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1.
The comparative hoarding behaviour of four rodent species,Saccostomus campeslris, Desmodillus auricula-is. Tatera brantsii and T. leucogaaer was studied under semi-natural conditions after prior determination of the seed preferences of each species.

The results are consistent with all available ecological data. Desmodillus and Saccostomus are true larder-hoarders, although Desmodillus also scatter-hoards on occasion. The Tatera spp. did not hoard, but frequently covered seeds, a possible primitive form of scatter-hoarding.  相似文献   

2.
The distribution of the South African shelduck Tadorna cana was mapped and related to temperature and rainfall. A multiple regression analysis based on quantified spatial abundance (the number of sixteenth degree squares recorded with shelduck in a degree square), mean annual rainfall, mean annual temperature and mean temperature of the coldest (July) and hottest (January) months indicated a significant (P < 0,001) negative linear relation between shelduck distribution and temperature, but no significant (P > 0,05) relation with rainfall. Mean annual rainfall in excess of 600 mm is however suggested to bring about unfavourable habitat within temperate southern Africa. The hypotheses formulated on the environmental relations of shelduck distribution are compared with habitat preference, breeding season, nest sites and feeding behaviour.  相似文献   

3.
《African Zoology》2013,48(1):128-137
The breeding dynamics of three species of rodents, Mastomys natalensis, Aethomys chrysophilus and Gerbilliscus vicina were investigated in a seasonal environment (wet versus dry) in Berega in the eastern parts of central Tanzania. Berega has a distinct unimodal rainfall pattern, with most rainfall from November to April/May. We hypothesized that breeding of rodents in central Tanzania would be confined to the wet season, when unlimited resources would be available for reproduction. We provide evidence of breeding discontinuity in the three species, showing that breeding was seasonally restricted to the wet season and early in the dry season. The observed discontinuity could largely be ascribed to variation in primary productivity between the wet and dry seasons. Reproductively active females were found in the population as early as November, a month into the rainy season, but when early rains occurred, some individuals were already breeding in October. Breeding was more intensive in the latter part of the wet season (March–May) and completely ceased during the dry season. For M. natalensis, survival was highest in the wet period and low in the dry season. The study provides knowledge on the breeding dynamics of rodents in central Tanzania, which can help farmers to take proactive rodent management decisions to prevent high rodent densities and reduce crop damage in the fields. Application of control measures by the community early in the season when populations of reproductive females is lowest will be most rewarding.  相似文献   

4.
As wild population threats for the endangered false gharial (Tomistoma schlegelii) persist, conservation breeding programs, including developing semen collection techniques for subsequent artificial insemination, are becoming important species conservation measures. Developing reproductive biology understanding of a species is important to developing best practices and hopefully maximizing reproductive successes. However, information on crocodylians functional copulatory anatomy in general is lacking. To that end, zoological facilities and conservation centres have the exceptional opportunity to contribute new understandings that may not otherwise be attainable regarding crocodylian reproductive anatomy, particularly during routine physical examinations or post-mortem necropsies. Therefore, to better understand T. schlegelii reproductive biology, to contribute knowledge in support of zoo breeding conservation efforts and to contribute to what is known overall about crocodylian reproduction, we investigated phallic anatomy of adult male Tomistoma from two zoological populations, the St. Louis Zoo, USA and Sungai Dusun Wildlife Reserve, Peninsular Malaysia. Here, we present the gross anatomical features and histological analysis of underlying tissue-level details in pursuit of a better understanding of copulatory function and associated gamete transfer mechanisms. While much of the overall Tomistoma phallic morphology and inferred function corresponds to that of other crocodylian species and speaks to conserved aspects of functional anatomy across taxa, species-specific aspects of glans and glans tip morphology are also identified. These novelties are discussed in a general function and overall broader evolutionary contexts.  相似文献   

5.
The reproductive activity of the redbilled oxpecker Buphagus erythrorhynchus is governed primarily by the effects of rainfall and the onset of the laying cycle is dependent on the time of year at which the rain occurs. At the onset of the rainy season in August or early September the biomass of the Ixodldae increases on the mammalian symbionts and is made use of for feather synthesis during moult. During October with a significant increase in the biomass of Tabanidae it is possible to accumulate a large enough protein reserve to initiate breeding.  相似文献   

6.
The primary objective of most horse breeding operations was to maximize reproductive efficiency and minimize the cost of producing live foals. Here, we compared individual horses from the Thoroughbred population (n = 17), known as a horse breed with poor reproductive performance, with other six horse populations (n = 28), to detect genomic signatures of positive selection underlying of reproductive traits. A number of protein-coding genes with significant (p-value <.01) higher FST values (616 genes) and a lower value for nucleotide diversity (π) (310 genes) were identified. The results of our study revealed some candidate genes such as IGFBP2, IGFBP5, GDF9, BRINP3 and GRID1 are possibly associated with functions influencing reproductive traits. These genes may have been under selection due to their essential roles in reproduction performance in horses. The candidate selected genes identified in this work should be of great interest for future research into genetic architecture of traits relevant to horse breeding programmes.  相似文献   

