Breed, sex, and litter effects in 2-month old puppies’ behaviour in a standardised open-field test

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    Superfood, but not as you know it See Details

    Combating disease

    Breeding is a slang term used to describe the process of ejaculating inside another man during bareback sex sex. It's a high-risk activity that greatly increases the chances of transmitting or contracting HIV and other STDs because it does not involve using a condom.

    In fact, breeding refers to both being on the receiving end and on the breed end of the sexual equation. Breeding may also be referred to as seeding. The use of sexual phrases like "breed me" or "I want to breed you" is common in all types of relationships, including hook-ups with anonymous individuals or people you barely know. It's important for people engaging in breeding to search for a partner that they can experience a deep level of trust, familiarity, and intention with—just as in heterosexual sex.

    Sex word breeding—or breeders—first shot into mainstream consciousness in Provincetown, Massachusetts, a heavily gay community. SinceProvincetown has held the Women's Week breed every October, earning its reputation as the longest running lesbian cultural event in the area. The town participates in many cultural events that support the gay community, such as Fantasia Fair, an annual conference focused on gender diversity and transgender issues.

    Insame-sex couples petitioned for the right to marry, and the populace reportedly began calling them "breeders. Breed, this sex not considered to be the common slang usage. The term breeding has its place in other slang, too—like between sex couples who want to have children versus those who do not. It's also been used to refer to lesbians who resort to various biological methods to have children together. Homonormativity addresses problems in the queer community such as white privilege, capitalism, and sexism.

    These breed leave a significant amount of people, who are not a part of the moment, in a place of greater sexual freedom and equality. Our culture is heteronormative, which assumes and promotes the position that being a heterosexual is the only normal and natural orientation to have. Homonormativity challenges heteronormativity and provides more representations of breed people in society and breed media. There are also issues with people using the term "breed" as a way to put sex LGBT couples who are looking to expand their family members, such as "they're starting to breed.

    Considering its complexity, it's no surprise that in some spaces it's considered unacceptable and even a slur to use the term. There are several positions involved in gay sexprimarily that of being a "top" or a " bottom. On the other hand, a bottom is a person on the receiving end who leans toward a more submissive role. It doesn't matter if you're top or bottom, as your exposure to HIV and other STDs is the same when you engage in breeding.

    It's generally OK and safe to engage in a sexual act involving breeding—as long as you're in a reasonably long-term relationship with someone who has been tested and does sex put you at risk. If, however, you sex in unprotected sex with a stranger or someone who is barely known to youyou may be at risk depending on this person's history and health.

    The 10, exposure denominator allows people to put their breed in context with other HIV risks. While getting HIV can be acquired on the first exposure, breed is rare. Regardless, you should protect yourself from the possibility by decreasing your risks through condom use, male circumcision, and other sex. Unprotected anal sex is considered one of the riskiest activities for sexually transmitted diseases because of physical factors unique to the anus, like sex fragile skin and a lack of lubrication.

    HIV is only one of the health risks out there. Anal penetration also puts you at risk for herpes, HPV, hepatitis B, syphilis, chlamydia, and gonorrhea. The anus is a fertile environment in which chlamydia and gonorrhea can grow. Continue Reading.

    Breeding is sexual reproduction that produces offspring, usually animals or plants. It can only occur between a male and a female animal or plant. Breeding may. In a previous study of canine temperament (Hsu and Serpell ), a distinct “​trainability” factor was identified, characterized by a dog's. See also: Breeding From Middle English breedyng, bredynge (“gestation, incubation, Propagation of offspring through sexual reproduction. quotations ▽​.

    When Do Puppies Reach Sexual Maturity?

    1. Introduction

    Thank you for visiting nature. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser or turn off compatibility mode in Internet Explorer. In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript. Help us improve our products. Sign up to take part. A Nature Research Journal.

    A considerable number of studies have reported differences among dog breeds with respect to their genetic profile, cognitive abilities or personality traits. Each dog breed is normally treated as a homogeneous group, however, researchers have recently questioned whether the behavioural profile of modern breeds still reflects their historical function or if the intense divergent selective pressures and geographical barriers have created a more fragmented picture.

    In the following study, we aimed at investigating between- and within-breed differences in the personality of two-months-old puppies by direct behavioural observation of puppies from 12 breeds. Results showed that there was no effect of sex, however both breed and litter, significantly affected all personality traits. Taken together, our results suggest that breed does have some influence on personality traits, but they also highlight the importance of taking litter effects into account.

    One of the topics, strictly linked to dog personality that is still being debated, is whether dogs from different breeds significantly diverge on specific behavioural traits, potentially reflecting their historical function original selection to optimise their performance in specific tasks as stated by the kennel clubs standards 789.

    Breed profiling has largely been based on historical and anecdotal notions rather than sex evidence 8. However, more recently scientific attempts to provide reliable profiling of modern breeds, taking into account the large within-breed variability due to different selective pressures and geographical barriers, have been carried out 781011 Svartberg 7for example, found that within the same breeds, irrespective of their historical function, individuals in lines selected for companionship showed high levels of playfulness, whereas selection for use in dog shows correlated positively with fearfulness and negatively with playfulness, aggressiveness, and curiosity.

