Behavioural reactivity of two lines of South African Merino sheep divergently selected for reproductive potential

The behavioural reactivity of two divergently selected lines of South African Merino sheep for an increased (HL: N = 1187) and reduced (LL: N = 285) number of lambs weaned per ewe mated was investigated using a docility test and a ‘scale’ test. The objective of this study was to determine whether these two lines, which differed significantly in terms of reproduction performance, would also react differently when exposed to novel and challenging situations. In the first test, an individual animal was moved to the test pen by an experienced handler then an unfamiliar or familiar human entered the test pen and tried to encourage the animal to move into a marked area for 3 min. The test was terminated if the animal could not be moved within 3 min, came out of the marked area or if the animal could be contained in the marked area for 30 s (successful test). The latency of the animal to enter and time contained in the square area was recorded as well as whether the animal was bleating or urinating/defecating during the test. No difference was found between production lines and handler in terms of the success of the test and latency to enter (P > 0.05). LL sheep were however contained for longer and bleated more than HL sheep (P < 0.05). Sex differences were also observed, with ewes being more difficult to successfully contain and bleating more than rams, especially when exposed to an unfamiliar human (P < 0.05)

Using Technology to Serve the Agricultural Community in the Western Cape Province of South Africa

Abstract The Western Cape Department of Agriculture has a team of agricultural experts using novel approaches to address the challenges faced by South African agriculture. The objective of this paper is to describe some of the innovative research and technologies, and methods of technology transfer, used to better serve the agricultural community. The spectrum of technologies implemented includes new research on breeding (biotechnology); new approaches to conservation agriculture; remote sensing satellite and spatial information for improved decision making, such as the spatial intelligence project and FruitLook; Agricultural Integrated Management System; and technology to manage and disseminate information, such as smart (digital) pen and paper technology and Agri-Touch. The paper is an introduction to some of the cutting-edge research and technologies and new methods of communication, information dissemination and decision making support that serves the agricultural community in a tangible way. Keywords: Technology, Biotechnology, Conservation Agriculture, Remote Sensing, Information Disseminatio

A morphological classification of sperm defects in the ostrich (Struthio camelus)

Commercial ostrich farming is constrained by the absence of a formal animal recordingand evaluation scheme as well as by current farming practices. Artificial insemination mayhave an important role in overcoming these limitations, but requires a thorough knowl-edge of sperm morphology. Although the morphological characteristics of normal ostrichsperm have been documented, little information is available on the incidence and struc-tural peculiarities of defective sperm in this species. Semen smears were prepared fromthe ejaculates of five ostriches (Struthio camelus), stained and evaluated. Defects wereobserved in 17% of sperm studied. Tail defects constituted the most common anomaly.Various forms of bending were the main tail defect, ranging from gentle to acute bends ofthe principal piece, Dag-like coiling at the head base, sharp reflexes of the midpiece as wellas coiling of the endpiece. In contrast, head defects were comparatively low in frequency,with macrocephalic sperm being the defect most frequently observed in this region. Bent,microcephalic, acephalic and round sperm heads were also noted but were few in num-ber. Cytoplasmic droplets occurred frequently in the fixed smears, either associated withthe sperm or as free-lying droplets. A small percentage of sperm with multiple defectswas recorded. The incidence of morphologically normal sperm in ostrich semen comparedfavorably with that reported in emu semen, another commercially farmed ratite. However,the range of defects differed appreciably between the two species. Sperm tail anomalieswere the most frequent category in the ostrich, whereas head defects comprised the maingrouping in the emu.Partial funding for the project was provided by the Western Cape Agricultural Research Trust, the South African Ostrich Business Chamber and the National Research Foundation (NRF) of South Africa through their THRIP program.http://www.elsevier.com/locate/anireproscihb201

The effect of extensive human presence at an early age on stress responses and reactivity of juvenile ostriches towards humans

CITATION: Muvhali, P. T., et al. 2018. The effect of extensive human presence at an early age on stress responses and reactivity of juvenile ostriches towards humans. Animals, 8(10):175, doi:10.3390/ani8100175.The original publication is available at http://www.mdpi.comPublication of this article was funded by the Stellenbosch University Open Access Fund.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.https://www.mdpi.com/2076-2615/8/10/175Publisher's versio

Mate choice and immunocompetence in ostriches (Struthio camelus)

