Loose farrowing pens have been considered as alternatives to crates to enhance sow welfare. A major concern with pen systems is often higher piglet pre-weaning mortality, especially due to crushing by the sow. An optimal management of light and mat surface temperature may promote greater piglet use of the creep, which has been associated with reduced piglet crushing. A total of 108 sows and their piglets were studied in sow welfare and piglet protection pens on a commercial piggery, across two replicates. Sows were randomly assigned to pens arranged within two creep treatments (bright creep: 300 lx v. dark creep: 4 lx), considering mat temperature as a covariate. Twelve sows and their litters in each treatment (24 in total) had their behaviour continuously recorded for 72-h postpartum (pp), and four focal piglets per litter were weighed on the first and third days pp. In situ behaviour observations were performed daily (from 0800 to 1700 h) on all sows and their litters, every 15 min over 72-h pp to record piglet time spent in the creep, latency to enter the creep for the first time, latency for the litter to remain in the creep for at least 10 min, and piglet and sow use of pen areas immediately in front of (A2) and farthest from the creep (A3). Piglets with access to bright creeps spent on average 7.2% more time (P<0.01) in the creeps than piglets in pens with Dark creeps. In addition, for each degree increase in mat temperature, piglets spent on average 2.1% more time (P<0.01) in the creep. Piglets in pens with bright creeps spent less time in A2 (P=0.04) and the least time in A3 (P=0.01). Light or mat temperature did not affect sow use of pen areas or piglet weight gain. Piglets with bright creeps tended (P=0.06) to take longer to enter the creep for the first time after birth, but the latency for 30.0% of the litter to remain clustered for 10 min tended (P=0.08) to be shorter in bright compared to dark creeps. Overall, piglet use of the creep increased with warm mat temperatures and brightness, which should be further investigated as potential strategies to promote piglet safety and reduce crushing in pen farrowing systems.

Laying hens housed in free-range systems have access to an outdoor range, and individual hens within a flock differ in their ranging behaviour. Whether there is a link between ranging and laying hen welfare remains unclear. We analysed the relationships between ranging by individual hens on a commercial free-range layer farm and behavioural, physiological and health measures of animal welfare. We hypothesised that hens that access the range more will be (1) less fearful in general and in response to novelty and humans, (2) have better health in terms of physical body condition and (3) have a reduced physiological stress response to behavioural tests of fear and health assessments than hens that use the range less. Using radio frequency identification tracking across two flocks, we recorded individual hens’ frequency, duration and consistency of ranging. We also assessed how far hens ventured into the range based on three zones: 0 to 2.4, 2.4 to 11.4 or >11.4 m from the shed. We assessed hen welfare using a variety of measures including: tonic immobility, open field, novel object, human approach, and human avoidance (HAV) behavioural tests; stress-induced plasma corticosterone response and faecal glucocorticoid metabolites; live weight, comb colour, and beak, plumage, footpad, and keel bone condition. Range use was positively correlated with plasma corticosterone response, faecal glucocorticoid metabolites, and greater flight distance during HAV. Hens that used the range more, moved towards rather than away from the novel object more often than hens that ranged less. Distance ranged from the shed was significantly associated with comb colour and beak condition, in that hens with darker combs and more intact beaks ranged further. Overall the findings suggest that there is no strong link between outdoor range usage and laying hen welfare. Alternatively, it may be that hens that differed in their ranging behaviour showed few differences in measures of welfare because free-range systems provide hens with adequate choice to cope with their environment. Further research into the relationship between individual range access and welfare is needed to test this possibility.

