Not all dogs are equal: perception of canine welfare varies with context

Community attitudes drive societal expectations, influencing government and industry regulations that determine standards of care for industries reliant on animals. It is important for dog industry stakeholders to understand public perceptions and attitudes, to inform management strategy priorities relating to animal welfare. This study sought to determine if the welfare status of dogs (Canis familiaris) is important to people and whether the perceived level of welfare varies with dog context (eg companion, protection, stock herding, assistance, sporting, free-roaming, wild, etc). Over 2,000 self-selected adults completed a voluntary, internet-based questionnaire. Responses were received from more than twelve countries and from a range of stakeholders with varied experiences. Perceived welfare status of dogs varied significantly across 17 dog contexts and roles, from extremely low (eg fighting dogs) to very high (eg guide dogs). Over 95% of respondents agreed that the welfare of dogs was very important to them. Demographic features of respondents did not relate to meaningful differences in reported importance of canine welfare or ratings of perceived welfare of dogs. The constructs underlying how people perceive the welfare of dogs appear complex and multi-dimensional. As public scrutiny forces reassessment of the welfare status of animals used in various contexts, proactive management of perceived welfare issues by companion and working dog industry stakeholders, including government, industry organisations, advocacy groups, and animal welfare researchers, is likely to be key to the sustainable participation of dogs in these roles.

Structural Insights Into PfARO and Characterization of its Interaction With PfAIP

Apicomplexan parasites contain rhoptries, which are specialized secretory organelles that coordinate host cell invasion. During the process of invasion, rhoptries secrete their contents to facilitate interaction with, and entry into, the host cell. Here, we report the crystal structure of the rhoptry protein Armadillo Repeats-Only (ARO) from the human malaria parasite, Plasmodium falciparum (PfARO). The structure of PfARO comprises five tandem Armadillo-like (ARM) repeats, with adjacent ARM repeats stacked in a head-to-tail orientation resulting in PfARO adopting an elongated curved shape. Interestingly, the concave face of PfARO contains two distinct patches of highly conserved residues that appear to play an important role in protein-protein interaction. We functionally characterized the P. falciparum homolog of ARO interacting protein (PfAIP) and demonstrate that it localizes to the rhoptries. We show that conditional mislocalization of PfAIP leads to deficient red blood cell invasion. Guided by the structure, we identified mutations of PfARO that lead to mislocalization of PfAIP. Using proximity-based biotinylation we probe into PfAIP interacting proteins.

Dissecting the Gene Expression, Localization, Membrane Topology, and Function of the Plasmodium falciparum STEVOR Protein Family

During its intraerythrocytic development, the malaria parasite Plasmodium falciparum exposes variant surface antigens (VSAs) on infected erythrocytes to establish and maintain an infection. One family of small VSAs is the polymorphic STEVOR proteins, which are marked for export to the host cell surface through their PEXEL signal peptide. Interestingly, some STEVORs have also been reported to localize to the parasite plasma membrane and apical organelles, pointing toward a putative function in host cell egress or invasion. Using deep RNA sequencing analysis, we characterized P. falciparumstevor gene expression across the intraerythrocytic development cycle, including free merozoites, in detail and used the resulting stevor expression profiles for hierarchical clustering. We found that most stevor genes show biphasic expression oscillation, with maximum expression during trophozoite stages and a second peak in late schizonts. We selected four STEVOR variants, confirmed the expected export of these proteins to the host cell membrane, and tracked them to a secondary location, either to the parasite plasma membrane or the secretory organelles of merozoites in late schizont stages. We investigated the function of a particular STEVOR that showed rhoptry localization and demonstrated its role at the parasite-host interface during host cell invasion by specific antisera and targeted gene disruption. Experimentally determined membrane topology of this STEVOR revealed a single transmembrane domain exposing the semiconserved as well as variable protein regions to the cell surface.IMPORTANCE Malaria claims about half a million lives each year. Plasmodium falciparum, the causative agent of the most severe form of the disease, uses proteins that are translocated to the surface of infected erythrocytes for immune evasion. To circumvent the detection of these gene products by the immune system, the parasite evolved a complex strategy that includes gene duplications and elaborate sequence polymorphism. STEVORs are one family of these variant surface antigens and are encoded by about 40 genes. Using deep RNA sequencing of blood-stage parasites, including free merozoites, we first established stevor expression of the cultured isolate and compared it with published transcriptomes. We reveal a biphasic expression of most stevor genes and confirm this for individual STEVORs at the protein level. The membrane topology of a rhoptry-associated variant was experimentally elucidated and linked to host cell invasion, underlining the importance of this multifunctional protein family for parasite proliferation.