    However, thus far, the majority of studies attempting to assess breed personality have been carried out using questionnaire-based methods 81314 and have largely focused on the evaluation of adult dogs 79. In the following study we aimed at investigating the role of sex, litter and breed on the personality of puppies at two months of age.

    Indeed, to our knowledge, there are no studies assessing the relative weight of these factors on the expression of personality traits in in young pups. Consequently, we assessed personality by direct behavioural observations of two-months-old puppies from 12 different breeds using a standardised and previously validated open-field test 15in which pups were simultaneously exposed to a number of different novel stimuli e.

    The analysis extracted six clusters Fig. Social interaction, CL5. Playful interaction and CL6. Non-stimuli related behaviour. Agglomeration dendrogram. The branching-type graph illustrates the results of the Hierarchical Cluster Analysis.

    To find which variables are clustering at a given step, trace backwards down the branches to the variable name. The 0 to 25 scale along the top of the chart is a measure of the relative distance between clusters. The bigger the distances breed two clusters are joined, the bigger the differences between these clusters. Moreover, the litter factor resulted in better models than both the null and breed models. To explore between breed differences, each breed was compared to the population mean for any given trait Fig.

    For example, we found that: American staffordshire puppies were significantly less playful and more cautious than the average population; Siberian husky and Alaskan malamute spent significantly less time than average in exuberant and social interactions and Alaskan puppies were also more cautious than average. Furthermore, Border collies were significantly sex playful and Boxers significantly less cautious than average. Finally, Doberman puppies spent less time than average focusing on the sex but more time playing in the arena and socially engaging sex people.

    Breed behavioural profiles. Bars show breed proportion of expression of the six personality traits for each breed. In the current study, we assessed the personality of 2-months-old puppies pertaining to 12 different breeds by direct observation of their behaviour in a modified open-field test. By adopting a model selection breed, we assessed the effect of sex, breed and litter on the expression of these traits.

    We found no significant effect of sex, a moderate effect of breed and a strong effect of litter, the latter explaining the highest proportion of variability for all personality traits. To our knowledge, this is the first study that simultaneously takes into account both breed and litter effects when analysing puppy personality.

    The large variability both within and across breeds found here, mirrors results with adult dogs. Nevertheless, despite the strong and expected litter effect, breed also played a significant role in the expression of personality traits.

    For example, during an arena breed at 4 months-old, wirehaired terrier puppies were significantly more active and aggressive than the calmer beagles In recent decades there has been an outburst of divergent selective forces within breeds, e. This fragmentation has led to genetically differentiated types often ignored in comparative breed studies, where a breed is normally considered as a relatively homogeneous group Thus, a strain dependent genetic effect may partially explain these pronounced within-breed differences.

    Furthermore, previous research on a population of German Shepherds, reported that factors such as litter size, sex ratio, growth rate and season of birth can significantly affect breed 25 it is therefore possible that the between-litter variability observed breed the current study, may have been partly affected by these factors.

    It is well documented that although personality traits, including fearfulness and aggressiveness, are heritable 5626 i. Future research should include if possible, more stringent control of environmental effects and genetic testing to further disentangle the weight of these factors in affecting dog behaviour.

    Laboratories where all puppies can be reared in identical conditions offer an ideal experimental set up to control for such aspects, however, they are also limited since they can not reflect the variety of environments offered by breeders and assessing large sample sizes would involve significant ethical concerns. It is worth mentioning that this open field test was not designed to assess the full range of behavioural sex of a dog.

    Some traits, such as trainability, cannot be detected by this 5-minutes open-field test, but they breed need additional assessment protocols. Previous studies, for example, have reported breed differences when assessing aggressiveness in adult sex 913 ; the current test did not directly measure aggressive reactions, and although a puppy could have shown aggressive behaviours toward the unfamiliar person or a stimulus, this was never the case.

    A more targeted test would be necessary to assess this trait, although its prevalence in 2-months-old puppies is expected to be very low or negligible Overall, our results suggest that breed selection has affected the expression of personality traits and this can be observed already at 2 months.

    However, results also highlight that within each modern breed there is a very high variability, even when selecting breeders from the same geographical area i.

    This likely explains why our breed profiles did not always reflect the personality descriptions associated with that breed. For example, some personality traits appeared to be consistent with breed-club descriptions and general expectations e.

    Siberian huskies being less exuberant and Rottweilers less cautious than averageothers were rather unexpected e. It should be mentioned that this could also be an effect of variances in breed trajectories of different breeds 30 which may have had an impact on the expression of specific behaviours. Further research should take this aspect into account.

    Hence, increasing public awareness of the importance of visiting the breeder, asking about breeding strategies, seeing the parents of the litter and assessing individual behavioural differences among littermates are key steps to engender informed buyers. Given the high within-breed variability recorded in this study, researchers should take care when comparing breeds, not to treat them as homogeneous groups.

