Automatic Feeding System Research Articles

Growth, health, and economics of dairy calves fed organic milk replacer or organic whole milk in an automated feeding system

The objective of the study was to investigate the growth, health, behavior, and economics of dairy calves fed organic milk replacer (n = 41) or organic whole milk (n = 40) in an automatic feeding system. Calves were fed either organic milk replacer or whole milk (assigned to treatment in birth order) during 2 seasons from March to July 2018 and from September to December 2018 at the University of Minnesota West Central Research and Outreach Center in Morris, Minnesota. The treatment groups were (1) pasteurized whole milk fed at 13% total solids of organic milk (WM), or (2) milk replacer fed at 150.98 g of dry replacer powder per liter of water (MR). Milk replacer was fed at 14.65% total solids based on the manufacturer's recommendation. Calves were introduced to the automated feeder at 5 d and allowed to drink up to 8 L/d at the maximum allowance. At 50 d, the allowance was reduced by 0.2 L/d and calves were weaned at 56 d. Milk feeding behavior (feeding station visit behaviors and drinking speeds) were collected from the automatic feeding system and analyzed by feeding group. Body weights were recorded at birth and then weekly until weaning (56 d). Health scores of calves were recorded twice a week. Data were analyzed using PROC MIXED (SAS Institute Inc.). Independent variables for analyses were the fixed effects of breed group, season of birth, and treatment group, and the interaction of season and treatment group along with pen as a random effect. No differences were found between treatment groups for average daily gain, weaning weight, hip height, or heart girth. Milk feeding behavior varied between the 2 feeding treatment groups. The WM calves had shorter visits to the feeding station (2.44 vs. 3.01 min, respectively) compared with MR calves. Overall drinking speeds of the WM calves were higher (1,301 mL/min) than those of the MR calves (581 mL/min). The MR calves had higher fecal scores than WM calves. The average cost per kilogram of gain was lower for WM calves ($6.35/kg) compared with MR calves ($8.82/kg). The results of this study indicate health and economic advantages to feeding organic dairy heifer calves whole milk during the preweaning period.

Prototype Sistem Pakan Ikan dan Pemantauan PH Berbasis Android dengan Metode PLC

Abstract
 During the pandemic of covid-19, betta fish cultivation is one of the income alternatives. It makes the cultivation of betta fish is increasing. However, not all cultivators can successfully cultivate betta fish. Water quality and fish feed must be maintained in order for betta fish can grow perfectly and attractive. The problems that often encountered to the betta fish cultivator is about feeding and monitoring pH levels, which is still manual. This is can failure in betta fish cultivation of the cultivators are not disciplined. To minimize it, then will be made “Prototype Fish Feeding System and PH Monitoring Based Android”. This research is used PLC method: (a) Requirements Analysis, (b) Design, and (c) Implementation. Divided into 2 functions: Automatic Betta Fish Feeding System Based Android Function using Node MCU ESP8266 and Monitoring PH Levels Function using Arduino Uno. The result from this research is the user can control the open and close feed on the servo through an android application, the system can provide a distance of the feed supply to a user in real-time by notifications, the LCD always display pH value, the buzzer provides a sound when the water quality has reached the acid or alkaline index.

Lying Behaviour in Dairy Goats: Effects of a New Automated Feeding System Assessed by Accelerometer Technology.

Simple SummaryGoat farming is becoming more important in Germany and as dehorning is forbidden, it is necessary to facilitate animal welfare among horned and mixed-horned herds. In this study an optimized automatic concentrated feeding system was installed in a mixed-horned herd and lying behaviour was detected by accelerometer technology. Results show a seasonal progression of lying behaviour in dairy goats and an adjustment of behavioural differences between horned and hornless goats with the new feeding system.The aim of this study was to evaluate lying behaviour in dairy goats before and after installation of an optimized automatic concentrated feeding system (AFS). A mixed-horned herd of Bunte Deutsche Edelziege was used. As many agonistic interactions between goats happen at the feeding place, a new automated feeding system was installed to better fulfil the needs of horned goats. Lying behaviour is an indicator to ascertain animal welfare of ruminants. In order to measure lying behaviour accelerometer technology was used and verified by video analyses. The results show an agreement of 99.62–99.93% per lying time by comparing accelerometers to video data. Over all goats, a mean ± SD lying time (LT) of 11.78 ± 1.47 h/d, a mean ± SD lying bout duration (LBD) of 0.51 ± 0.10 h/bout and a mean ± SD frequency of lying bouts (FLB) of 24.35 ± 5.57 were found. Lying behaviour follows a seasonal progression with significant lowest LBD and highest FLB in summer. With the old AFS significant differences in LBD and FLB were detected between horned and hornless goats, but with the new AFS results were adjusted. Findings suggest that changes in feeding management do not affect the general seasonal progression of lying behaviour but can affect the behavioural differences between horned and hornless dairy goats.