Erratum to: Oxytocin enhances the appropriate use of human social cues by the domestic dog (Canis familiaris) in an object choice task

Erratum to: Anim Cogn (2015) 18:767–775 DOI 10.1007/s10071-015-0843-7. Unfortunately, in the original publication the word ‘receptor’ under the sub-heading ‘The effect of gender on the efficacy of oxytocin’ has been incorrectly published as ‘peptide’. The correct text should read as below. Oestrogen is known to enhance the production of oxytocin and its receptor (Rissman 2008), and this may explain why the female dogs in this study did not perform as well as human female subjects in other tests of social cognition, as the majority (88 %) had been spayed, thereby reducing the volume of oestrogen their bodies would be producing. The online version of the original article can be found under doi:10.1007/s10071-015-0843-7.

Oxytocin enhances the appropriate use of human social cues by the domestic dog (Canis familiaris) in an object choice task

It has been postulated that the neuropeptide, oxytocin, is involved in human-dog bonding. This may explain why dogs, compared to wolves, are such good performers on object choice tasks, which test their ability to attend to, and use, human social cues in order to find hidden food treats. The objective of this study was to investigate the effect of intranasal oxytocin administration, which is known to increase social cognition in humans, on domestic dogs' ability to perform such a task. We hypothesised that dogs would perform better on the task after an intranasal treatment of oxytocin. Sixty-two (31 males and 31 females) pet dogs completed the experiment over two different testing sessions, 5-15 days apart. Intranasal oxytocin or a saline control was administered 45 min before each session. All dogs received both treatments in a pseudo-randomised, counterbalanced order. Data were collected as scores out of ten for each of the four blocks of trials in each session. Two blocks of trials were conducted using a momentary distal pointing cue and two using a gazing cue, given by the experimenter. Oxytocin enhanced performance using momentary distal pointing cues, and this enhanced level of performance was maintained over 5-15 days time in the absence of oxytocin. Oxytocin also decreased aversion to gazing cues, in that performance was below chance levels after saline administration but at chance levels after oxytocin administration.

morphometric variation associated with teat-number differences in Antechinus agilis and A. swainsonii ? Observations from the Otway Ranges, Victoria

That there is intraspecific variation in teat-number in Antechinus agilis (agile antechinus) and A. swainsonii (dusky antechinus) has been known for a long time. Our aim was to determine whether other key morphometric traits differed among individuals with different numbers of teats. External body dimensions and pelage characteristics were measured on live individuals and compared. Within-species variation in some external body dimensions (tail, pes, and snout-vent length) coincided with teat-number differentiation in both antechinus species in the Otway Ranges, Victoria. Disparities in pelage colour and markings were apparent between A. agilis 6- and 10-teat phenotypes, but were not obvious among A. swainsonii teat phenotypes. Although small sample sizes obviated statistical analysis, we tentatively concluded that female A. agilis with 7, 8, or 9 teats in the Otway Ranges probably displayed morphometric and pelage characteristics intermediate between those of 6- and 10-teat individuals. A comparison of morphometric traits among 6-teat A. agilis from different geographic areas (Otways, Portland and Wilsons Promontory) also revealed some variation. This result was consistent with an expectation of clinal variation in external morphology among antechinus. Overall, this study indicates that localized disparities that are associated with teat-number, as well as clinal differences occurring over large geographic distances, contribute to intraspecific variation in external morphology in antechinus.