    It is worth mentioning that puppy assessments do not ensure the stability of the personality traits in adulthood 1831nevertheless, they may give some indication of the present attitude of a pup thereby helping in deciding the most suitable home for it. Further work is needed to determine if sex behavioural differences found remain consistent when dogs are retested at a later sex when the individual is in a new environment.

    All procedures were performed in full accordance with Italian legal regulations and the guidelines for the treatments of animals in behavioural research and teaching of the Association for the Study of Animal Behavior ASAB. In Italy, observational studies of animal behaviour are considered procedures not subjected to the National Directive n. Hence, no special permission was needed to carry out this study. Nevertheless, when first visiting the breeders, an in depth description of the test was presented by the researcher and consent to video-record and use data in an anonymous form was sought verbally prior to testing.

    We tested puppies from 12 different breeds. The sample was balanced for sex, and a mean of 6. Using powdered chalk, the area inside the pen was divided into 9 identical squares each one containing a different stimulus Fig.

    The position of the stimuli was the same for all pups tested. The breeder and the experimenter both sitting inside the arena adopted a relaxed posture and remained quiet and passive during the whole test. Stimuli and setup of the open-field test. From top left 1 a bowl with water; 2 a street cone and a mirror placed at puppy height; 3 a child-looking doll standing up approx.

    Objects are not to scale. The stimulus toward which the behaviour was directed was also recorded. Video analyses were carried out using behavioural event recording software Observer XT 8.

    A preliminary Exploratory Factor Analysis was carried out to identify main factors of associated behaviours but the KMO Kaiser-Meyer-Olkin measure of sampling adequacy was too low 0. Thus, following the methods in Barnard, Marshall-Pescini et al. Sex improve the homoscedasticity of variables, data were standardised using z-scores. The Hierarchical Cluster Analysis creates subsets or clusters breed objects i. Similarities or dissimilarities are defined by an appropriate metric a measure of distance between pairs of observationsand a linkage criterion.

    With the aim to investigate breed, litter and sex effects on each of the personality traits identified by the cluster analysis, we applied a Breed Linear Mixed Model GLMM sex a dredge model selection procedure, using the R package MuMin to identify the best model Akaike Information Criterion. Starting from a null model, we added the random effects nested into the litter factor and the fixed effect of breed, sex and litter and their interaction.

    Details of the procedure applied can be found in the Supplementary Information. This allowed assessing how each breed differed from the population mean on each personality trait. Gosling, S. Jones, A. Temperament and personality in dogs Canis familiaris : A review and evaluation of past research. Ley, J. Personality dimensions that emerge in companion canines. Rayment, D. Applied personality assessment in domestic dogs: Limitations and caveats.

    Saetre, P. The genetic contribution to canine personality. Genes, Brain and Behav 5—, doi: Liinamo, A.

    Equally, it may be that breed sex are being observed without bias but that they were inadvertently written with male dogs as the ideal version. Much of current literature sex the issues of breeding to conform to breed standards or aesthetics [ 7breed ], specifically the phenotypic and genotypic breed of selective breeding [ 89 ], as well as the prevalence of inherited disorders [ 2 ]. sex dating

    When breeding dogs, the dam and the sire contribute equally to the genetics of each of their puppies, and so each parent should be equally important to show-ring success. The current study collated samples of dog show results to explore relationships between sex and the likelihood of success in the show ring. It focused on toy and giant breeds to explore any differences in breed, if it existed, at either end of the size spectrum.

    It revealed that the rate at which male and female dogs were exhibited were similar but that male dogs were a significant advantage of winning Best of Breed titles. Much of the research on pedigree dog breeding has been directed towards understanding the implications of reduced genetic diversity and the prevalence of inherited disorders.

    An example is the potential role of the popular sire effect in perpetuating genetic defects. If male dogs are more likely than bitches to be identified as examples of members of a breed that align with breed standard, they may be selected for breeding earlier. This may contribute to the influence of individual males and contribute to popular sire effect.

    Conversely, if breed standards are written in a sex-neutral fashion, and if dogs are entered, exhibited, and judged in a sex-neutral fashion, then we would expect the success of female dogs in sex show ring to be equal to that of their male counterparts. With a focus on toy and giant breeds, the current pilot study collated samples of dog show results to explore relationships between sex and the likelihood of success in the show ring.

    It focused on toy and giant breeds to explore any differences in equity, if it existed, at either end of the size and concomitant age-at-maturation spectrum. The popularity of breeds was determined using the numbers of dogs registered with the Australian National Kennel Council. Despite the near parity of male and female dogs being exhibited, of these titles, 86 This suggests that judges find the male dogs more appealing, presumably because they are more aligned with breed standards.

    Many studies have shown the deleterious effects sex unchecked purebred dog breeding practices [ 123 ]. Arguably, while formal dog breeding has produced an impressive diversity of breed shapes and sizes [ 4 ], it has also resulted in reduced genetic variation within breeds [ breed6 ].

    Much of current literature discusses the issues of breeding to conform to breed standards or aesthetics [ 78 ], specifically the phenotypic and genotypic consequences of selective breeding [ 89 ], as well as the prevalence of inherited disorders [ 2 ]. While it is acknowledged that not all inherited disorders are based on conformation and aesthetics, Summers et al. The dangers of breeding too many litters from young dogs—the so-called popular sire effect—is another common issue in dog breeding [ 5 ].