A Basic Study on Establishing the Automatic Sewing Process According to Textile Properties

This study aimed to establish an automatic sewing process for garment production according to textile properties. An automatic feeding system and a self-made template were introduced to an industrial sewing machine. Two types of stitches were performed on fabrics with various physical properties and surface roughness using this automatic sewing machine. The appearance, stitch length and width, seam strength, and seam efficiency were evaluated according to the sewing conditions, such as presser height and sewing speed. In addition, the correlation between textile properties, sewing conditions, and sewability was analyzed to derive a regression equation for sewability. The evaluation showed no difference in the lock stitch condition. On the other hand, under the zigzag stitch condition, the stitch width differed according to the presser height, which also affected the seam structure. The optimal presser height for each fabric was derived from the experimental results. In terms of the sewing speed, however, the seam strength was the best at 200 RPM in the lock stitch and 400 RPM in the zigzag stitch. The moderating effect of the presser height between textile properties and sewability in the lock stitch condition was confirmed. This result can be used as basic data for establishing an automatic sewing process for smart factories.

Eco-Friendly Feed Formulation and On-Farm Feed Production as Ways to Reduce the Environmental Impacts of Pig Production Without Consequences on Animal Performance.

Animal feeding has a major contribution to the environmental impacts of pig production. One potential way to mitigate such effects is to incorporate an assessment of these impacts in the feed formulation process. The objective of this study was to test the ability of innovative formulation methodologies to reduce the impacts of pig production while also taking into account possible effects on growth performance. We compared three different formulation methodologies: least-cost formulation, in accordance with standard practices on commercial farms; multiobjective (MO) formulation, which considered feed cost and environmental impacts as calculated by life cycle assessment (LCA); and MO formulation, which prioritized locally produced feed ingredients to reduce the impact of transport. Ninety-six pigs were distributed between three experimental groups, with pigs individually weighted and fed using an automatic feeding system from 40 to 115 kg body weight. Based on the experimental results, six categories of impacts were evaluated: climate change (CC), demand in non-renewable energy (NRE), acidification (AC), eutrophication (EU), land occupation (LO), and phosphorus demand (PD), at both feed plant gate and farm gate, with 1 kg of feed and 1 kg of live pig as functional units, respectively. At feed level, MO formulations reduced CC, NRE, AC, and PD impacts but sometimes increased LO and EU impacts. These formulations reduced the proportion of cereals and oil meals into feeds (feed ingredients with high impacts), while the proportion of alternative protein sources, like peas, faba beans, or high-protein agricultural coproducts increased (feed ingredients with low impacts). Overall, animal performance was not affected by the dietary treatment; because of this, the general pattern of results obtained with either MO formulation at farm gate was similar to that obtained at feed level. Thus, MO diet formulation represents an efficient way to reduce the environmental impacts of pig production without compromising animal performance.

Machinery feeding development for sustainable aquaculture: Self-feeding system

Demand feeder is slightly different with an automatic feeder, it is altered to the appetite of fish because they can prefer which time they activate the feeder, also it triggered to produce a good growth performance and decrease the feed waste. Alternatively, some studies have been carried out for new method of automatic feeding system. Self-feeding system or previously familiar with the name of demand feeding system, is a system based on the learning ability of fish to activate the feeder and utilizing a feeding rhythm that may be controlled by the biological clock. At the past two decades, the development of self-feeding system is growing rapidly, from database, twenty eight studies with the most relevant data have been collected. The peak of paper published was in year 2000 with the most popular fish species was European sea bass (Dicentrarchus labrax, L.).