7.
Field studies (Lake Kariba shoreline and Salisbury) and experiments with a captive colony of 12 species of Rhodesian rodents were undertaken for a period of three years. Comparative behavioural data are presented here with special reference to den and nest behaviour, group and territorial behaviour, reproductive and juvenile behaviour, and activity pattern. No species was found to be truly gregarious except Dendromus mesomelas, but Praomys (Mastomys) natalensis, Lemniscomys griselda, Tatera leucogaster, and Aethomys chrysophilus were found to tolerate crowded conditions in captivity. Nipple dragging of young was found in both species of Aethomys and in Acomys, with the remainder observed to utilise mouth carrying behaviour. It was noted that especially in Rhabdomys and Praomys (Mastomysj, and also in Lemniscomys, young have a strong tendency to scatter in all directions from a disturbed nest, even before their eyes open. The significance of nipple dragging, scattering and crowding behaviour and correlation to survival and tendency to irrupt are discussed. All species were found to be nocturnal (usually with irregular sub cycles of activity) except Rhabdomys (largely diurnal), Lemniscomys (diurnal/crepuscular) and Otomys (nocturnal/crepuscular).  相似文献   

8.
One hundred and nine breeding bulls were examined during the period November 1992 to June 1993 on farms in south west Scotland for evidence of infectious diseases associated with breeding. Preputial washings were collected to screen for Campylobacter fetus venerialis, together with serial blood samples to assess their seroprevalence to Bovine Virus Diarrhoca virus (BVDv), Bovine Herpes Virus-1 (BHV-1), Leptospira hardjo and Bovine Herpes Virus-4 (BHV-4). The possible impact of natural mating on the epidemiology of these diseases is described. Evidence of infections with Campylobacter fetus and BVH-4 were not found in this sample. The overall seroprevalence to BVDv was 78%, for BHV-1 49%, and L. bardjo 27% at titres of ≥ 1/400. This study shows that bulls may be responsible for the introduction and dissemination of these diseases when moved from farm to farm as part of normal cattle breeding in this area. Young unproven bulls may be particularly susceptible to endemic diseases associated with lowered reproductive performance.  相似文献   

9.
CASE HISTORY: An adult female Duvaucel's gecko (Hoplodactylus duvaucelii) from a threatened species breeding programme presented due to a prolonged gestation period and distended abdomen.

CLINICAL AND PATHOLOGICAL FINDINGS: The gecko was in lean body condition with an irregularly shaped, firm mass in the coelomic cavity. Radiographically there was a diffuse radio-opacity within the coelomic cavity with cranial displacement of the right lung field. Ultrasonography revealed a round homogenous abdominal mass of medium echogenicity with an echogenic capsule. Haematology showed a leucocytosis with a moderate left shift in heterophils and toxic changes. Bilateral ovariectomy was performed to remove two ovarian granulomas and Salmonella enterica subspecies houtenae (IV) was cultured from the ovarian tissue. The gecko recovered well from the surgery, regained weight and remained in good health 3 years following the surgery.

DIAGNOSIS: Pre-ovulatory stasis and ovarian granulomas associated with infection with Salmonella enterica subsp. houtenae.

CLINICAL RELEVANCE: The surgery described in this case resulted in recovery of the gecko, which despite its loss of reproductive capability is of value as an education animal. This is the first report of pre-ovulatory stasis and ovarian granulomas associated with infection with Salmonella enterica in a Duvaucel's gecko and is also the first reported case of pre-ovulatory stasis in a viviparous lizard species. The case adds to knowledge regarding potential reproductive pathology in lizards, which is particularly important information for managers of captive lizard breeding programmes.  相似文献   

10.
《African Zoology》2013,48(1):148-152
The Damaraland mole-rat (Fukomys damarensis) is a social, subterranean rodent that occurs in the red Kalahari sands. This species exhibits extreme reproductive skew with a single breeding female whereas reproduction in subordinate group members is completely blocked. Rainfall, as it greatly facilitates burrowing, provides the opportunity for individuals to disperse from their natal colony and hence, to overcome reproductive suppression. However, because rainfall is scarce, optimal conditions for burrow system construction are restricted to very short periods of the year. In order to observe the construction of a new burrow system of dispersing individuals, I released a small group (two females, one male) following heavy rains, and monitored their burrowing activity in the form of mound production during the following weeks. Recapture revealed that a new male had joined the group. Over a period of one month the four individuals extruded 127 mole hills and constructed a tunnel system with a total length of approximately 100 metres. Mound production ceased after 30 days due to the lack of subsequent rain. The study provides an example of dispersal in Damaraland mole-rats and gives new insights into the method of burrow system construction of this species. It further highlights the high costs associated with dispersal.  相似文献   