Phylogeography and environmental correlates of a cap on reproduction: teat number in a small marsupial, Antechinus agilis

Natural selection should optimize litter size in response to the distribution and abundance of resources during breeding. In semelparous, litter-bearing antechinuses, teat number limits litter size. Consequently adaptation has been inferred in explaining intraspecific, geographic variability in teat number for several Antechinus spp. The phylogeography of teat number variation and associated genetic divergence were assessed in A. agilis using nine microsatellites and mitochondrial cytochrome b sequence data. Six-teat Otway Range animals were divergent in microsatellite allele identity and frequencies: samples from three Otway six-teat sites demonstrated significantly greater similarity genetically to those from six-teat animals approximately 250 km to the west, than to nearby Otway 10-teat samples, or to the six-teat animals at Wilsons Promontory. Gene flow between Otway phenotypes appears to have been limited for sufficient time to enable different microsatellite alleles to evolve. Nonetheless, nuclear genetic evidence suggested only incomplete reproductive isolation, and mitochondrial DNA (mtDNA) haplotypes showed no association with teat number. Other populations across the range were no more genetically differentiated from one another than expected from geographic separation. Principal components and distance-based redundancy analyses found an association between environmental variables and geographic distribution of A. agilis teat number - six-teat animals inhabit more temperate forests, whilst those with more teats experience greater seasonality. The apparent restricted breeding between phenotypically distinct animals, together with phylogenetically separate groups of six-teat animals in different locations with similar environments, are consistent with the hypothesis that adaptation to different habitats drives teat number variation in A. agilis.

The response of captive silvereyes (Zosterops lateralis) to the colour and size of fruit

Birds are important consumers and dispersers of the seeds of fleshy fruit and some have been shown to be selective in their choice of fruit. However, our knowledge of how birds respond to a variety of fruit characteristics is poor. Some birds are known to avoid green fruit or consume them less than fruit of other colours. The fruit of many plant species are green when they are unripe and contain low concentrations of sugars and high concentrations of secondary compounds. In this study, captive silvereyes (Zosterops lateralis) were presented with a choice of red, white and green artificial fruit. Half of them were given these fruit with equal sugar concentrations (15%) and the other half were given the choice but with the green fruit having a sugar concentration twice that of the other two colours (30%). Green fruit were not strongly avoided by silvereyes and were actually preferred when they had a higher sugar concentration than the other two fruit types (red and white). Sugar concentration was therefore a more important determinant of fruit choice than colour. Fruit size is also known to affect fruit choice in some bird species. Small fruit are easier to consume than larger fruit, but contain less pulp. To maximise energy gain, birds should consume fruit that are large, but not large enough to incur high handling costs. Silvereyes in this study were presented with a choice between 20 artificial fruit 4 mm in diameter (large fruit) and 20 artificial fruit 2 mm in diameter (small fruit), both of which they are able to consume. In this experiment, silvereyes exhibited a strong preference for large fruit over small fruit. In general, larger fruit contain more pulp and therefore more energy than smaller fruit. However, other fruit traits, such as seed load, are likely to influence fruit choice by silvereyes in the wild and result in a trait hierarchy.

Seasonal variation in body mass and blood oxygen carrying capacity of the superb fairy-wren (Malurus cyaneus)

The responses of small birds to many seasonal energy challenges include enhancement of aspects of aerobic metabolism, sometimes involving an increase in the rate of oxygen delivery to the metabolising tissues. One such mechanism that enhances oxygen delivery seasonally is an increase in blood oxygen carrying capacity. This response is enhanced in birds because of their rapid erythrocyte turnover rate. Some small birds have also evolved winter fattening, which helps them to meet the energy challenge presented by winter conditions. Such adaptations, while well documented for North Temperate birds, have received little attention in birds inhabiting temperate Australia. Over a two-year period, we examined seasonal changes in mass, an approximate indicator of fattening, and the parameters determining blood oxygen carrying capacity in a population of superb fairy-wrens (Malurus cyaneus) in outer Melbourne, Australia. Body mass did not vary significantly seasonally, but haematocrit and whole blood haemoglobin were significantly higher in the breeding season than at other times of year and the erythrocyte count was significantly higher in spring than in autumn. We conclude that the failure of the fairy-wrens to increase mass in winter (i.e. show marked winter fattening) was probably due to the comparative mildness of the climate and to the known fitness costs of fat storage. The significant 18% increase in blood oxygen carrying capacity in spring probably helped the birds to meet the additional energy requirements of breeding, particularly the likely increase in flight activity. However, given the magnitude of the increase, other mechanisms must have been involved in meeting breeding costs. The seasonal peak in blood oxygen carrying capacity did not coincide with the time when moulting was most pronounced.