CONDIÇÃO CORPORAL DE FÊMEAS SUÍNAS NA GESTAÇÃO ALOJADAS EM BAIAS COLETIVAS COM DIFERENTES SISTEMAS DE ARRAÇOAMENTO

Landrace and Large White hybrid swine females were housed in collective pens during the gestation phase and submitted to different feeding systems. In one of the housing was used the manual feeding system, with feed provided directly on the floor. In the other, the electronic feeding system in a cage with free access Gestal 3G was installed. Two groups, composed of three matrices each, were separated by housing. The females were allocated according to their Body Condition Score (ECC) and birth order, seeking the homogeneity of the lots. The objective was to evaluate the variation of Body Weight (PC), ECC and Thickness of Bacon (ET) up to 107 days of gestation. For this purpose, CP and ECC measurements were performed every two weeks. ET was evaluated each 21 days. The data were submitted to descriptive and regression analysis over time. It was observed at the end of gestation that the group housed in the pens with an electronic feeding system showed less unevenness in relation to the PC and greater control of ECC. These results, added to the reduction of hierarchical disputes and for food competition, are important for maintaining the welfare of these females. Thus, automated feeding system proved to be important allies on the creation of pregnant swine matrices in collective pens.

76 Growth and Health of Limousin Crossbred Dairy-beef Calves in an Automated Feeding System

Abstract The objective of this study was to determine growth and health of Limousin crossbred dairy-beef calves fed alternative milk allowances in an automated group feeding system. The study was conducted at the University of Minnesota West Central Research and Outreach Center’s, Morris, MN dairy. Forty-eight Limousin-sired crossbred calves were assigned to feeding groups by birth order during two calving seasons from September to December 2019 and March to July 2020. Calves were introduced to the Holm & Laue HL100 Programmable Calf Feeder (Holm & Laue GmbH & Co KG, Westerronfeld, Germany) at 5 d and were randomly assigned to one of two treatments. Treatments for calves were 8 L/d (8L) or ad libitum (AL) milk allowance. Calves were weaned from the automated feeder at 56 d. Data were analyzed using PROC MIXED of SAS. Independent variables for analyses were the fixed effects of season of birth, sex of calf (M or F), treatment group and sex of calf nested within season of birth was a random effect. No differences (P > 0.05) were found between 8L or AL groups for birth weight. The AL calves (109.4 kg) had higher (P < 0.01) weaning weight than 8L calves (95.3 kg). Furthermore, the AL calves had higher (P < 0.01) hip height (95.6 cm) and greater (P < 0.01) heart girth (110.2) compared with 8L calves (93.8 cm and 104.8 cm, respectively). The AL calves (1.14 kg/d) had higher average daily gain at weaning compared to 8L calves (0.91 kg/d). Males calves were not different (P = 0.39) for average daily gain compared to female calves (1.07 kg/d versus 0.98 kg/d). Drinking speeds of AL calves were lesser (P < 0.05; 1,222 mL/min) than the 8L calves (1,453 mL/min). The AL calves and 8L calves were not different for hygiene scores or health scores. The results from this study indicate advantages to feeding dairy-beef calves ad libitum whole milk during the pre-weaning period.

Rancang Bangun Sistem Pemberian Pakan Ikan Secara Otomatis Berdasarkan Perilaku Ikan Menggunakan Kamera Berbasis Mini PC

This research was conducted because fish feeders are often forgotten by fish owners, so the researchers created an automatic fish feeding system using the Raspberry Pi, Camera Module-v2, Accelerometer Sensor, and Servo Motor. The way this tool works is the reading of water ripples carried out by the accelerometer sensor which later can get a trigger value to turn on the camera module-v2 and take pictures of the fish, the resulting image will be processed to identify the fish's mouth and calculate the number of fish mouths that appear to the surface. When the system can detect the number of fish mouths, the fish is hungry and the servo motor will open the food valve to release the fish food, but when the number of fish mouths is 0 or not detected, the servo motor will not open.