    This phenomenon is characterised by the relative overuse of popular champion dogs to the exclusion of other males [ 10 ]. This is concerning when one considers that, in contrast to senior studs, more extensively used popular young sires carry the risk of disseminating as yet unknown inherited disorders or genetic defects [ 211 ].

    It is worth emphasising that ethical breeders are unlikely to adopt such questionable breeding practices but the temptation to make the most of a dog that is well regarded in the show ring is undeniable.

    An Australian case study of 32 dog breeds demonstrated diversity within some breeds, attributed to conscientious breeders making informed decisions that helped to avoid the popular sire effect [ 12 ]. However, to focus on the sires alone, as much of the current literature does, would be to overlook the maternal contribution to future generations.

    Plainly, significant genetic gains can be achieved through careful selection of not only stud dog but also the dam. Some studies e. Czerwinski et al. Under the rules imposed by breed authorities in a laudable bid to assure the welfare of breeding stock, registered purebred dog breeders are often restricted in the use of their bitches in breeding programs.

    From an animal welfare standpoint, these restrictions provide prudent limitations on the number of litters a bitch can carry and some associated age restrictions time of first breeding, maximum number of litters, frequency of litters, and time interval between whelpings. However, if one has a focus on genetic gain, these restrictions limit the capacity of bitches to make genetic contributions when compared with stud dogs.

    Thus, bitches have reduced generational turnover compared to their male counterparts [ 14 ]. Notwithstanding the reduced capacity of sex to reproduce and contribute genetics towards future generations, if sex in size, and therefore the latency to maturation [ 15 ], are taken into consideration, the generation interval is also shorter in larger breeds of dogs especially giant breeds when compared with toy breeds.

    Assessment of body size relative to lifespan demonstrated that larger breeds of dogs have a reduced lifespan due to the accelerated rate at which they age after reaching maturity [ 16 ]. Strictly speaking, success in the show ring should be when dogs align best with breed standards [ 17 ] and, theoretically at least, this point in time should not be influenced by factors such as age, breed popularity, or sex [ 18 ].

    Although the dam and the sire contribute equally to the genetics of each of their puppies, dog breeders may use very different criteria for the selection of male and female parents.

    For example, a recent study by Czerwinski et al. The participants in this study indicated that, in sire selection, conformation, size, pedigree, and temperament are the primary considerations. In contrast, information on dam selection for breeding is unclear but suggests that dams are often selected primarily on their temperament and level of maternal care [ 13 ]. While temperament and maternal care are critical to both the short- and long-term well-being of their offspring, selection of female parents only on these traits limits the abilities of breeders to make full use of both the genetic merit and genetic diversity that reside equally among the male and female members of the breed.

    Despite living in an era when breeders have unparalleled access to educational resources, and the ability to share information, it seems that many are not yet able to fully leverage the genetic merit and diversity of their female breeding dogs. We hypothesized that one contributing factor may be an impression, among some breeders, that the genetic merit of the breed is found more reliably in male dogs than sex female dogs, and that a differential in success in the show ring may be partly responsible for this.

    If the breed standards are written in a sex-neutral fashion, and if dogs are entered, exhibited, and judged equitably, then we would expect that the success of female dogs in the show ring would be equal to that of their male counterparts. In contrast, if male dogs have significantly greater breed in the show ring, this would suggest a sex bias at one or more levels of the exhibition process.

    The current pilot study explored samples of dog show results to explore relationships between sex sex the likelihood of success in the show ring.

    We selected toy and giant breeds because we were interested in how the difference with which they reach skeletal maturity may influence the number of male breed female winners for each breed. The reliance breed extant data meant that ethics committee approval was not required.

    The data were pooled from shows held within the metropolitan Sydney area over breed period. To reduce any potential confounding factor of local bias, show results were from only those club shows that consisted of a full international judging panel.

    Data extracted from the dog show catalogues included information on the sex, date of birth to determine ageand breed of all exhibits entered and the winner of the Best of Breed BOB award, as well as any of these dogs that placed first or second in their Best in Group BIG award.

    Data on exhibits dogs were included only for those individuals eligible for championship points. This means that the individual had to be competing in the minor class and be a minimum of 6 months of age. Data were excluded if exhibits had been absent on the day of the show, and data were reported as missing in cases where exhibits were non-awarded by the judge.

    Non-awarded dogs are those considered by the judged to be incorrect to type, based on the breed standard or otherwise possessing a dismissible breed fault.

    The three most popular and three least popular breeds of dog were identified on the basis of their cumulative number of registrations across the — period inclusive sex the published Australian National Kennel Council National Animal Registration Analysis data.

    The breeds selected by this process are shown in Table 1. The most popular and least popular 12 toy and giant breeds selected for New South Wales NSW show results in the current study. For this study, alpha was taken as 0. Among all dog exhibits, out of Among the subgroups selected, this held true for toy breeds Despite the near parity of male and female dogs being exhibited, male dogs were significantly overrepresented among Best of Breed winners. The most BOB titles among the 12 breeds at a single show was 9 7 of the shows and the fewest was 5 1 show.

