Extensive human presence at an early age of ostriches improves the docility of birds at a later stage of life

Text Mining and Topic Analysis for Ostriches' Welfare Based on Systematic Literature Review from 1983 to 2023

Ostriches can be utilized as multipurpose animals suitable for producing meat, eggs, feathers, and leather. This growing interest in ostrich farming leads to an increased demand for comprehensive information on their management. But, little attention is paid to the consequences for their welfare. The study aimed to perform a research literature analysis on ostriches' welfare using the text mining (TM) and topic analysis (TA) methods. It identifies prevailing topics, summarizes their temporal trend within the last forty years, and highlights potential research gaps. According to PRISMA guidelines, a literature exploration was achieved using the Scopus® database, retaining keywords about ostriches' welfare. Papers distributed in the English language from 1983 to 2023 were included. Descriptive statistics, TM, and TA were applied to a total of n. 122 documents included. The findings revealed an increasing trend in research records since 1994. TM recognized the terms with the highest weighted frequency and TA identified the main topics of the research area, in the following order: "health and management", "feeding and nutrition", "welfare reproduction", "egg production", and "welfare during transport". The study confirms the increased focus on ostriches' welfare but shows that further studies are required to ensure the welfare of this species.

Genetic parameters and correlations for behavioural response traits towards humans in South African Black ostriches

1. The aim of this study was to estimate heritability and genetic correlations, first among behavioural responses of juvenile South African Black ostriches towards humans and secondly with slaughter weight and skin traits.2. Behavioural traits, such as willingness of the birds to approach humans, keeping a distance from the human observer and allowing touch interactions by a human were recorded (n = 1012 birds). In addition, slaughter weight, skin size, scores for nodule size, nodule shape and the presence of hair follicles were recorded.3. Single- and multi-trait animal model analyses performed on the data using ASReml4 revealed high heritability estimates of 0.44 for allowing touch interactions and 0.48 for both willingness to approach and keeping a distance from the human observer. In addition, significant genetic correlations among behavioural response traits were estimated, ranging from -0.99 between keeping a distance and willingness to approach the human observer, to 0.87 between allowing touch interactions and willingness to approach the human observer.4. In contrast, genetic correlations of behavioural response traits with most slaughter and skin traits were low, variable, and not significant. The exception was hair follicle score, which appeared to be unfavourably correlated with key behavioural traits.5. This study suggested that the temperament of ostriches could be improved by selection of birds that demonstrate willingness to associate with humans without compromising slaughter weight or skin traits.

Mass Sperm Motility Is Correlated to Sperm Motility as Measured by Computer-Aided Sperm Analysis (CASA) Technology in Farmed Ostriches

Semen analyses have gained momentum in various livestock industries. However, in farmed ostriches, semen analysis is still in its experimental stage, and males are not screened for sperm quality before breeding. This study investigated the correlations between computer-aided sperm analysis (CASA) technology and the traditional, yet affordable, mass sperm motility score. Semen was collected from nine South African Black ostrich males (mean age ± SD: 5.25 ± 1.21 years), using the dummy female method for 5 consecutive days monthly, for 8 months. Mass sperm motility scores were recorded on a scale of 1−5 (1: little to no sperm movement; 5: rapid sperm movement). The CASA traits recorded were: total motility (MOT), progressive motility (PMOT), curve−linear velocity (VCL), straight-line velocity (VSL), average path velocity (VAP), amplitude of lateral head displacement (ALH), linearity (LIN), straightness (STR), wobble (WOB), and beat-cross frequency (BCF). The results revealed positive correlations between mass sperm motility and PMOT, MOT, VCL, and VAP ranging from 0.34 to 0.59 (p < 0.0001). In contrast, negative correlations were recorded between mass sperm motility and LIN, STR, and BCF, with correlations ranging from −0.20 to −0.39 (p < 0.0001). VSL, ALH, and WOB were not correlated to mass sperm motility (p > 0.05). Ostrich farmers may thus be able to evaluate sperm motility reliably and potentially select breeding males by using the affordable mass sperm motility scoring method. Determining the correlation between these methods and fertility after artificial insemination or natural mating is however needed.