Automated feeding systems for shrimp: Effects of feeding schedules and passive feedback feeding systems

Shrimp aquaculture has been on a growing trend for the past four decades and its continued success will rely on efficient feeding protocols and reductions in labor cost. Various studies have demonstrated better growth and feed conversion for shrimp fed numerous meals in opposition to the traditional 1 to 4 meals offered during the day. With the adoption of automatic feeding systems by the shrimp industry not only can more feedings be delivered but also the time of day when feed is delivered is less problematic. This opens the door to looking at various feed management strategies. The goal of this work was to continue the development of a standard feeding protocol for timer feeders (SPTF) to maximize growth rates and production efficiency in semi-intensive pond production of shrimp through manipulation of feeding schedules. For this work, a 13-week pond production trial was performed in 16, 0.1 ha outdoors ponds, stocked at 35 shrimp/m2. Four treatments including: three fixed feeding treatments based on SPTF Day, SPTF Night and SPTF 115% 24 h were offered using automatic timer-feeders, and a fourth on demand treatment utilized AQ1 acoustic feeding system. To further evaluate different combinations of number of meals, feed quantities and time of feeding, a 11-week growth trial was conducted in 32, 800 L circular tanks in a recirculating green-water system. Results for the pond trial further confirm higher yields with AQ1 acoustic feeding system and showed no statistical differences among timer feeder treatments. Results in the tank trial indicated a relationship between growth response to increasing feed inputs and number of meals rather than feeding schedule alone. We also observed in the same trial a positive response on growth to more meals for identical feeding rates. Results confirm that increasing the number of feeding allows increased feed inputs and thus increased growth. The on demand feeding protocol using passive acoustics, resulted in the best performance of the shrimp.

Research on Automatic Bit Feeding Control System with Constant Weight on Bit Based on Fuzzy Predictive Control

According to the automatic bit feeding system of oil drilling rig has basic characteristics such as multi-variable, time-varying and nonlinear, an automatic bit feeding control system with constant weight on bit (WOB) based on fuzzy predictive control is proposed. The fuzzy predictive controller of WOB is designed, and the future output of the system is predicted by predictive control, and the output value of the system is close to the given value of WOB as much as possible by fuzzy control. The simulation results show that the response speed of the system is improved, which meets the requirements of small error and high precision, and has a certain guiding significance for the actual design and application.

Connecting farmer mental health with cow health and welfare on dairy farms using robotic milking systems

AbstractThe objective of this exploratory, preliminary study was to survey dairy farmers using robotic milking systems to better understand their mental health and potential connections to their cow health and welfare. Only farms using robotic milking systems in Ontario, Canada were visited for collection of data on management practices, cow welfare, and milk production and quality. Those farmers also completed an online survey that included validated psychometric scales used to assess resilience, stress, anxiety, and depression; results from 28 farms were analysed. Thirty cows per farm (or 30% for herds > 100 milking cows) were scored for body condition (five-point scale: 1 = thin to 5 = over-conditioned) and lameness (five-point scale: 1 = sound to 5 = lame); cows with a Body Condition Score ≤ 2.5 and lameness score ≥ 4 were defined as under-conditioned and severely lame, respectively. Farmer stress was positively associated with severe lameness prevalence, was greater for females vs males, and was greater for those feeding manually vs using an automated feeder. Anxiety and depression were greater for females vs males, and for those working alone, feeding manually, and with lesser milk protein percentage. Anxiety was also positively associated with the prevalence of severe lameness. Resilience was greater for those with automated feeding systems, but tended to be negatively associated with milk yield per robot and positively associated with milk somatic cell count. This is the first study to identify associations between farmer well-being and cow lameness, udder health, and milk yield. With future research, we can better understand this relationship to improve the well-being of both agricultural animals and their caretakers.

Multifunctional crust breaker for automatic alumina feeding system of aluminum reduction cell

For efficient operation of high-power aluminum reduction cells with prebaked anodes,full-time monitoring of the main technological parameters is required.This article discusses a multifunctional crust breaker of the automatic alumina feeding system. It provides the alumina supply to the bath by breaking the continuously solidifying crust on the surface of the melt. The multifunctional crust breaker is also a part of the automatic alumina feed system, providing regular automatic measurements of the process parameters.This article describes the development of a laboratory bench with a multifunctional crust breaking device. The goal and objectives are set. The design of the device is presented in the paper. The paper shows the advantages of using an automatic alumina feeding system with the developed multifunctional crust breaker.The positive effect of using the bench in the training process is discussed.