Use of Tree Hollows by Two Sympatric Gliding Possums, The Squirrel Glider, Petaurus norfolcensis and The Sugar Glider, P. breviceps

Populations of the Squirrel Glider, Petaurus norfolcensis and the Sugar Glider, P. breviceps, are often sympatric and the two species are potential competitors for tree hollows. Their use of hollows and artificial nest-boxes was examined in a Box-Ironbark forest where natural hollows are scarce due to past forestry practices. We found gliders used hollows in the boles and branches of trees and in coppicing stumps. There was considerable interspecific overlap in the use of hollows and nest-boxes, both by gliders and other birds and mammals. Both gliders preferred hollows and nest-boxes with narrow entrances (<50 mm diameter). Petaurus breviceps preferred nest-boxes and possibly natural tree hollows with entrances too narrow for the larger P. norfolcensis. When abundant nest-boxes of this type were introduced at the study site, P. breviceps numbers increased and then decreased when the nest-boxes were removed. The results suggest that the larger P. norfolcensis monopolise the best available hollows. Petaurus breviceps numbers may have been limited by a lack of suitable hollows.

Hematological and Body-Mass Changes of Small Passerines Overwintering in South-Eastern Australia

Haematological parameters and body mass of four passerine bird species resident in south-eastern Australia were compared in winter and summer to determine whether there were changes indicative of metabolic adjustments associated with seasonal acclimatisation. Haematocrit and whole-blood haemoglobin content did not change seasonally, but erythrocyte numbers increased (by 45-72%) and erythrocyte volume decreased (by 40-73%) significantly in winter in all species. The greater surface area to volume ratio and shorter diffusion pathway of smaller erythrocytes in winter should enhance blood oxygen transport efficiency and thus potentially facilitate metabolic acclimatisation to cold stress. Only one species showed a significant, but small (3%), increase in body mass in winter, suggesting only a minor role for winter fattening in any such seasonal metabolic adjustments in the species studied. The findings contrast with those for some passerines overwintering in the north temperate zone, but the generality of these possible north-south differences needs further investigation.

Behavioral Energetics of Overwintering in the Rifleman, Acanthisitta-Chloris

The role of behavioural adjustments in meeting increased daily energy requirements in winter was investigated in rifleman, Acanthisitta chloris, inhabiting lowland forest in South I., New Zealand, by comparing their population density, time-activity budget and foraging behaviour in autumn and winter. Rifleman foraged for 83% of daytime in both seasons. The combined effects on the birds' winter energy budget of increased thermoregulation costs and the shorter daylength for foraging were at least partly offset by an estimated 23-29% decrease in the amount of energy expended daily on activity and a 78% increment in prey caught per day. The reduced energy expenditure on activity resulted from rifleman spending less time on expensive flying and more time roosting. The increase in prey capture rate may have stemmed from a 35% seasonal reduction in the birds' population density and reduced prey mobility at lower ambient temperatures. Marked sexual size dimorphism was not reflected in gender differences in activity budgeting or prey capture rate, but the sexes differed in their relative use of foraging substrates. Rifleman showed few seasonal changes in daily activity rhythm or microhabitat use. The behavioural energetic overwintering tactics of rifleman are compared with those of other Australasian and north temperate zone land-birds.

Water-Vapor Conductance and Shell Characteristics of Superb Lyrebird Eggs

Superb lyrebirds exhibit a suite of breeding characteristics (a long incubation period, low incubation constancy, use of an enclosed nest, and winter nesting) which might cause an unusual pattern of gas exchange in the egg during incubation. This possibility was investigated by determining the egg's natural rate of water loss during incubation and its water vapour conductance, and by measuring shell parameters which influence these properties. The estimated fractional weight loss of the 61,5-g egg during incubation was 16%. This was similar to that in other species, as was the calculated water vapour pressure difference across the shell (27 Torr=3.6 kPa). The mean rate of water loss (194 mg day-') and the mean water vapour conductance (7.08 mg day-' Torr-' =53.23 mg day-' kPa-') of the egg were, however, relatively low. True shell thickness averaged 218 �m and pore density was 50-56 pores per square centimetre. Pores were unbranched and relatively evenly distributed. The fairly standard fractional weight loss over the 50-day incubation period resulted from the egg's low water vapour conductance which, in turn, stemmed mainly from a comparatively low pore density. It was concluded that the protracted incubation period, resulting from the low incubation constancy at low ambient temperatures, was probably the principal influence on the evolution of the small pore area and low water vapour conductance of the lyrebird egg.

