrient content of the harvested larvae. These findings suggest that mealworm productivity can be enhanced by increasing water feed levels and that bean sprouts may be a superior alternative to lettuce.

Performance evaluation of coated tool in end milling of XH67MBTHO alloy

ABSTRACT XH67MBTHO is a promising nickel-based alloys which finds applications in aerospace engineering due to its exceptional hot hardness, corrosion resistance and strength at superior temperatures. However, due to its weak thermal conductivity(k=13.4W/mK) and high tendency to work harden, XH67MBTHO exhibits poor machinability. Therefore, the major objective of this study is to investigate the machinability characteristics of XH67MBTHO, using TiAlN coated milling inserts at three levels of speed, feed, and axial depth of cut. Significant parameters affecting responses were identified using ANOVA. SEM and EDS analysis of worn-out tool shows delamination, adhesion, abrasion and diffusion were major tool wear mechanism. Also, as machining conditions shift from higher to lower, tool life increases to 1200 seconds from 49.18 seconds and surface roughness decreases from 0.52 µm to 0.18 µm respectively. Also, a regression and Artificial Neural Network model were developed to predict the process response in terms of input parameters.

133 Effects of supplementing corn silage to fall-calving heifers and cows grazing bermudagrass on cow and calf performance and physiology

Abstract The objective was to test the effect of supplemental feeding of corn silage to cows grazing bermudagrass pastures on cow and calf performance and physiology. In a completely randomized design, multiparous and primiparous Angus-crossbred cows (n = 24) grazed bermudagrass pastures assigned to one of two levels of supplemental feeding (non-supplemented or supplemented at 1% of BW on a DM basis of corn silage) during the growing season. Each replicate (pasture, n = 4 per treatment) was stocked with 3 cows. Cows averaged 155 ± 14 d of gestation at trial initiation. Cows were fed corn silage (38% DM, 7.83% CP DM basis) daily in fenceline bunks, and supplementation rate was adjusted throughout the trial to maintain 1% of BW. Cows were weighed on two consecutive days at both initiation and conclusion of the trial and cows were maintained on similar diets for 4 d prior to collecting weights to minimize variation in ruminal fill. Body weight (BW), body condition score (BCS), hair score (HS), hair length (HL), and rump fat (RF) measurements were collected at initiation (the middle of the second trimester), trial mid-point (beginning of third trimester), and approximately 2 wk before estimated parturition. Cows were removed from experimental pastures upon trial conclusion and relocated to calving pastures consisting of tame grasses (&amp;gt;65% bermudagrass). Data were analyzed as a mixed model with pasture as experimental unit and cows within pasture as subsamples. Cows began the trial at an average BW of 549 ± 22 kg (SEM) and an average BCS of 5.2 ± 0.17 (SEM). Supplementation of second and third trimester pregnant cows on bermudagrass did not influence BW gain, BCS, HS, or HL (P &amp;gt; 0.27). Rump fat tended (P = 0.15) to be increased with supplemental feeding. Supplemental feeding of corn silage on warm season perennial grass during the growing season did not appear to impact late gestation cow performance at the level fed in this study.

165 Does supplementation of beef cattle impact the agronomy performance of tall fescue and bermudagrass pastures?

Abstract In forage-based beef cattle systems, bermudagrass [Cynodon dactylon (L.) Pers.] and tall fescue (Festuca arundinacea Schreb.) stand as widely used forage species. The strategic supplementation of animals may reduce forage intake, thereby potentially affecting the agronomic performance of these grasses. Our objective was to evaluate the impact of beef cattle supplemental feeding on forage accumulation, forage mass, and nutritive value in tall fescue and bermudagrass pastures. Two studies were conducted where pregnant beef cows were supplemental fed 1% of BW on DM basis of corn silage daily (SUP) or received no supplemental feeding (free-choice mineral; NON). Trial 1: conducted on bermudagrass pastures (BERM) grazed from late May to early October. Experimental design for BERM was completely randomized design with 4 pastures per treatment (n = 3 cows/pasture; average 5 years of age; 550 ± 72 kg initial BW). Trial 2: conducted on fescue pastures (FES) with an experimental design of a 2 x 2 factorial arrangement. The two factors evaluated were fescue type [TOXIC (507 ppm ± 0.82 SEM ergot alkaloids; 92.5% endophyte infection)] or non-toxin-producing (NT; 5 ppm ± 2.50 SEM ergot alkaloids; 38.6% endophyte infection) and two levels of supplemental feeding (NON or SUP). There were 3 or 4 replications per fescue x supplemental feeding treatment (n = 15 pastures), stocked with 3 cows/pasture (average age 4.75 years; 558 ± 73 kg initial BW) and grazed from early May through November. Forage accumulation (FA) was estimated every 28 d using the paired-cage method (4 exclosure cages/pasture). On each exclusion period, the forage mass (FM) was estimated both inside and outside the cages through destructive sampling method and samples analyzed for forage quality. Pasture was experimental unit and repeated measures were included in analysis. Bermudagrass FM tended to be increased by 31% with SUP (P = 0.09; 774 kg/ha greater). Forage accumulation tended (P = 0.07) to be affected by feeding method x month. There was greater FA in June for SUP; however, there was greater FA for NON in July. SUP pastures had greater ADF (1% more; P = 0.01) and reduced TDN (1.5%; P &amp;lt; 0.01) than NON. Forage mass tended to be 10% greater for TOXIC pastures (P = 0.09; 409 kg/ha more forage mass). Supplemental feeding on fescue did not impact FM (P = 0.74). Forage accumulation was not impacted by fescue type, feeding method, nor the interaction (P &amp;gt; 0.30). Cows generally do not consume as much toxic fescue, thus more forage is available in pastures and supplemental feeding did not alter forage parameters. However, on a warm-season grass that is growing while supplemental feeding, forage availability was increased and maybe useful as method to increase stocking rates or as mitigation tool during drought.