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PubMed2004

Study on polymorphisms of microsatellites DNA of six Chinese indigenous sheep breeds.

The polymorphisms of 17 microsatellites loci of six indigenous sheep breeds, including Mongolian sheep, Ujumuqin sheep, Kazakstan sheep, Aletai sheep and Tibetan sheep, were studied using polypropylene gel electrophoresis in order to investigate their genetic diversity,origin, differentiation and relationships. The results indicated that there was a significant difference in genetic diversity between different loci (P < 0.01). There was no significant difference in PIC, Fis and observed heterozygosity (Obs. Het) among populations (P > 0.05), but a significant difference in gene diversity and expected heterozygosity (Exp. Het) (P < 0.05). Chinese indigenous sheep breeds had similar genetic diversity as those from Europe,but with higher inbreeding coefficient. It could be inferred from the cluster of individuals and populations that Chinese indigenous sheep breeds might originate from two ancestors. The cluster of populations showed that Mongolian sheep and Ujumuqin sheep had close relationship and did not differentiate obviously. Mongolian sheep and Tibetan sheep had far relationship and differentiated significantly. Aletai sheep differentiated from Kazakstan sheep but not significantly. Tan sheep,Aletai sheep and Tibetan sheep also had close relationships. The Fst of Chinese indigenous sheep breeds was close to some Spanish sheep breeds,but much smaller than that of other European sheep breeds. More loci and samples should be studied in the future in order to obtain more accurate results.

Animals↗
PubMed2004

Role of some factors on the breeding of JE vector Culex vishnui group.

Vector of JE, Culex vishnui group, prefer to breed in rice field. During the present study, roles of some factors like irrigation, manuring, pesticide application, rainfall, temperature and pH of the breeding water, depth of breeding water and height of paddy plants on breeding of Culex vishnui group larvae have been studied. It is evident from the study that besides striking role of the factors like manuring and pesticide application, other factors have also some role on the breeding of JE vectors at their breeding sites.

Agriculture↗
PubMed1990

[Remarkable domestic animal breeds in California].

In the United States, especially in California, there is a surprising variety of farm animal breeds. This multitude of different forms is a result of the history of this State. Some breeds came from other countries, others were developed from feral animals and yet others were created in this state by crossing and selective breeding. Several of these breeds soon attained a high level of performance and they were exported to many other countries. Others remained primitive landraces with special adaptation or had unusual morphological characteristics. There are some breeds that influenced the history of North America considerably. This is only one reason why these breeds should be sustained as a cultural heritage.

Animals↗
PubMed1989

[The native domestic animal breeds of Japan].

During the last decades some domestic animal breeds have spread to all parts of the world. In general, consideration is given to these breeds only; on the other hand, autochthonous breeds of various countries are hardly known. These, however, can be valuable gene-reserves, and moreover, they represent a significant cultural value. In Japan there are several domestic animal breeds which are almost unknown in Central Europe. They are presented verbally and by means of illustration, and their breeding history is dealt with as well. The purpose of this study is to point out the importance of these breeds within the country and to make clear the extent of the danger of their extinction.

Animals↗
PubMed1986

[Endangered farm animal breeds in German-speaking countries. II. Cattle].

The development of farm animals since the beginning of domestication is described. Modern breeds have existed since the end of the 18th century. Different efficiency with regard to what were topical breeding aims as well as manipulations by the government led to a decrease in the variety of breeds. The reasons of preserving endangered breeds are both genetic and cultural. There are some examples of breeds that once had little attention payed to and which now have obtained economic importance again. In recent years several institutions in West Germany have tried by financial advancement and other measures for a variety of breeds to avoid further curtailment of them.

Animal Husbandry↗
PubMed1977

Behavioral research in breeding colonies of Old World monkeys.

The existence of an active behavioral research program using animals in primate breeding colonies was considered to be not only a compatable multiple use of animals, but a way of materially improving the management and efficiency of the breeding colonies. In colonies of monkeys specifically established for behavioral research programs directed at the examination of social relationships, incidental breeding resulted in levels of reproductive success equivalent to or greater than that normally experienced in colonies devoted entirely to breeding. Behavioral research revealed patterns of seasonality, fostering, kidnapping, and infant care which would otherwise have escaped notice and which would significantly influence culling and management choices in a breeding colony. Many young males and certain low ranking adult males actively contributed to reproduction. Females born and reared in the colonies were the most productive, exceeding wild born or other introduced females in reproductive efficiency. Specific recommendations for establishing, expanding and culling of nonhuman primate breeding colonies were derived from the behavioral research.