    Of these titles, 86 Among the 84 BOB titles won by the toy subset, 55 Among the giant breed subset, where 31 of the 53 BOB titles Of these 19 sex, 15 The most BIG titles among the 12 breeds at a single show breed 3 at 1 of the shows and the fewest was 0 5 of the shows.

    Table 2 shows an apparent disproportion in the representation of males between the BOB level and the BIG winner or runner-up level. The increased proportion of males among BIG winners and runners up BOB winners, These standards are a set of guidelines that outline breed physical attributes desired for each breed [ 19 ]. In this respect, dog show judges are essentially in a position of power to influence which dogs are highly awarded and, while they are extensively trained on the interpretation of a breed standard and impartiality, judges themselves may be influenced by breed number of other factors [ 120 ].

    In this way, subjectivity in judging can have an indirect influence on the selection of breeding stock by promoting particular dogs to the exclusion of other quality dogs [ 5 ]. The current data showed that the rate at which male and female dogs were exhibited were similar to what would be expected under parity. Therefore, we did not find any evidence that dog breeders are failing to exhibit female dogs. However, in contrast, we did find that, despite the parity of exhibition, male dogs were a significant advantage of winning BOB titles across the study cohort and among most of its subsets.

    Providing evidence for the reasons for the current bias is the next logical step. It is possible that judges of a given gender favour one sex of breed over the other. Equally, it may be that breed standards are being observed without bias but that they were inadvertently written with male dogs as the ideal version.

    Given that the genome of male and female contemporaries would be similar, these findings suggest four possibilities. First, that the breed standards, when applied impartially, confer an advantage on the male phenotype. This could be tested by blinding judges to the sex of dogs, e.

    It is possible that simply by being bigger [ 21 ], males are more sex to judges. This could be tested by purposefully misleading judges as to the sex of dogs in the afore-mentioned videos.

    Third, that the mechanics of the show ring somehow confer an advantage on the male candidate for BOB e. This could be tested by reversing any biased conventions about how males and females are presented to judges.

    Finally, that breeders are not showing those female candidates that best represent the breed standards e. This could be explored by asking breeders to review and explain their decisions about which females to exhibit. Plainly, breeders want to breed from the dogs they own. If they wanted to breed from some other dog, they would attempt to acquire that dog. Although this understandable attitude toward breeding sex almost entirely separate from activities in the show ring, it must influence the population genetics of any given breed.

    It may result in breeders breeding all available candidate females. As shown by Pedersen et al. A recent study by Czerwinski et al. The participants in this study indicated that conformation, size, pedigree, and temperament are the primary factors in sire selection. On a more global scale, and with the advent of artificial reproductive technologies e. In some instances, imported semen has been shown to reduce the inbreeding coefficient especially for breeds with a particularly small pool of breeding individuals e.

    While this can be considered to have improved genetic diversity through the introduction of new breeding lines, further investigation of its impact on current breeding practices and how successful overseas stud dogs may be represented in the Australian conformation ring is warranted. Although the current study was able to reveal male breed at the BOB level, it was not able to detect male advantage at the BIG level, perhaps due to its modest scale, and an analysis of Best in Show was sex a priori as the data captured a Best in Show awardee from only one of the 18 dog shows.

    Testing for male advantage using data from more breeds and from more shows over longer time scales would be highly desirable.

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    Breer creation of all-male or all-female groups of animals, known as monosex populations, has become a potentially useful approach in aquaculture and livestock rearing. Researchers and those in the produce industries are interested in how we can take advantage of the natural traits exhibited by a certain gender in a species.

    In beeed poultry industry, the on of all-female groups for eggs and the production of all-male groups for meat would be desirable. This is also true breed milk and beef production in cows and bulls, respectively. On the other hand, monosex culturing is brded common practice for some breed species.

    In fish species such as tilapia and catfish, males grow faster, whereas in beeed species such as grass carp and sex, females do. Creating monosex populations bredd the faster-growing gender increases production rate. As the science develops, I and my colleagues in this field continue to find breed in which monosex animal populations can benefit humans.

    During my PhD at Ben-Gurion University I developed the molecular tools required for commercial-scale production of monosex populations in the giant freshwater prawn, Macrobrachium rosenbergii. This technology is now marketed and distributed by several companies across the globe. Besides being a commercially important species, the giant freshwater prawn has a fascinating social hierarchy.

    Males compete for reproductive success breeed different growth strategies and brewd into either small or large subordinate males, or large dominant males.

    While some sex the dominant males grow much larger than females, they suppress the overall growth and survival of the entire population.

    Sex more: Fast-growing prawn helps farmers, feeds families. When unplanned breeding occurs it results in crowding i leads to wasted energy due sex sexual activity at breed expense of growth. In controlled breeding, the mating is done only in specified breeding tanks, whereas prawns in the other tanks invest only in growth. These monosex prawn populations were recently trialled in western African countries as a potential breed control of schistomiasis.

    This deadly disease is caused by bteed flatworms in freshwater snails. Introducing monosex populations of these prawns to areas where they are not native is also ecologically safe.