The effect of early experiences in Barn Owl (Tyto alba) behaviour. Acquisition-expression time of neophobia and filial imprinting. Implications for management and conservation

In birds, early experiences determine the later behavioural phenotype of individuals and their way of adapting to the challenges they encounter in their environment. We investigated how the degree of exposure of barn owl chicks to humans and their biological parents influenced their behavioural response to humans and different environments. Only the treatment groups raised by human beings, or those that remained for less time with their biological parents (15 days posthatching), learned to fly towards their trainer. However, the two groups of chicks that were raised the longest by their biological parents (20 and 25 days) never flew towards their trainer. In these last groups, the filial imprint was shown not to be able to be reversed. Neophobia was estimated to emerge between 17 and 19 days of age, as barn owls were able to recognize the environment in which they were habituated, showing fear of a new environment. Birds were able to recognize the person who raised them and objects with which they had been raised. The results obtained in this work can help to establish breeding protocols in this and other species of birds of prey, which improve their adaptability to the environment where they will live, whether in captivity or in the wild.

Ostrich ejaculate characteristics and male libido around equinox and solstice dates

The study evaluated the effect of time of the year in which changes in photoperiod occurs on ostrich semen characteristics and male libido. Semen was collected for 5 days before, on and 5 days after winter solstice (21 June 2016), spring equinox (22 September 2016), summer solstice (21 December 2016) and autumn equinox (20 March 2017) in the southern hemisphere. Semen was collected from 10 South African Black ostrich males (average age ± standard deviation; 4.5 ± 2.27 years) using the dummy female. Semen volume, sperm concentration, total sperm per ejaculate, sperm motility traits, percentage of normal sperm, head and tail abnormalities and percentage of affected sperm in the hypo-osmotic swelling test (HOS) were evaluated. Male libido defined as the willingness of males to mount the dummy female was also recorded. Semen samples collected around summer solstice, spring and autumn equinox were higher in sperm concentration and sperm output compared with winter solstice (P < 0.05). Study periods did not influence semen volume, sperm motility traits, the percentage of normal sperm, head abnormalities and HOS. Tail abnormalities were higher around winter solstice than around spring equinox (P < 0.05). Male libido and the success of semen collection were significantly higher around spring equinox (P < 0.05). Changes in photoperiod in the southern hemisphere do not affect semen production in ostriches. However, high sperm output and male libido around spring equinox and summer solstice dates suggest that these periods may be preferred for semen collection for artificial insemination and storage purposes.

The Effect of Behind-The-Scenes Encounters and Interactive Presentations on the Welfare of Captive Servals (Leptailurus serval)

Simple Summary

Live animal encounter programs are an increasingly popular occurrence in the modern zoo. The effects of such encounters on program animal welfare have not been studied extensively to date. The aim of this study was, therefore, to explore animal welfare effects associated with encounter programs in a small felid, the serval, which is commonly involved as a program animal in zoos. Specifically, this study investigated how serval behaviour and adrenocortical activity (level of faecal cortisol metabolites) were affected by short-term variations in encounter frequency. Over the course of the study, the frequency of encounters was manipulated so that servals alternated between four different treatments, involving interactive presentations, behind-the-scenes encounters, both activities combined, or no interaction at all. The cats exhibited a significant reduction in stereotypic pacing on weeks when participating in interactive presentations, or the two activities combined. However, behavioural diversity (total number of behaviours exhibited) was strongly reduced on weeks when cats participated in both activities. Adrenocortical activity did not vary significantly between treatments. The reduction in stereotypic pacing suggests that involvement in an encounter program may exert a positive short-term welfare effect on the individual servals. A reduction in behavioural diversity, which was not considered a negative welfare effect in the short term, may, however, warrant some need for caution if a more frequent encounter program was to be implemented long-term. These findings contribute to the current knowledge of visitor–animal interaction in zoo-housed felids, which is very limited to date, and could also provide valuable guidance to zoo professionals that are currently engaging in an encounter program with servals or planning on implementing such a program in the future.