Temporary confinement during parturition and early postpartum may provide an intermediary step preceding loose housing that offers improvement in sow and piglet welfare. Three experiments were conducted to investigate the implications of replacing farrowing crates (FCs) with an alternative housing system from 3 days postpartum until weaning. In each experiment sows farrowed in FCs and were randomly allocated at day 3 of lactation to either a FC or a pen with increased floor space (lactation pen (LP)) until weaning. In experiment 1, piglet growth and sow and piglet skin injuries were recorded for 32 sows and 128 focal piglets in these litters. Behaviour around nursing and piglet behavioural time budgets were also recorded for 24 of these litters (96 focal piglets for time budgets). In experiment 2, measures of skin injury and behavioural time budgets were conducted on 28 sows and 112 focal piglets. The behavioural response of sows to piglet vocalisation (maternal responsiveness test (MRT)) was also assessed. In experiment 3, piglet mortality from day 3 of lactation until weaning was recorded in 672 litters over 12 months. While housing did not affect piglet weight gain in experiment 1, or piglet skin injuries in experiments 1 or 2, sows in both experiments sustained more injuries in LP than FC (experiment 1, 2.9 v. 1.4; experiment 2, 2.5 v. 0.8 lesions/sow; P<0.05). Sow–piglet interactions were more frequent in LP than FC at days 11 and 18 postpartum in both experiment 1 (day 11, 1.4% v. 1.2%; day 18, 1.7% v. 1.0% of observations; P=0.05) and 2 (day 11, 1.0% v. 0.3%; and at day 18 were 1.0% v. 0.6% of observations; P<0.01), and LP sows were more responsive in the MRT in experiment 2 (2 v. 0 median number of tests in which sows react, P<0.01). In experiment 1 piglets played more (0.7% v. 0.3% of observations, P=0.05) and manipulated others less (0.3% v. 0.7% of observations, P=0.04) in LP, but more piglets missed nursing bouts (0.2 v. 0.1 piglets/bout, P<0.01) compared with FC. There was no effect of housing on piglet mortality from day 3 of lactation until weaning in experiment 3 (0.63 and 0.64 deaths/litter for LP and FC, respectively, P>0.05). Thus, housing sows and litters in LP from day 3 of lactation minimises piglet mortality while improving maternal behaviour in sows and social behaviour in piglets.

Severe feather-pecking (SFP) persists as a highly prevalent and detrimental behavioural problem in laying hens (Gallus gallus domesticus) worldwide. The present experiment investigated the association between feather-eating and plumage damage, a consequence of SFP, in groups of free-range, ISA Brown laying hens. Single feathers were placed on the floor of the home pens. Feathers were sourced from seven different birds. A total of 50 birds in six pens with extensive plumage damage were compared with birds in six control pens with little plumage damage at 41 to 43 weeks of age (n=12 pens, 600 hens). Birds in pens with extensive plumage damage ingested more feathers (F=8.1, DF=1, 8, P=0.02), and also showed shorter latencies to peck at (χ2=54.5, DF=1, P<0.001), and ingest feathers (χ2=55.6, DF=1, P<0.001). Birds ingested feathers from a bird in the free-range facility, in which the testing took place, more quickly than from a bird housed in a separate cage facility (χ2 = 39.0, DF=6, P<0.001). A second experiment investigated the predictive relationship between feather-eating and plumage damage. Feathers were presented to 16 pens of 50 pullets prior to the development of plumage damage, at 15 weeks of age, and then to the same hens after plumage damage had become prominent, at 40 weeks of age. Birds had a higher probability of ingesting feathers (F=142.0, DF=1, 231, P<0.001), pecked feathers more times (F=11.24, DF=1, 239, P<0.001), and also pecked (χ2 = 127.3, DF=1, P<0.001) and ingested (χ2=189.3, DF=1, P<0.001) the feathers more quickly at 40 than 15 weeks of age. There was a trend for an interaction, where birds pecked feathers from the rump more times than feathers from the back at 40 weeks of age (F=3.46, DF=1, 237, P=0.06). However, a lack of variability in plumage damage between pens in this experiment precluded investigation of the predictive relationship. The results from the present study confirm the association between feather-eating and plumage damage, and suggest that birds may prefer feathers from particular body areas and from particular hens. Future experiments should focus on elucidating whether feather-eating may act as a predictor of SFP.