11.
An old quarry, 2,5 hain size near Livingstone in southern Zambia was kill-and live-trapped between September 1974 and December 1976 to determine ecological relations among. rodent species inhabiting it. Seven species were found to comprise the old quarry rodent community. Praomys natalensis was by far the most common although Saccostomus campestris and Lemniscomys griselda were also abundant. Four species (Tatera leucogaster, Steatomys pratensis, Mus minutoides and Aethomys chrysophilus were rare. Food and micro-habitat preferences of S. campestris and P. natalensis appeared similar. Seasonal fluctuations characterized the P. natalensis population while L. griselda was absent from the site during the latter part of the rainy season and early in the dry season. Pre-weaning survival of P. natalensis was very low, particularly early in the breeding season. The survival of the trappable population was good but declined following a burn at the study site. P. natalensis recruited into the population from May-July, lost between 20 and 35% of their body mass during the August-October period. Body mass increased as rodents attained sexual maturity early in the rainy season.  相似文献   

12.
In recent years, intensive attention has been put on improving reproductive performance of pigs. Several experiments aimed to identify markers associated with prolificacy, but this issue still remains open. In our study, we investigated associations between polymorphisms in IGF2, GNAS and MC4R genes with reproductive traits of Polish Landrace and Large White pigs. We did not find any significant associations for g. GNAS314T > 324C, IGF2 intron3‐g.3072G > A or g. MC4R 1426G > A in Polish Landrace and Large White pigs. In the case of IGF2 intron3‐g.3072G > A, this information is of great importance, because this marker is widely implemented in pigs breeding and previous experiments suggested its role in prolificacy of pigs. We also investigated expression of IGF2 gene and showed that this gene is monoallelically expressed in reproductive organs (ovary and cornus uteri).  相似文献   

13.
The enormous production potential of buffaloes has never been accomplished due to various reproductive insufficiencies. Among them, post‐partum anoestrus, a multifactorial disorder, is predominant but any genetic association is yet to be established. This study focused to identify novel polymorphisms in heat‐shock protein 70 (HSP70) gene and its possible association with post‐partum anoestrus in Murrah buffaloes. A 579‐bp fragment from 5′ untranslated region of HSP70 gene was amplified by polymerase chain reaction from blood genomic DNA of 614 animals maintained under similar management conditions. In phase‐I experiment, custom sequencing and restriction enzyme (RE) digestion of the amplified fragment were performed in 40 buffaloes with similar post‐partum oestrous conditions over previous consecutive three or more gestations—20 animals each showing post‐partum anoestrus (>120 days after parturition) and normal cyclicity (<65 days after parturition). While in phase‐II experiment, herd screening by RE analysis was performed in remaining 574 animals. Four transversions at T‐75G, C+31G, T+38G and C+97A and three transition mutations at T‐153C, T+33C and A+44G positions were observed. Polymorphism at T+38G site revealed significant (p < .05) variation, where homozygous G was present only in post‐partum anoestrous animals while nucleotide T was present randomly in both groups of phase‐I animals whereas phase‐II experiments revealed homozygous G in 55 animals. Regression analysis in relation to average post‐partum interval against genotypic frequencies at T+38G also depicted significant association. HSP70 gene polymorphism at T+38G position can therefore be used as genetic marker for excluding probable post‐partum anoestrous buffaloes from herd for breeding programmes.  相似文献   

14.
Forty-six species were recorded in association with Patella spp., but most of these are casual associates, seeking temporary shelter. The shell surface offers an important substrate for algae.

The amphipod Hyale grandicornis is often associated with Patella, particularly in the juvenile stages. It is a facultative inquiline which vacates its hosts at high tide. The isopods Dynamenella australis and D. scabricula are predominantly associated with limpets and complete their life cycles under limpets. Choice chamber experiments demonstrate their preference for sheltering under limpets. The copepod Scutellidium patellarum is similar, but the association is more marked.

Calliopiella michaelseni (Amphipoda) is commensal and show a preference for certain limpet species. Its colour changes in relation to the host species. Feeding occurs on limpet faeces and algal fragments. The life cycle is completed under the limpet, two reproductive peaks occurring each year. Adults usually occur in pairs and there is a positive correlation between host and amphipod size. Juveniles remain with their parents initially, and then disperse to other limpets. Adult pairs may defend their host, excluding other amphipods. Calliopiella is strongly photonegative and thigmotactic.