Abstract

The serval (Leptailurus serval) is a small African felid that is well represented in zoos and often serves as an animal ambassador in encounter programs with zoo visitors. The impact on serval welfare in relation to such programs has not been investigated to date, and the aim of this study was to assess short-term welfare effects of varying levels of visitor interaction in two captive servals. Weekly blocks of four different treatments were imposed three times on each animal over 12 weeks, and the treatments involved (1) Presentations (serval undertaking a routine training session in a designated presentation space, typically attracting high visitor numbers), (2) Behind-the-scenes (BTS, a close encounter allowing a small group of visitors to interact closely with the cat in its enclosure), (3) Presentations and BTS combined, and (4) No visitor interaction. Serval activity budgets as well as behavioural diversity were created from behaviours observed from Close Circuit Television (CCTV) footage during four daily recording sessions per animal over three consecutive days per treatment, using instantaneous scan sampling every 60 s. Individual faecal samples were collected daily to monitor changes in faecal glucocorticoid metabolite (FGM) concentration. Results indicate that the mean number of scans with stereotypic pacing was significantly reduced (p = 0.01) during Treatments 1 and 3, when cats participated in presentations only, or the two activities combined. Conversely, a significant reduction in behavioural diversity (p < 0.001) was observed when cats participated in Treatment 3, i.e., cats expressed fewer behaviours when interaction with visitors was more frequent. FGM concentrations did not vary significantly with treatment (p > 0.05). Given the reduction in stereotypic pacing, these findings suggest that involvement in an encounter program appears to exert an overall positive short-term welfare effect on the individual servals in this study. Although a reduction in behavioural diversity was not considered a negative welfare effect in the short term, potential long-term negative welfare effects resulting from a more frequent encounter program could not be ruled out in the present study.

The Visitor Effect on Zoo Animals: Implications and Opportunities for Zoo Animal Welfare

Simple Summary

Research has shown that an animal’s welfare is highly dependent on how various individual animal factors (e.g., species traits, genetics, temperament and previous experience) interact with environmental features (e.g., social grouping, enclosure design and sensory environment). One prominent feature of a zoo’s environment is the presence of visitors. Decades of research on the visitor effect in zoos has demonstrated that visitors can have negative, neutral or positive impacts on zoo animal behaviour and welfare. This paper reviews the literature on the implications and potential opportunities of human–zoo animal interactions on animal behaviour and welfare, with the aim of stimulating interest, understanding and exploration of this important subject.

Abstract

Achieving and maintaining high standards of animal welfare is critical to the success of a modern zoo. Research has shown that an animal’s welfare is highly dependent on how various individual animal factors (e.g., species traits, genetics, temperament and previous experience) interact with environmental features (e.g., social grouping, enclosure design and sensory environment). One prominent feature of the zoo environment is the presence of visitors. Visitor contact can be unpredictable and intense, particularly in terms of auditory and visual interaction. Depending on an animal’s perception of this interaction, visitors can have either negative, neutral or positive impacts on zoo animal behaviour and welfare. This paper reviews the literature on the implications and potential opportunities of human-zoo animal interactions on animal behaviour and welfare, with the aim of stimulating interest, understanding and exploration of this important subject. The literature to date presents a mixed range of findings on the topic. It is possible this variation in the responses of zoo animals to visitors may be due to species-specific differences, the nature and intensity of the visitor interactions, enclosure design, and individual animal characteristics. Analysing these studies and better understanding animal preferences and motivations can provide insight into what animals find negatively and positively reinforcing in terms of visitor contact in a specific zoo setting. This understanding can then be applied to either safeguard welfare in cases where visitors can have a negative impact, or, conversely, it can be applied to highlight opportunities to encourage animal-visitor interaction in situations where animals experience positive emotions associated with visitor interaction.