Animals↗
PubMed1978

Effect of interval between booster vaccination and time of breeding on protection against campylobacteriosis (vibriosis) in cattle.

Thirteen heifers (group A) given a booster vaccination with Campylobacter fetus 4 1/2 months before breeding to bulls infected with the homologous strain had a pregnancy rate of 54%, compared with a pregnancy rate of 92% for 12 heifers (group B) given a booster vaccination 10 days before the 63-day breeding period began. None of 7 nonvaccinated heifers became pregnant, and all remained infected for at least 136 days. All three groups of heifers were bred by the same infected bulls. Nine of the heifers in group A, but none of the heifers in group B, became infected during the first estrus. Blood serum agglutination titers peaked 2 weeks after the first vaccination but decreased to prevaccination titers 6 weeks later. Titers more than double those produced by one vaccination peaked between 2 and 3 weeks after booster vaccination but in most heifers had decreased to low titers 7 weeks later. When the breeding period began, the median antibody titer was 640 for heifers in group A and 10, 240 for heifers in group B. Indications of an anamnestic response due to natural challenge were not found in any of the 9 infected heifers in group A when serum titers were determined 27 and 34 days after breeding began. Therefore, it appears that in many heifers and cows, only the antibodies produced by booster vaccination will be available to provide protection. Inasmuch as vaccinal antibody titers decrease rapidly, it was concluded that booster vaccinations should be given approximately 10 days before breeding so that titers will be high during the breeding period.

Animals↗
PubMed1981

Breeding of Macaca fascicularis for poliovaccine production.

In our Institute Cynomolgus monkeys (M. fascicularis) are mainly used for production and control of poliovaccine. In 1974 a small individual breeding colony was started. Last year the colony was enlarged with 10 harem groups. Based on colony reproduction data, group breeding seems more successful than individual breeding. Owing to developments in the production of poliovaccine, a state of total self supply is within reach. However attention must be paid to factors reducing breeding results, comprising aggressive interactions and disturbed mother-care. Finally replacement of breeding stock might require rearing conditions which are not compatible with those necessary for the establishment of a Foamy virus and Herpes-B virus breeding colony.

Animals↗
PubMed1994

[Breeding control and immobilizing effects of wood microingredients on house dust mites].

The possible effects of essential oils as wood microingredients on house dust mites (Tyrophagus putrescentiae, Dermatophagoides farinae and Dermatophagoides pteronyssinus) were investigated. 1. Whether small pieces of 5 types of wood had any control effect on mite breeding was studied. Mite breeding using only normal feed was compared with breeding using feed mixed with small pieces of wood. In addition, mite breeding using feed mixed with small pieces of wood with no essential oil was studied. 2. Effects of 6 different wood essential oils in immobilizing mites were studied with regard to respired and contact toxicities. 3. The immobilizing effects of 10 ingredients in Hinoki oil were also specifically studied with regard to contact toxicity. The results of the 3 experiments were as follows: 1) It was confirmed that the small pieces of Hinoki, cedar, pine and Lauan had control effects on mite breeding. However, the small pieces of spruce did not demonstrate an effect. Woods which had no essential oils had reduced or no breeding control effects. 2) It was confirmed that the 6 different wood essential oils had mite immobilizing effects associated with respired and contact toxicities. Rosewood oil, White Pine oil and Taiwan Hinoki oil had strong immobilizing effects. Hinoki oil, however, had only a weak effect. 3) Among the 10 ingredients of Hinoki oil, specifically Linalool, Geranyl acetate and alpha-Terpineol had strong mite immobilizing effects.

Animals↗
PubMed1993

An attempt to correlate cattle breed origins and diseases associated with or transmitted by the tick Amblyomma variegatum in the French West Indies.