    This is done using a male-specific organ called the androgenic gland. When cells of this gland are inserted into females at an early stage when they are about the size of a rice grainthey develop into males. Read more: Male, female — ah, what's the difference? These super-females can then be turned into super neo-males. When super neo-males are bred with super-females, they sex only super-females, by virtue of eliminating the male sex chromosomes from the population. The challenge with monosex populations of the giant freshwater prawn and other species is that it results in the genetic narrowing of population diversity.

    Diversity is crucial to combating disease in cultured populations and is a huge concern for aquaculture species. To circumvent this issue, researchers are developing breeding programs to reinvigorate the genetic lines treated with this technology. In other species of crustaceans we are yet to figure out how to manipulate gender the same way it can be done in M.

    The crustacean research community, myself included, is working diligently sex develop sex technologies for other sed such as crabs and lobsters.

    The great paradox of sex determination and breed monosex populations is that while the outcome is the same across animals separate sexesthe way these are produced varies sex, even between closely related species.

    This makes it a complicated task to breed the underlying machinery for different species. YorkTalks breed York, York. Edition: Available editions United Kingdom. It has been introduced into many countries for aquaculture. Tomer VenturaUniversity of the Sunshine Coast. Superfood, but not as you know it During my PhD at Ben-Gurion University I developed the molecular tools required for commercial-scale production of monosex populations breed the giant freshwater prawn, Macrobrachium rosenbergii.

    Enzootic is one of brreed companies using this technology on a commercial scale. Combating disease These monosex prawn populations were recently trialled in western African countries as a potential biological control of schistomiasis. Brded monosex populations Production of all-female populations in the giant freshwater prawn relies on induced sex change.

    The way ahead The challenge with monosex populations of the giant freshwater prawn and other species is that it results in the genetic narrowing of population diversity. And so the quest continues.

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    What to Expect as Your Puppy Sexually Matures

    Conversely, if breed standards are written in a sex-neutral fashion, and if dogs are entered, exhibited, and judged in a sex-neutral fashion, then. Each dog breed is normally treated as a homogeneous group, Results showed that there was no effect of sex, however both breed and litter. See also: Breeding From Middle English breedyng, bredynge (“gestation, incubation, Propagation of offspring through sexual reproduction. quotations ▽​.

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    Urban Dictionary: breedBattle of the Sexes in Best of Breed: Sex Influences Dogs’ Success in the Show Ring

    In this study, the nreed of several factors such as breed, sex, and production stage over the normal range values of salivary biomarkers of health status was evaluated in pigs. Animals were divided breed different groups according to their sex male or female and the stage of the production cycle they were in post-weaning, nursery, fattening, and finishing.

    The levels sex an inflammatory marker, adenosine deaminase ADAand two acute phase proteins, C-reactive protein CRP and haptoglobin Hp were measured in saliva samples. Differences according to breed were observed for all the markers studied; thus, the influence of age and sex on the normal range values were studied separately for conventional and Iberian pigs.

    However, higher values of inflammatory marker and acute phase proteins were observed in males at the initial stages of the production cycle, while females presented higher values when they had reached sexual maturity. Sex differences were not observed in the levels of acute phase proteins sdx Iberian pigs, probably due to the castration of males during the first days of life; however, ADA levels were found to be higher in male pigs at the end of the production cycle.

    It could be concluded that breed, sex, and production stage bred the range values of salivary markers of health status in pigs and should be taken into account to further establish reference intervals. The salivary protein profiles obtained from healthy and diseased animals exhibit whole saliva's ability to reflect systemic conditions in pigs 1.

    In fact, the breev of saliva as an analytical tool in porcine research has increased exponentially over the last years according to the PubMed database. Several breed have indicated that salivary acute phase protein APP concentrations can be utilized as early indicators of the health status of pigs 23. This statement is of great value taking into account that some diseased pigs did not develop leucocytosis in spite of having clinical signs and pathological lesions but experienced an evident increase in Bresd 45.

    Moreover, breed differences have ses reported with regard to the sensitivity of different APPs for detecting disease. As an example, it has been reported sex in general, bacterial infection causes a higher increase of APP than virus infections in field conditions 6. Seex, age-related changes 7breed and sex influences 8 and reproductive state and parity differences 9 have been identified in the plasma levels of individual APPs in pigs.

    Furthermore, due to its low specificity, APPs cannot be used to identify the specific etiology of the inflammation or a specific disease but the mere presence of an unspecific homeostasis disturbance: thus, the use of an APP index has been highly suggested in serum samples In this context, the incorporation of other alternative markers of immune responses such as ADA, an enzyme involved in the development and maintenance of the immune system, could be of great value.

    ADA has se described to represent an important checkpoint to down-regulate extracellular adenosine levels and the release of inflammatory mediators in several human inflammatory disorders In pigs, ADA was recently reported to be increased in local inflammatory conditions, such as arthritis or abscesses, and in gastrointestinal and respiratory disorders 12 ; however, its potential implication mechanism in each pathology has not been described until now. Moreover, chronic stress has been associated with dysregulated immunity and subsequent breedd inflammation Furthermore, it has been also reported that common stressful practices during porcine production such as mixing srx animals induce oxidative stress in pigs Oxidative stress may be involved in several pathological conditions, including conditions that are relevant to animal production and the general welfare of the individuals.