Genome-wide association study for residual concentrate intake using different approaches in Italian Brown Swiss

Residual feed intake (RFI) is the most used measure of feed efficiency. However, considering the importance of concentrates in the ration, a new index, the residual concentrate intake (RCI), was here defined. RCI aims to measure the individual efficiency in converting the concentrate into animal products. Brown Swiss young bulls (N = 736) were genotyped at 41,183 loci. Animals were housed in pens equipped with an automatic feeding system able to recognise the animal and record the concentrate intake. The diet consisted of concentrate and hay (ad libitum). The new RCI index was calculated as the residuals of the linear regression of concentrate intake on metabolic live weight and average daily gain. Animals were ranked according to their corrected RCI and divided into low (LRCI) and high phenotypes (HRCI). A low heritability (0.06 ± 0.03) was estimated using only genomics for this new index. Results from multivariate (M-GWAS) and Bayesian (B-GWAS) approaches were combined to identify SNP associated with RCI. The M-GWAS selected 698 SNPs potentially associated, whereas no significant markers were obtained in B-GWAS. Markers in the last approach were ranked according to their posterior inclusion probability and the first 698 were retained. Only SNPs in common between sorted B-GWAS and M-GWAS (N = 11) were considered associated with RCI. A total of 48 candidate genes were retrieved near these SNPs. Most of them were previously reported to be associated with feed efficiency and RFI. The combined use of multivariate and Bayesian techniques allow to identify SNPs associated with the investigated trait. Highlights RCI could be promising to select animals 48 candidate genes were found associated with RCI Multivariate technique allowed to identify significant SNPs

Feed conversion efficiency in sheep genetically selected for resistance to gastrointestinal nematodes

Context It has been indicated that there might be an antagonism between selection for gastrointestinal nematode resistance and high productivity and feed conversion efficiency in ruminants. Aims This study aimed to determine whether genetic selection for resistance to gastrointestinal nematodes would alter the feed intake and feed efficiency of sheep with or without an infection of Haemonchus contortus. Methods Sixty-seven Corriedale lambs (357 ± 14 days old) derived from flocks genetically selected to be resistant (n= 29) or susceptible (n = 38) to gastrointestinal nematodes (GIN) were evaluated for individual dry-matter intake (DMI), feed conversion ratio (FCR) and residual feed intake (RFI). Considering bodyweight (BW), GIN line and sires, males were allotted to one of three outdoor pens and females to one of two, each pen being equipped with five automated feeding systems and two automatic weighing platforms to record individual feed intake and BW. Feed (lucerne haylage, crude protein 20.5%, metabolisable energy 9.2 MJ/kg DM) and water were offered ad libitum. The experiment was conducted in two periods. First, animals were maintained worm-free (14 days of acclimatisation and 44 days of records) and then, in Period 2 (42 days), animals were artificially infected with 6000 L3 of Haemonchus contortus. Worm egg counts were recorded on Days 9, 23, 27, 30, 42 post-infection. While DMI, FCR, average daily gain and BW were analysed using a generalised linear model including dams age, pen and GIN line as fixed effects, RFI was analysed including only GIN line. Key results In both periods, GIN line did not have a significant (P > 0.05) effect on DMI, FCR, RFI, average daily gain or BW. Worm egg count was different (P < 0.05) on Day 23 post-infection (Period 2), being higher in susceptible line. Conclusions The most important finding of this study is that breeding GIN-resistant animals would not have a negative effect on feed conversion efficiency when evaluated as FCR or RFI in 1-year old lambs fed ad libitum with a high-protein diet. Implications Breeding for resistance to internal nematodes does not affect feed efficiency or productivity.