By using biological data and historical research, we have tried to explain the difference between resistance and susceptibility to the diseases transmitted (cowdriosis) or associated (dermatophilosis) with the tick Amblyomma variegatum, in two cattle breeds of the French West Indies: the Creole crossbred cattle of Guadeloupe and the Brahman zebu cattle of Martinique. Have been studied the polymorphisms of 5 independent genetic systems (erythrocytic haemoglobin, serum albumin and transferrin, the class I region of the BoLA complex and the gamma S crystallin gene) in different breeds comprising Bos taurus cattle of Europe and Africa, Bos indicus of West and East Africa, as well as the Brahman of Martinique and the Creole crossbred of Guadeloupe. By comparing the different allele frequencies of these 5 non related polymorphic loci and by using the two different mathematical matrices of NEI and of CAVALLI-SFORZA, have been established the genetic distances between these breeds. It appears clearly that the Creole cattle of Guadeloupe are in an intermediate position between the Bos taurus N'Dama breed of West Africa and two Bos indicus zebu breeds, namely the West African Sudan zebu and the Brahman. Thanks to studies of different archieves in the Caribbean and in Europe, historical evidence have been accumulated on the geographical origins and on the chronology of the establishment of Creole and Brahman cattle in the French West Indies. The high resistance of the Creole cattle of Guadeloupe to diseases associated with or transmitted by the "Senegalese" tick Amblyomma variegatum seems to be due to the inheritance of a pool of genes from West African cattle and more particularly from the N'Dama breed.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1999

Urolithiasis in dogs V: regional comparisons of breed, age, sex, anatomic location, and mineral type of calculus.

OBJECTIVE: To determine extent and nature of regional differences in distribution of canine urinary calculi. SAMPLE POPULATION: 13,552 calculus specimens: 7,056 (52.1%) from females, 6,492 (47.9%) from males, and 4 from dogs of unrecorded sex. Procedure Records were used to compile information from all specimens submitted between July 1981 and December 1995. Results from mixed-breed and various breeds of stone-forming dogs were analyzed. Interrelations of breed, sex, and age of dogs, and anatomic location and mineral composition of specimens were analyzed and compared for 6 US geographic regions. RESULTS: Struvite-, apatite-, and urate-containing calculi were reported significantly most often from female dogs of the Mountain/Pacific region. Oxalate-, silica-, and brushite-containing calculi were reported significantly most often from male dogs in the New England/mid-Atlantic (NEMA) region. Cystine-containing calculi were reported most frequently from the NEMA and South Central (SC) regions. Dogs from the NEMA region were oldest in average age at diagnosis. Significant regional differences in distribution were found for several breeds. Sex distribution of renal calculi in 11 breeds of dogs (Lhasa Apso, Yorkshire Terrier, Shih Tzu, Basset Hound, Pug, Mastiff, Bichon Frise, Doberman Pinscher, Dalmatian, English Bulldog, and Pekingese) reported to be at high risk of renal lithiasis differed among the 6 geographic regions. Renal and ureteral calculi were reported significantly most often from dogs in the South Atlantic region, and bladder and urethral calculi were reported most often from dogs in the SC region. CONCLUSIONS: Wide regional differences exist in distribution of stone-forming dogs by sex, average age at diagnosis, breed, and minerals contained within and anatomic location of calculi.

Age Factors↗
PubMed1999

Morphological, morphometric, and functional differences in the vestibular organ of different breeds of the rat (Rattus norvegicus).

In the laboratory rat, differences in shape, dimension and function of the cochlea have been reported for various breeds. In contrast, no comparable investigations to date have been undertaken for the vestibular organ in different breeds of the rat. Vestibular organs of two breeds of rat (Wistar, Sprague-Dawley) were analyzed morphologically and morphometrically by means of microdissection techniques in order to determine the mechanical sensitivity of the cupula according to Oman et al; (Acta Otolaryngol., 1987;103:1-13, 1987). Differences in shape of the lateral semicircular duct exist between the two breeds and the cupular mechanical sensitivity is significantly higher in Wistar than in Sprague-Dawley rats. With respect to the other semicircular ducts, no differences in shape were found between the two strains. The cupular mechanical sensitivity of the anterior semicircular duct, however, is higher in Wistar than in Sprague-Dawley rats. The breeds also differ in the shape of their utriculus; obviously a correlation exists between the latter and the cupular mechanical sensitivity of the semicircular ducts. There are differences in the vestibular organs between the two breeds of the laboratory rat investigated. The cupular mechanical sensitivity of the semicircular duct does not seem to be correlated to body mass. The size and morphology of the utriculus influence the mechanical sensitivity of a single duct, but differences only become significant if other parameters also differ.