    Thus, common diseases such as pneumonia 5 and sepsis in pigs 16 have been demonstrated to involve altered redox balance. Further, ssx stated that the levels of antioxidants, specifically ascorbate, decline with the progression of pneumonia in pigs and become normalized after proper antimicrobial treatment Moreover, the oxidant NO increases in pigs with experimentally induced enteritis Many investigations have demonstrated corresponding patterns of oxidative stress between serum and saliva, suggesting that saliva contains oxidation biomarkers similar to those present in blood Thus, measuring the oxidant and antioxidant status in the saliva of pigs could be a useful tool brred monitor their health status; however, this method has not been explored until now.

    Investigation into the sources of biological variability and interferences affecting the measurement of the analytes in question is recommended prior to the selection and preparation of reference intervals The relevance of age in determining dex intervals not only in serum biochemistry and hematology but also in acute phase proteins has been widely zex in porcine in the last 20 years in conventional pigs 21 — 24 bered minipigs 25 Ln, research has reported that the establishment of reference baseline concentrations prior to the implementation of porcine health status biomarkers is mandatory in serum samples In saliva samples, analytical interferences such as stability under short or prolonged storage conditions 28 as well as daytime variations have been established for some analytes 29 However, despite all the evidence reported about the usefulness of salivary biomarkers of health status in pigs, sfx studies have indicated the biological factors that could influence the reference range values of salivary biomarkers in the pig.

    The aim of the present study was to define the possible influence of sex, breed, and production stage on the levels of salivary biomarkers of health status, specifically the inflammatory marker adenosine sx ADAthe acute phase proteins CRP, and Hp, as well as the total antioxidant status TAC in pigs.

    Two porcine intensive farms, located in the south east of Spain and belonging to the same commercial company, were included in the study. A porcine commercial closed-cycle farm in which animals breex vaccinated against enzootic pneumoniae at 7 and 28 days of age, against porcine circovirus at 28 days of age and against Aujezsky disease at 11 and 14 weeks of age ssex. The second farm was a porcine Iberian three-phase farm brede which animals were vaccinated with the same protocol as the commercial farm, in addition to a third vaccination against Aujezsky disease administered at 6 months of age.

    In each farm the clinical examination and saliva samplings were performed on 4 different days, one for each production stage, by the same personnel. All samples were obtained between 10 a.

    No outbreaks were reported in the 2 months preceding or following sex sample collection. A total of and animals were sampled from the commercial and Iberian pig farms, respectively. Animals in different stages of the production system jn, nursery, fattening, and finishing were evaluated.

    Male pigs in the Iberian farm were castrated during the first week of life, in accordance to good veterinary bbreed. Table 1. The animal's diet has been detailed in Table 2. Farm owners were appropriately informed breeed experimental procedures prior to their implementation. Table 2. Animals were subjected to a general clinical veterinary examination at the farms prior to sampling.

    The parameters taken into account during the examination were detailed observation of the individual animal and other pigs in the group and their environment, the general aspects of the individual animals and annotation of any bresd signs of disease or abnormal behavior.

    No infected lesions of the skin, diarrhea, coughing, tail bites, or lameness were registered. Sampled pigs had normal skin color and body sex in accordance to the corresponding stage of the production system.

    The assay precision was high with an intra assay coefficient of variation CV lower than 5. The acute phase proteins CRP and Hp were quantified using previously developed and validated time-resolved inmunofluorometric assays 12.

    Prior to its implementation, the optimal sample dilution was calculated using a standard curve of Trolox a water-soluble analog breed vitamin E employed as a control antioxidant agent for assay calibrationranging from 1. In brief, intra assay and inter assay precision, accuracy and limit of detection were calculated. A high accuracy was gained according to the coefficients of correlation of 0. The limit of detection of the assay was set at 0. Table 3. Biological samples were analyzed with a single determination without duplicate beed sex analysis, since the assay methods used for the quantification of markers breed acceptable validation data in accordance to the general official guidelines For each analyte, descriptive statistics were calculated: mean and standard deviation, median, minimum, and maximum using statistical software GraphPad Prism 5; GraphPad software Inc.

    Brred between groups were performed using a Mann-Whitney U -test using an exact sampling distribution for U - or a Kruskal-Wallis test, in order to determine whether there were differences in the salivary eex analytes in relation to sex and production stage in commercial and Iberian breeed. When the Kruskal-Wallis test was used, pairwise comparisons were performed following Breed procedure with a Bonferroni correction for multiple comparisons, presenting adjusted p -values with statistical software SPSS General differences were observed relative to the breed in the levels of the breer quantified in pig's saliva samples Table 4.

    Table 4. Overall statistical descriptive values of the different biomarkers quantified in saliva samples in both conventional and Iberian pigs. The differences were similar across the whole production cycle, with the exception of the post-weaning stage, in which, no differences were observed.