Severe feather-pecking (SFP), a particularly injurious behaviour in laying hens (Gallus gallus domesticus), is thought to be negatively correlated with range use in free-range systems. In turn, range use is thought to be inversely associated with fearfulness, where fearful birds may be less likely to venture outside. However, very few experiments have investigated the proposed association between range use and fearfulness. This experiment investigated associations between range use (time spent outside), fearfulness, plumage damage, and BW. Two pens of 50 ISA Brown laying hens (n=100) were fitted with radio frequency identification (RFID) transponders (contained within silicone leg rings) at 26 weeks of age. Data were then collected over 13 days. A total of 95% of birds accessed the outdoor run more than once per day. Birds spent an average duration of 6.1 h outside each day over 11 visits per bird per day (51.5 min per visit). The top 15 and bottom 15 range users (n=30), as determined by the total time spent on the range over 13 days, were selected for study. These birds were tonic immobility (TI) tested at the end of the trial and were feather-scored and weighed after TI testing. Birds with longer TI durations spent less time outside (P=0.01). Plumage damage was not associated with range use (P=0.68). The small group sizes used in this experiment may have been conducive to the high numbers of birds utilising the outdoor range area. The RFID technology collected a large amount of data on range access in the tagged birds, and provides a potential means for quantitatively assessing range access in laying hens. The present findings indicate a negative association between fearfulness and range use. However, the proposed negative association between plumage damage and range use was not supported. The relationships between range use, fearfulness, and SFP warrant further research.

The Australian dairy herd size has doubled over the last 20 years substantially increasing the time that farmers require for individual animal attention to monitor and intervene with events such as calving. Technology will help focus this limited labour resource on individual cows that require assistance. The objective of this experiment was to first determine the profiles of rumination duration and level of activity as determined by sensors between, and within, days around calving and second to use these data to predict the day of calving for pasture-based dairy cows. After 2 weeks from the expected calving date, 27 cows were fitted with SCR HR LD Tags, located in 40×90 m2 paddock and offered ad libitum oaten hay and 2 kg grain-based concentrate/cow per day until calving. Hourly activity and rumination data for each cow, as determined by the SCR tags, were fitted with linear mixed models and all parameters were estimated using restricted maximum likelihood. Rumination duration decreased by 33% over the day prior and the day of calving, with the decline in rumination duration starting the day prepartum. Activity levels were maintained prepartum but increased in the days postpartum. The day of calving was recorded and used to determine the gold standard positive (the day before calving) and negative (all other) dates. A threshold rumination level of 0.9 (decline in rumination duration of 10%) gave the optimal combination of 70% sensitivity and 70% specificity. This experiment shows the potential to use rumination duration to predict the day of calving and the opportunity to use sensor data to monitor animal health.

The interaction between calcium (Ca) and non-phytate phosphorus (nPP) in broiler nutrition and skeletal health is highly complex with many factors influencing their digestion, absorption and utilisation. The use of an investigative model such as the geometric framework allows a graphical approach to explore these complex interactions. A total of 600 Ross 308-day-old male broiler chicks were allocated to one of 15 dietary treatments with five replicates and eight birds per replicate. Dietary treatments were formulated to one of three total densities of total Ca+nPP; high (15 g/kg), medium (13.5 g/kg) and low (12 g/kg) and at each density there were five different ratios of Ca : nPP (4, 2.75, 2.1, 1.5 and 1.14 : 1). Weekly performance data was collected and at the end of the experiment birds were individually weighed and the right leg removed for tibia ash analysis. Skeletal health was assessed using the latency to lie (LTL) at day 27. At low Ca and high nPP as well as high Ca and low nPP diets, birds had reduced feed intake, BW gain, poorer feed efficiency and lower tibia ash, resulting in a significant interaction between dietary Ca and nPP (P<0.05). LTL times were negatively influenced by diets having either a broad ratio (high Ca, low nPP) or too narrow a ratio (low Ca, high nPP) indicating that shorter LTL times may be influenced by the ratio of Ca : nPP rather than absolute concentrations of either mineral. The calculated intake arrays show that broilers more closely regulate Ca intake than nPP intake. Broilers are willing to over consume nPP to defend a Ca intake target more so than they are willing to over consume Ca to defend an nPP target. Overall dietary nPP was more influential on performance metrics, however, from the data it may appear that birds prioritise Ca intake over nPP and broadly ate to meet this requirement. As broilers are more willing to eat to a Ca intake target rather than an nPP intake target, this emphasises the importance of formulating diets to a accurately balanced density of Ca : nPP considering the biological importance of both minerals.