Animals↗
PubMed1997

Group size and aggression: 'recruitment incentives' in a cooperatively breeding primate

In many cooperatively breeding birds and mammals, group size is positively correlated with reproductive success. In marmoset and tamarin monkeys, species that display cooperative breeding, the presence of helpers appears to be critical for offspring survival, and breeders might be expected to display social strategies that would regulate group size. This study investigated the association between group size and aggression towards strangers in Wied's black tufted-ear marmosets, Callithrix kuhlifrom small groups (with no helpers present) and large groups (with helpers present). Residents were exposed to multiple presentations of male and female strangers. Breeding females from large groups spent more time in close proximity to strangers, showed higher levels of agonistic displays and engaged in higher levels of aggressive behaviour towards intruders than did breeding females from small groups. Breeding male behaviour did not dramatically differ as a function of group size. After the removal of the intruder, female breeders from large groups showed higher levels of scent-marking relative to baseline observations, and time spent in close proximity to the partner increased after exposure to female intruders in large, but not small, groups. The results reveal that breeders from small groups are tolerant of strangers, which may facilitate the recruitment of additional group members, whereas breeders from large groups, particularly females, are intolerant of strangers, which may inhibit immigration. These findings have implications for understanding mechanisms that regulate immigration in cooperatively breeding animals, and suggest of how breeders from small groups might reconcile the serious limitation of having few or no helpers.

Journal Article↗
PubMed2000

Mate fidelity and breeding site tenacity in a monogamous sandpiper, the black turnstone.

We examined the relationship between mate fidelity and breeding site tenacity during a 5-year study of the black turnstone, Arenaria melanocephala, a socially monogamous sandpiper breeding in subArctic Alaska. We tested the predictions of several hypotheses regarding the incidence of divorce and the benefits of fidelity to mate and breeding site. Interannual return rates to the breeding grounds (88% for males, 79% for females) were among the highest yet recorded for any scolopacid sandpiper, and 88% of returning birds nested on their previous year's territory. The annual divorce rate was only 11%, and mate fidelity was significantly linked to fidelity to territory but independent of sex and year. Males arrived in spring significantly earlier than their mates and interannual fidelity was influenced by the relative timing of arrival of pair members. Reunited pairs had significantly higher fledging success than new pairs formed after death or divorce. The incidence of divorce was unrelated to reproductive success the previous year, although birds nested significantly further away after failure than after a successful nesting attempt. Sightings of marked individuals suggested that members of pairs do not winter together, and breeding site tenacity provides a mechanism through which pair members can reunite. We reject the 'incompatibility' hypothesis for divorce in turnstones, and our data contradict predictions of the 'better option' hypothesis. Alternatively, we propose the 'bet-hedging' hypothesis to explain the occurrence of divorce, which transpires when an individual pairs with a new mate to avoid the cost of waiting for a previous mate to return. Such costs can include remaining unmated, if the former mate has died, or experiencing lower reproductive success because of delayed breeding. Copyright 2000 The Association for the Study of Animal Behaviour.

Journal Article↗
PubMed2001

Reproductive endocrinology of a free-living, opportunistically breeding passerine (white-winged crossbill, Loxia leucoptera).

The aim of the study was to investigate, in a free-living opportunistic breeder, the White-winged Crossbill (Loxia leucoptera), the degree to which annual changes in photoperiod and differences in the timing of breeding in different years correlate with the secretion of reproductive hormones. Seasonal changes in concentrations of luteinizing hormone (LH) and prolactin were compared in White-winged Crossbills in interior Alaska (64 degrees 50'N, 147 degrees 50'W) in plasma samples taken in May-December 1994 and July 1998-August 1999. The birds were in breeding condition in May-July 1994 and in February-April 1999. Additional observations were made on plasma testosterone (T) in males in 1998/1999. In 1998, in adult males, plasma LH and T were low in September-October (LH: <0.4 ng/ml; T: undetectable) and increased significantly in November (LH: 3.65 +/- 2.20 ng/ml) and December (T: 0.69 +/- 0.88 ng/ml). Thereafter, plasma T increased to 2.35 +/- 2.03 ng/ml in March/April and returned to basal levels by June/July. In 1998/1999, in females, plasma LH did not change seasonally. In males in 1994, plasma LH was higher in June (2.15 +/- 1.22 ng/ml) and July (2.86 +/- 0.69 ng/ml) than in the same period in 1999 (June: 1.20 +/- 1.82 ng/ml; July: 1.37 +/- 1.03 ng/ml), which is consistent with the later breeding season in 1994. In 1994 and 1998/1999 in both sexes, concentrations of plasma prolactin were elevated when day lengths exceeded about 12 h, being high during late spring to early fall (males: 40-130 ng/ml; females: 40-140 ng/ml) and low during winter (<15 ng/ml in both sexes). In 1994 and 1998, molt occurred during the fall, at a time when breeding did not occur, although conifer seeds were sufficiently abundant to support a large bird population. These data are consistent with the view that White-winged Crossbills have the potential to breed at all times of the year except when molting in the fall. It is likely that a photoinduced increase in prolactin secretion is a factor that induces molt. Crossbills may not breed when they are molting because of increased metabolic demands for feather formation and for the maintenance of basal metabolism at a time of year when ambient temperatures fall well below 0 degrees. Alternatively or in addition, the birds may become reproductively photorefractory.