Thesis (PhD (Botany and Zoology))—University of Stellenbosch, 2009.Females of many bird species prefer to mate with males exhibiting elaborate ornamentation, which serves as an indicator of male quality. Such ornaments, called secondary sexual traits, could act as signals to females that males could confer direct and/or indirect genetic benefits (when offspring inherit superior genes), on offspring. In particular, it has been suggested that these signals relate to male ability to resist infections, as only high quality individuals are able to invest both in high immune defence and elaborate ornament expression. The ostrich (Struthio camelus) is the largest living bird and is a member of the family of flightless birds, the ratites. They are sexually dimorphic, males displaying black plumage, and a pink-coloured neck and bill; whereas females display dull-brown plumage (both sexes have white feathers). Little is known about the mating system of ostriches: they are promiscuous and in the wild, males and females have multiple partners. The communal nesting system of ostriches is unique in that only the major female and major male provide parental care, in the form of incubation and guarding the offspring until independence. Furthermore, a remarkable feature of cohorts is that offspring may differ greatly in size, and these size differences are likely to have a genetic basis arising from differing parental genotypic differences. As a trade-off between immune response and life-history traits has been documented in various bird species, I examined the relationships between male secondary sexual traits (and specifically colouration) and maternal investment; levels of immunocompetence in both parents and chicks; and chick growth. This study showed that females invest more at the egg stage in response to traits involved in the male courtship display: the colour of the neck, white and black body feathers, and the brightness of black feathers. As these traits, which are exposed during the courtship display as well as during male-male interactions, were related to male immune responses, I suggest that only high quality males will be able to display their condition optimally. Chicks with higher growth rates were found to have intermediate responses to stimulation of their humoral immune system with diphtheria and tetanus vaccines, suggesting that not only fitness benefits, but also costs are associated with mounting an immune response; and that variation in humoral responses and growth rates relates to how individuals trade off these costs and benefits. In addition, chick humoral responses were found to be related to the humoral response of both parents, but through different antibody responses (maternal responses to tetanus and paternal responses to diphtheria), suggesting that this component of the immune system is heritable. As the colouration of white feathers predicted chick growth rates, as well as a male’s ability to raise an antibody response, I suggest that this visual cue could serve as a signal to females of male humoral immunocompetence, therefore forming the basis of mate choice whereby females could increase the fitness of their offspring through higher growth rates

Investment in eggs is influenced by male coloration in the ostrich, Struthio camelus

Life history theory predicts that females should modify their investment in a particular breeding attempt according to the likelihood of its success, as the investment of females in reproduction is typically higher than that of males. The ostrich mating system is promiscuous, and is thus a particularly interesting one in which to investigate differential investment by the sexes. To date, there has been no evidence that female ostriches discriminate between males as potential mates, but the degree of dimorphism in this promiscuous species and the variation in chick size within clutches suggest that differential maternal investment is likely. We investigated the relationship between egg mass and coloration of the feathers, bill, neck and legs of 15 male ostriches, maintained in a breeding flock at an ostrich farm in South Africa. Paternity was determined using microsatellite markers. We found that the colour of the neck, white and black body feathers, and the brightness of black feathers, predicted egg mass. These traits are exposed during the male courtship display, so we suggest that these visual cues influence the degree of maternal investment in eggs through their influence on female perception of mate quality. © 2009 The Association for the Study of Animal Behaviour.Link_to_subscribed_fulltex

Male coloration reveals different components of immunocompetence in ostriches, Struthio camelus

It has been suggested that secondary sexual ornamentation signals male ability to resist infections, as only high-quality individuals are able to invest both in high immune defence and elaborate ornament expression. Such ornaments could thus serve as indicators of male quality and could be used by females in choosing mates. Ostriches are sexually dimorphic with regard to coloration of their feathers, bill, neck and legs, and have a promiscuous mating system, with a high degree of reproductive skew, particularly in males. We investigated the relationship between the coloration of the feathers, bill, neck and legs of 15 male ostriches, maintained in a breeding flock, and the cell-mediated (measured using a phytohaemagglutinin (PHA) injection) and humoral components of their immune systems, as well as their heterophil: lymphocyte ratio. We found that male responses to PHA injection and humoral responses to tetanus were predicted by leg coloration, humoral responses to diphtheria were predicted by white feather coloration, and the heterophil: lymphocyte ratio was related to bill coloration. These traits, which relate to male immune capacity, are exposed during male-male interactions and courtship display, so we suggest that these visual cues could provide valuable information on male quality to females (as well as rival males), forming the basis of mate choice in this species. (C) 2009 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved

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 &plusmn; SD: 5.25 &plusmn; 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&ndash;5 (1: little to no sperm movement; 5: rapid sperm movement). The CASA traits recorded were: total motility (MOT), progressive motility (PMOT), curve&ndash;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 &lt; 0.0001). In contrast, negative correlations were recorded between mass sperm motility and LIN, STR, and BCF, with correlations ranging from &minus;0.20 to &minus;0.39 (p &lt; 0.0001). VSL, ALH, and WOB were not correlated to mass sperm motility (p &gt; 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

Growth rate and hatching date in ostrich chicks reflect humoral but not cell-mediated immune function

A tradeoff between immune response and life history traits, in particular growth rate, has been documented in various bird species. Ostriches are fast-growing birds and a typical feature of cohorts is that offspring often differ greatly in size. We investigated the relationship between hatching date and growth rate of chicks and both cell-mediated (measured using a phytohaemagglutinin (PHA) injection) and humoral immune responses in ostrich chicks maintained on a research farm. Chicks with higher growth rates had intermediate responses to both diphtheria and tetanus toxoids. By contrast, no relation between growth rates and responses to PHA injection were found. We conclude that chick growth rate variation may be explained beyond a certain threshold by a tradeoff between the humoral response and growth. Both responses to PHA injection and humoral responses in chicks were found to decrease with chick hatching date. Within the context of ostrich farming, these results could partially explain size variations observed in cohorts of chicks, as well as high mortality rates during their first 3 months of age. © Springer-Verlag 2009.Link_to_subscribed_fulltex