The Effect of Extensive Human Presence at an Early Age on Stress Responses and Reactivity of Juvenile Ostriches towards Humans

The effect of extensive human presence and regular gentle handling performed at an early age (0⁻3 months old) on stress responses and reactivity of juvenile ostriches towards humans was investigated. A total of 416 ostrich chicks over two years were exposed to one of three treatments for three months after hatching; namely, Human Presence 1 (HP1, N = 144): extensive/prolonged human presence with physical contact (touch, stroking), gentle human voice, and visual stimuli; Human Presence 2 (HP2, N = 136): extensive/prolonged human presence without physical contact, but with gentle human voice and visual stimuli; and the Standard treatment (S, N = 136): human presence limited to routine feed and water supply as a control. At 7.5 months of age, the plasma heterophil/lymphocyte (H/L) ratio was measured before and 72 h after feather harvesting and feather clipping to determine acute stress responses, while chronic stress was measured by quantification of corticosterone (CORT) concentrations in the floss feathers of the birds. Birds' behavioural response towards a familiar or an unfamiliar handler was evaluated at 12 months using docility and fear tests, and through behavioural observations conducted on random days between the ages of 8⁻13 months. Willingness to approach, and to allow touch interactions, aggressiveness, and exhibition of sexual display towards the handler, was recorded. No difference in the H/L ratios before and after feather harvesting and clipping was observed in HP1 birds, whereas H/L ratios showed a significant increase 72 h post feather harvesting and clipping in HP2 and S birds (p < 0.05). Birds from the S treatment exhibited a significantly (p < 0.05) higher feather CORT concentration compared with HP1 birds, while HP2 birds had intermediate responses. Birds' reactivity towards humans and temperament as evaluated using behavioural observations, docility, and fear tests was not affected by treatment (p > 0.05). However, HP1 and HP2 birds were more inclined (p < 0.05) to approach a familiar rather than an unfamiliar handler during the behavioural observations, indicating an ability to distinguish between a familiar and an unfamiliar handler. Overall, the results indicate that early gentle human interactions with ostrich chicks can be beneficial in reducing physiological stress sensitivity later in life and facilitate the ability of ostriches to distinguish between familiar and unfamiliar handlers.

Mineral profiling of ostrich (Struthio camelus) seminal plasma and its relationship with semen traits and collection day

Successful assisted reproduction techniques, with specific focus on in vitro semen storage for artificial insemination, are dependent on certain key elements which includes the biochemical profiling of semen. The objective of this study was to complete an ostrich seminal plasma (SP) evaluation by inductively coupled plasma mass spectrometry (ICP-MS) among seven males at different daily intervals (day 1, 3, 7, 11, 15, 19, 21, 23, 25, 26, 27, 28) for a period of 28 days during spring (August to September) for mineral profiling. The effect of collection day and male on sperm concentration, semen volume and seminal plasma volume, was explored as well as the relationships amongst these specific sperm traits and SP minerals. Variation amongst SP mineral concentrations, accounted for by the fixed effects of sperm concentration, semen volume, seminal plasma volume, collection day and male, ranged from 18% to 77%. Male had the largest effect on variation in SP minerals, namely: phosphorus (P), potassium (K), calcium (Ca), sodium (Na), boron (B), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), molybdenum (Mo), barium (Ba), arsenic (As) and selenium (Se). Sperm concentration instigated fluctuations of P, magnesium (Mg), B, zinc (Zn), Fe, aluminium (Al), Se, manganese (Mn) and lead (Pb). Semen volume had an effect on Na, K, B, Pb and Ba while seminal plasma volume only influenced variation in Na. There were fluctuations among collection days of specific micro minerals, Ni and Mo, with initial Ni concentrations being relatively greater and Mo at lesser concentrations. Semen volume, seminal plasma volume and sperm concentration varied amongst males. Sperm concentrations during the initial collection days, 1 and 3, were less than that for days 7 to 28. Significant variation of SP minerals and sperm characteristics among ejaculates and males suggest an association of these specific elements with sperm function and are, therefore, considered to be of potential importance to success of assisted reproduction technology for the ostrich. The relationship amongst sperm concentration and collection day confirms the need to conduct an initial period of collection to stabilise a greater sperm concentration to optimise sperm numbers for artificial insemination purposes.