Adipose Tissue↗
PubMed1995

Hormonal correlates of breeding status, nest construction, and parental care in multiple-brooded northern mockingbirds, Mimus polyglottos.

Blood samples were taken from free-living male and female mockingbirds to determine correlations between plasma steroids and breeding behavior. Plasma levels of testosterone (T), estradiol (E2), progesterone (P), and corticosterone (B) were assessed during pre-breeding courtship, while males built nests, while females incubated, while parents fed young, and while males built new nests as pairs continued to care for dependent fledglings. Samples were also taken from unmated males holding spring territories. In males, T and P fluctuated with breeding phase, and in all groups, male T levels exceeded basal values measured in autumn. But, when mated males built nests in the absence of young, T levels were higher than in all other conditions, though only for early broods. In females too, T and P levels changed with breeding phase; T levels rose during courtship and while males built first nests and were intermediate during nest construction for later broods. Male and female P levels rose during courtship and when males built nests with young present. While feeding young in the nest, males showed significantly higher corticosterone levels than females, though in females, both P and B levels increased during incubation for replacement broods. These findings strengthen an earlier finding that T may activate male nest construction, and they suggest that breeding behavior may be related to T in females as well. Progesterone data raise the possibility that P too, may be linked to breeding behavior in male and female mockingbirds. Sex differences in corticosterone levels during the nestling period may reveal subtle costs associated with male mockingbirds' highly aggressive defense against predators.

Animals↗
PubMed1996

Comparison of resistance in three breeds of cattle against African ixodid ticks.

Tick resistance in three breeds of cattle, two indigenous breeds (Arssi and Boran) and one Boran x Friesian cross-bread, were compared following natural tick infestations at Abernossa ranch in Ethiopia. The local Arssi breed was found to have the highest tick resistance, followed by the Boran breed, whereas the Boran x Friesian was the least resistant. Over a period of 12 months, from October 1991 to September 1992, a total of 32,897 ticks composed of four genera were collected from the animals. The four most abundant tick species were Amblyomma variegatum (61.7%), Boophilus decoloratus (16%); Rhipicephalus evertsi evertsi (16.3%) and Hyalomma marginatum rufipes (3.7%). Furthermore, 63.5% of all ticks were collected from cross-breed cattle, and 26.2% from the Boran, whereas the local Arssi breed carried only 10.3%. The results indicated that cattle resistant to one species of tick were also resistant to other tick species.

Africa↗
PubMed1990

Photoperiodic requirements for timing onset and duration of the breeding season of the ewe: synchronization of an endogenous rhythm of reproduction.

A study was conducted to test the hypothesis that different portions of the annual photoperiodic cycle play different roles in timing the breeding season of the ewe, Ovis aries, an animal in which an endogenous rhythm generates the seasonal reproductive transitions. Adult female sheep were pinealectomized to disrupt transduction of photoperiodic cues at 4 times of the year (summer and winter solstices, vernal and autumnal equinoxes), and the effects on seasonal reproductive neuroendocrine activity were evaluated. Time of pinealectomy greatly influenced the subsequent seasonal reproductive cycle such that the following inferences are possible. Lengthening days between the winter and summer solstices synchronize reproductive onset to the appropriate time of year. The relatively long days around the summer solstice act to suppress reproductive activity and forestall the start of the breeding season until late summer/early autumn. The shortening days between the summer solstice and autumnal equinox maintain a normal intensity and duration of reproductive neuroendocrine induction during the impending breeding season. However, the shortening days between the autumnal equinox and winter solstice (i.e., after breeding season onset) do not appear to play a critical role in maintaining the breeding season of that year, but may provide important cues for timing the breeding season of the following year.

Animals↗