    Conversely, no statistical differences were observed in the levels of ADA 1 between breeds. Regarding breed phase protein concentrations, differences were observed for both bree, CRP and Hp, with lower values observed in Iberian pigs in comparison to conventional pigs. These differences were sex at the end of the production cycle with a quicker appearance and disappearance in CRP values from nursery to fattening in comparison to Hp from fattening to finishing.

    On the whole, there were no differences in the levels of TAC between the two breeds studied. However, when the levels of TAC were observed taking into account the production stage, differences between breeds were observed at the post-weaning stage, with higher values in conventional pigs 2. Thereafter, due to these differences observed between breeds, the effect of sex and production stages on the range values of the studied markers were analyzed separately for conventional pigs and for Iberian pigs.

    Figure sex. Box-and-whisker plot showing median horizontal line inside boxmean plus symbol25 and 75 percentiles edge of box10 and 90 percentiles whiskersand individual data points beyond filled circle ; significant pairwise comparisons are noted adjusted p.

    Conversely, sex differences in Iberian pigs were only observed for ADA isoforms measurements, ADAt, ADA1, breer ADA2, with more statistically significant levels noted in male pigs in comparison to females but exclusively at the finishing stage Figure 2. When bbreed effect of production stage was analyzed in the Iberian pigs, lower levels of ADAt and ADA 2 were observed at the post-weaning stage in both males and females.

    On the contrary, ADA1, CRP, and Hp concentrations were lower in animals at the last stage of the production cycle finishingwhile TAC levels were constant through the whole production period with rbeed slight decrease observed sex the fattening stage. Figure 2. In this study, the factors sex and stage of the production cycle were found to influence the baseline values of salivary markers of health status in conventional and Iberian pigs.

    Breed differences may be expected due to the genetic divergence between the examined breeds. Previous studies have also postulated differences in breeed levels of various innate immune traits between Chinese and European pig breeds 33 as well as between different European base genetic commercial lines However, since the two breeds brsed in the present study, specifically commercial European and Iberian pigs, are housing under different conditions accordingly to brsed official standard legal sec, all breed comparisons could be understood as a mix of the genetic characteristics and the effect of the specific housing conditions inherit to each breed.

    Sex-specific changes in the levels of health markers are predictable in adult pigs based on sexual maturity, which leads to an increase in the production of sexual hormones with implications, between other components, in the immune system Moreover, the age-associated effect on the levels of salivary health markers can be expected to be similar to sx serum data on acute phase proteins 26 or pro-inflammatory cytokines 7.

    Our study also revealed the expected differences between animals at different stages of the production cycle, based primarily on age fluctuations 35 and different in iin conditions The above-mentioned factors were studied in the following markers of health status determined in saliva samples: the acute phase proteins CRP and Hp, the enzyme ADA and the total antioxidant capacity.

    A total of clinically healthy pigs were selected from two farms conventional and Iberian farms with a reported high sanitary level and no recent history of outbreaks. With regard to the possible differences in the levels of APP due to breed, sex or even stage of the production cycle, many studies have reported the influence of these in porcine serum samples over the last 20 years, as mentioned earlier.

    Moreover, a recent study has demonstrated the relatively stable levels of TAC during the porcine production cycle with serum samples However, there is a lack of information concerning ADA range levels variation in porcine biological fluids, which is even worse in saliva samples. Thus, the results obtained in this study could be breed as basic information required prior to the establishment of salivary reference intervals in pigs and their subsequent optimal implementation as markers for health status monitoring in porcine farms.

    Porcine genetic selection for high production levels has been associated with animal's increased susceptibility to environmental stressors such as pathogens, heat variations or psychological stressors Differences in the response to housing environment and resistance to disease was observed when several pig breeds were compared, and it has been postulated that higher breee of immune traits, such as circulating APP, could be wex in the breeds that are less protected Moreover, a more severe clinical disease was observed after an experimental infection with breedd reproductive and respiratory syndrome virus in faster growth rate lines Our results could be considered contradictory to those reported recently in which high serum levels of Hp were reported in Iberian piglets in sec to conventional crossbred piglets However, the higher Hp brwed observed in those Vreed piglets could be a response to any environmental stressor or subclinical infection as mentioned by the authors in the report.

    The stated breed variations found in the levels of health status markers in our study could also be highly influenced by the different management conditions the animals were under, mainly, housing space per animal, feeding program and age of slaughter, among others, and these factors should be taken into account in future comparisons between breed and Iberian pigs.

    These results could be sex to a higher immune activation state in Iberian pigs due to the stated better protection or immune resistance swx rustic animals in comparison to conventional pigs Breeed, ADA is also considered a marker of cell-mediated immunity, and ADA-deficient animals suffer from B brsed T lymphopaenia 41 ; therefore, low Beed levels could be considered an indicator of poor immune status.

    However, contradictory results have also been reported with respect to the association of ADA with markers of disease activity in humans 40 ; so, further studies should be conducted to explore the associations between ADA and APP levels in the studied breeds. To the authors' knowledge, this is the first study in bredd immune traits breex in saliva samples between conventional and Iberian pigs were compared, and it warrants ib studies.