Time-Energy Budgets During Reproduction and the Evolution of Single Parenting in the Superb Lyrebird

Estimated expenditures on brood-care by unassisted female superb lyrebirds, obtained through time-energy budgeting, were compared with published values for other bird species. With the exception of nestbuilding, estimated daily expenditures were relatively low, due mainly to the small brood size and low level of parental attentiveness. It is suggested that the traits which reduce daily brood-care expenditures, particularly the small brood size and extremely slow growth rate, may have evolved as adaptations which enabled deserted females operating close to maximal capacity to cope with single-parenting. Male parental involvement could probably increase the growth rate of the young, but not brood size; moreover, egg- laying was sufficiently asynchronous to afford multiple mating opportunities to parentally emancipated males. However, the slow growth rate of the young results in relatively large overall brood-care expenditures for females. Investments by males of up to 50% of daylight hours and 45% of BMR on singing at the height of the mating season were comparable with those of partially emancipated, polygynous males of other species. They probably reflect the high level of competition to control good display areas and to advertise status and quality to widely spaced females.

Weight Changes and the Mode of Depot Fat Accumulation in Migratory Short Tailed Shearwaters

The time course of fat deposition in short-tailed shearwater breeding adults, immatures and chicks was determined by monitoring weight changes at the breeding site, and the relative importance of de novo fatty acid synthesis and direct incorporation of fatty acids from the diet was assessed by assaying enzymes associated with hepatic lipogenesis. Extensive fat deposition occurred only in the chicks during development, and all age classes deserted the breeding colony with relatively small reserves of depot fat. The absence of major changes in activities of hepatic lipogenic enzymes in the period between first land- fall in September and breeding site desertion indicates that fat deposition in all age classes occurs mainly through direct incorporation of fatty acids from the diet. Ecological and energetic implications of these findings are discussed.

Spatial organisation in small flocks of domestic fowl

Abstract

(i) Spatial organisation was studied in small flocks of domestic fowl to elucidate its underlying mechanisms and provide a basis for future comparative analyses. (ii) Approach-tolerance distance values were obtained in a non-competitive feeding and a roosting situation. (iii) A zone of variable width across which the likelihood of approach eliciting agonistic response increased centripetally was observed around feeding birds. No sexual difference in zone width was noted, and tolerance of approach was great. (iv) No indication of constant Individual Distance in roosting birds was obtained, though spatial adjustment following agonistic interaction was observed. Clumping was common. (v) Activity-dependent variability in spatial organisation was described and correlated with the distribution of aggressive behaviour. (vi) It was postulated that the state of dispersion during specific activities was explicable in terms of the interaction of the opposed tendencies to congregate and aggregate and to react aggressively when approached. (vii) The nature and distribution of clumping and allopreening responses were described, and their causation and function discussed.

Potential ethological isolating mechanisms and assortative mating in the domestic fowl

Abstract

(1) Potential ethological isolating mechanisms were observed between breeds and strains of domestic fowl. (2) Brown and White Leghorn females exhibited homogamy, but females of a Broiler strain showed a preference for Breeding Line Brown Leghorn males, which bear a close phenotypic resemblance to the Red Jungle fowl (Gallus gallus spadiceus). (3) Observations indicated that females discriminated between males on physical characteristics rather than quantitative differences in male courtship. (4) In a ''choice-situation'', males which had been reared with own-breed females courted caged own-breed hens significantly more than others. Males reared with their own and other breeds showed only weak own-breed preferences, and in two cases, heterogamy was observed. (5) Males apparently discriminated between females on visual cues, particularly female plumage colour. (6) Assortative mating within a single line was also observed, females preferring some males to others. Quantitative differences in male courtship were not important in this respect. (7) In tests of short duration, males did not exert preferences for individual hens of a single line. (8) A sequential analysis of the courtship of the Brown Leghorn cock revealed that two displays were important in evoking female solicitation, namely the waltz and the rear approach. Three other displays were interpreted as increasing sexual arousal in the female. (9) The evolutionary significance of some of the results is briefly discussed.