КОНЦЕПЦИЯ СОЗДАНИЯ ЦИФРОВОЙ СИСТЕМЫ УПРАВЛЕНИЯ ПРОЦЕССОМ НОРМИРОВАННОЙ ВЫДАЧИ КОНЦЕНТРИРОВАННЫХ КОРМОВ ЖИВОТНЫМ

Currently used systems for normalized distribution of concentrated feed to animals based on volumetric dispensers have a number of disadvantages that reduce their functionality and efficiency of practical use. (Research purpose) The research purpose is in developing the concept and main components of a digital control system for the process of normalized distribution of concentrated animal feed with automatic weight portion dosing of individual doses. (Materials and methods) The article proposes the concept of a system for managing the process of normalized distribution of concentrated animal feed, which consists in automatic calculation of individual feed doses taking into account the weight of animals, monitoring productivity, lactation periods, milk and feed quality, and generating digital data corresponding to the calculated doses. (Results and discussion) The article presents the concept of building a digital system for managing the processes of normalized distribution of concentrated animal feed. The article presents its structure and technological scheme. Author developed functional and schematic diagrams of the basic components: a code converter to an analog pneumatic signal, a system for addressing pneumatic signals, a device for comparing moments of forces; algorithms for the functioning of the system and its unified basic components. (Conclusions) The automatic concentrate feeding system allows for more accurate and balanced feeding of each animal. The portion, weight normalized distribution of concentrated feed to animals according to the schedules established by the zootechnical services of enterprises contributes to the development of their genetic potential and the preservation of animal health. The power supply and control signals of individual mechatronic, weight, and portion dispensers have a single physical nature and level, which simplifies and increases the reliability of the “Ration” system.

The effects of manual and automated milk feeding methods on group-housed calf health, behaviour, growth and labour

It has been suggested that the integration of automatic feeding systems into calf rearing programmes has the potential to improve calf behaviour, growth and the associated labour. Thus, the objective of this study was to compare the effects of automatic and manual feeding systems on calf health, behaviour, growth and labour. A population of 60 dairy heifer calves was used: 44 Holstein-Friesian (HF) and 16 HF x Jersey (JE), balanced for birth weight (33 ± 4.1 kg), birth date (26 January ± 3.2 days) and breed. The experiment was a randomised block design including two treatments; i) automated calf feeding system (AFS) and ii) manual calf feeding system (MFS). Each treatment was replicated once, so a total of four balanced groups of 15 heifer calves were created. Milk replacer was offered at a rate of 6 L per calf/day (reconstitution rate 15%), with fresh water, ad-libitum concentrates and hay offered from three days old. Calves were weaned based on weight (90 kg for HF and 85 kg for HF x JE). Total labour input/day was consistently less for AFS compared to MFS (-00:01:06 per calf/day). Automatic feeding systems had a higher labour requirement for health inspections and training to the system (+00:00:15 per calf/day and +00:02:06 per calf/day, respectively), on a per calf basis, compared to MFS. The MFS-calves had an increased likelihood of experiencing faecal scores > 0 (Odds Ratio (OR) = 2.009; Confidence Interval (CI) = 1.463 – 2.759). The MFS-calves were also more likely to defecate and urinate (OR= 1.450; CI = 1.080-1.945), eat (OR= 1.281; CI = 1.140 – 1.439) and socially interact (OR= 1.300; CI = 1.111 – 1.521), compared to standing. There was no difference in number of days from birth to weaning (80.8 days) and weight at weaning (92.9 kg); average daily gain in both the pre (81 days) and post weaning (79 days) periods was similar between the two treatments (0.74 and 0.70 kg/day, respectively). Patterns for behaviours such as lying and playing were similar and low levels of abnormal behaviours were found in both treatments. Calves in both treatments exhibited good health and normal behavioural patterns as well as similar growth rates. Thus, when managed appropriately, the saving of labour is a distinct advantage automated feeding systems have over their manual counterparts when rearing group-housed calves.

Radiated temperature from thermal imaging is related to feed consumption, growth rate and feed efficiency in grower pigs.