In bulk form, Si1-xGex is a promising thermoelectric material for high temperature applications. In this paper, we report results from an experimental study as well as theoretical modeling of the quantum confinement effect on the enhancement of the thermoelectric figure of merit. Si/Si1-xGex, multiple quantum well structures are fabricated using molecular beam epitaxy (MBE) on SOI (Silicon-on-Insulator) substrates in order to eliminate substrate effects, especially on the Seebeck coefficient. A method to eliminate the influence of the buffer layer on the thermoelectric characterization is presented. An enhancement of the thermoelectric figure of merit within the quantum well over the bulk value is observed.

Enhanced ZT has been predicted theoretically and observed experimentally in 2D quantum wells, with good agreement between theory and experiment. Advantages of low dimensional systems for thermoelectric applications are described and prospects for further enhancement of ZT are discussed.

Sputtered A1N films developed for piezoelectric resonators are extremely chemically reactive. As-sputtered films react with boiling water resulting in a complete loss of the AIN bond structure. Experiments to determine the effect on chemical stability of annealing the sputtered films at 1000 °C, indicate annealing in an oxidizing gas leads to partial oxidation of AlN. Annealing in an inert gas prevents oxidation but does not protect the films from attack by boiling water. Annealing in a reducing gas followed by annealing in an inert gas renders A1N films stable in boiling water. A1N film structure and composition have been studied via Refractive Index, XRD, SIMS, SEM, AES, XPS and FTIR evaluations.

Auditory evoked potentials were recorded in a choice reaction-time task. This test paradigm elicited the attention-related P300 component and was used to study cognitive processing. Compared with age-matched controls, 17 patients with dementia of the Alzheimer type were shown to have significantly longer reaction times as well as delayed latencies of several components of the auditory evoked potentials. The fractional increase in the reaction times was much greater than that of the P300 peak latency. The latter is commonly accepted as an index of stimulus-evaluation time. These findings suggest a delay in both response selection and stimulus evaluation.

In response to tethering, many sows develop seemingly non-functional repetitive behaviour (stereotypies), which may be performed for several hours in a day.

The quality and quantity of activity performed by sows with different degrees of adaptation to tethering was studied in relation to energy expenditure. Three groups of five sows were recognized: (1) High, sows which showed a high incidence of stereotyped activity after prolonged tethering; (2) T/Low, sows with limited experience of tethers; and (3) G/Low, the same sows as in group 2 after regrouping.

High sows were about three times more active than T/Low sows: the proportions of time involved in 24 h were 0·35 and 0·13 respectively. Most of the former sows' activity was in the form of sterotypies. The activity level of the G/Low sows was between that of the two tether treatments (proportionately 0·17 of 24 h). Both tethered treatments spent proportionately about 0·05 of 24 h in using drinkers compared with proportionately less than 0·02 of the time for the G/Low sows.

High sows produced proportionately 0·36 more heat than T/Low sows during the 12-h light period in each day. During this period, proportionately 0·40 and 0·20 of heat production from High and T/Low sows was associated with activity. The diurnal activity of the G/Low sows was associated with proportionately 0·24 of heat production.

Stereotypies and excessive drinker use accounted for proportionately 0·86, 0·52 and 0·24 of the activity of High, T/Low and G/Low sows. The proportions of metabolizable energy intake required for these activities were 0·23, 0·07 and 0·04 respectively for the three treatments. The study concludes that tethering is stressful when sows develop, and then indulge in frequent coping behavioural patterns which increase metabolic rate.