Individual feed consumption and animal weight were continuously recorded in grower pigs using an automated feeding system. Infrared images were recorded each time a pig entered the feeding system and infrared thermography provided radiated thermal measurements of the dorsal surface of each animal. Feed was withdrawn and the animals fasted for a period of 24h three times during the growth of the animals at body weights of approximately 35, 65 and 105kg. There was a significant reduction of 0.28°C in the maximum surface temperature (Tmax), and 0.48°C in the average surface temperature (Tmean) during the periods of fasting. Maximum and average pig temperatures exhibited negative correlations to feed consumption and growth variables. There were negative correlations of residual feed intake (RFI) to Tmax and Tmean radiated temperatures. There were positive correlations of residual gain (RG) and residual intake and gain (RIG) with Tmax and Tmean. The Tmax and Tmean temperature responses to fasting were negatively associated with feed consumption and growth variables. Absolute temperature and temperature response variables were positively associated with RFI and negatively associated with residual intake and gain (RIG). These findings provide support for the concept of radiated heat losses as a measure of metabolic activity and a predictor of growth performance.

Automated feeding of sheep. 1. Changes in feeding behaviour in response to restricted and ad libitum feeding

Context Automated feeding units allow the recording of individual feeding behaviour of group-housed sheep and provide data for research into feed efficiency. Aim It was hypothesised that measures of feeding behaviour such as the number of non-feeding events, meal size, eating rate and meal duration would change under different levels of feeding. Method Maternal Composite ewes (n = 126, 18 per pen) were fed a hay-based pellet using automated feeding units (2 per pen) for four periods differing in total daily feed allowance (kg/day) and meal allowance (g/meal). Sheep were initially fed ad libitum (meal allowance ~1000 g) for 19 days during an adaptation period, before restricted feeding for 41 days at daily allowances of 40%, 60%, 80%, 100%, 140% and 180% of estimated maintenance requirements, with a meal allowance of ~100 g. These restricted daily allowances were the experimental treatments that were randomly applied to sheep and replicated three times per pen. The daily allowance was then adjusted to 1.4 kg/day (with a ~200 g meal allowance) for all sheep over 5 days, before ad libitum feeding of all sheep for a period of 16 days. All feeding and non-feeding events were recorded. Key results Under restricted feeding, sheep altered the timing of their meals to consume more meals during the early morning after daily allowances were reset at 0000 hours. This change was more pronounced for sheep fed a smaller proportion of maintenance. The number of non-feeding events (~8/day) was not affected by the level of restricted feeding, but meal size was smaller, meal duration was longer and eating rate was lower for sheep fed 40% of their maintenance requirement. Under ad libitum feeding, sheep reverted to a preferred meal size and number of meals, with fewer than two non-feeding events per day, but differences in eating rate remained. Conclusions Sheep feeding behaviours adapt and respond quickly to changes in daily allowance and offered meal size, but the similar number of non-feeding events at different proportions of maintenance feeding suggest that non-feeding events may not reflect levels of hunger. Implications Our observations suggest that sheep are capable of learning and adapting to different levels of feeding and that this may allow for automated feeding systems to supplementary feed larger numbers of sheep under extensive situations.

Monitoring alumina content in cryolite-alumina melt

Alumina content in electrolysis cells for aluminum production is one of the most important and poorly controlled parameters. The alumina is delivered to the cell by means of an alumina automatic feeding system, adjusted to the amperage or to the voltage alteration. However, a change in the alumina content in the cryolite-alumina melt depends not only on the current; and the voltage is not a parameter that responds only to the alumina amount in the melt. In order to check the current value of alumina content as well as the dissolution of alumina in industrial electrolytes (NaF-AlF3-CaF2-Al2O3), a novel electrochemical sensor was proposed. It was comprised of a carbon working electrode and a counter electrode interacting with aluminum. The sensor was easy to manufacture, and it allowed reducing the measurement error associated with back reactions at the working electrode. The novel approach was considered on an ex-ample of dissolving the alumina in the NaF-AlF3-(5 wt%)CaF2 melt ([NaF]/[AlF3] = 2.1 mol/mol) containing alumina (Al2O3) in amount of 0.69-4.51 wt% at 970 °C in conditions of natural and forced convection. It was found that the alumina solubility in the studied melt was 4.51 wt%. Depending on the initial content of alumina in the melt and convection conditions, its dissolution rate varied up to 0.36 mol/s·m3.