The turbellarian Notoplanapatellarum is preferentially commensal with Patella oculus. This can be experimentally demonstrated. It feeds on small Crustacea, including Scutellidium.  相似文献   

15.
Post‐partum period has an important role in cows' breeding due to its effects on reproductive efficiency and subsequent pregnancy. Escherichia coli, Trueperella pyogenes (Arcanobacterium pyogenes), Fusobacterium necrophorum and Prevotella melaninogenicus are recognized as major pathogens associated with uterine endometrial lesions. The objective of this study was to identify these pathogens using the polymerase chain reaction (PCR) as a culture‐independent sensitive method. A total of 172 cows were examined 25–35 days post‐partum, and 128 cows were examined at 2 weeks later (39–49 days post‐partum). Uterine discharges were collected by covered plastic infusion pipettes. The prevalence of endometritis was greater in the first examination than the second (35.5% vs. 16%). E. coli was detected in eight of the samples, T. pyogenes was detected in 13 of the samples and F. necrophorum was detected in 11 of the samples. There was no positive sample of P. melaninogenicus. Uterine contamination by T. pyogenes and F. necrophorum in the first examination was higher than the second examination. T. pyogenes affected as a tendency the prevalence of clinical endometritis in first examination. Primiparous cows showed 4.02 times higher odds of clinical endometritis compared with second‐parity cows in first examination. A multiplex PCR protocol as a simple, less expensive, fast assay was introduced to identify E. coli, T. pyogenes and F. necrophorum.  相似文献   

16.
Psittacosis is a rare but potentially fatal zoonosis caused by Chlamydia psittaci, an organism that is typically associated with bird contact. However C. psittaci is capable of infecting other non‐avian hosts, such as horses, sheep, cattle and goats. Stud staff and veterinarians have significant exposure to parturient animals and reproductive materials in their routine work. To investigate the zoonotic potential associated with the emergence of C. psittaci as an abortifacient agent in horses, we established a programme of joint human and animal surveillance in a sentinel horse‐breeding region in Australia. This programme comprised cross‐notification of equine cases to public health agencies, and active follow‐up of known human contacts, including stud workers, foaling staff, veterinarians and laboratory staff. We identified no confirmed cases of acute psittacosis despite intensive surveillance and testing of heavily exposed contacts; however, further work in the area is needed.  相似文献   

17.
《African Zoology》2013,48(2):350-361
The yellow-bellied Scotophilus dinganii is the only African house bat species reported to occur in the Arabian Peninsula. Formerly, the Arabian house bats were referred to similar-looking white-bellied S. leucogaster, which differs from S. dinganii mainly by the colour of ventral pelage. We reassessed the taxonomic status of house bats from southwestern Yemen using genetic and morphological analyses. The Yemeni specimens clustered within two distantly related mitochondrial lineages of African Scotophilus: East African S. aff. dinganii, which is a paraphyletic group to S. dinganii s.str. from South Africa, andWest African S. leucogaster. This taxonomic assignation was based on published sequences of reference museum specimens. Differences in external and cranial measurements also indicated the presence of two distinct taxa in Yemen. The Yemeni and comparative Ethiopian populations of S. aff. dinganii showed close morphological similarity to the type specimen of S. nigrita colias from Kenya. Because the Yemeni and Ethiopian yellow-bellied house bats cannot be synonymized with S. dinganii, the designation S. colias is tentatively suggested for this particular East African and Yemeni lineage of the S. dinganii complex. However, final correspondence of this name with the respective populations or applicability of some of other available names must yet be explored. Based on environmental differences of the Yemeni localities of origin, S. colias appears to be ecologically delimited to mountainous habitats, while S. leucogaster to harsh lowland deserts. This is consistent with known habitats of African populations of both species.  相似文献   

18.
The aim of this study was to demonstrate that seroreactivity against Leptospira is significantly associated to the reproductive efficiency of recipient mares of an embryo transfer (ET) programme. A serosurvey was conducted from August 2007 to March 2009 in five herds from Rio de Janeiro, Brazil, with high rates of reproductive failure, as early embryonic death (>12%), abortion (>12%) and perinatal death. Detailed information about the losses was obtained from practitioner. A total of 338 recipient mares were tested by microscopic agglutination test, and 226 (66.9%) were seroreactive, mainly against serovars Bratislava and Copenhageni. Seroreactivity could be associated to reproductive failure (p < 0.001), and it was demonstrated that a seroreactive mare is 1.8 times more likely (relative risk – RR) to present reproductive failure than a seronegative one, particularly in relation to early embryonic death (p < 0.0001; RR 8.4) but also to abortions (p < 0.0001; RR 3.5), and to perinatal death (p < 0.05; RR 7.3). Therefore, seroreactivity to Leptospira is associated to reproductive failure in all phases of pregnancy in recipient mares, impairing equine ET programmes.  相似文献   

19.
The aims were to evaluate sperm DNA fragmentation (SDF) in boars through the dispersion of their chromatin in raw semen samples, quantifying the extent of SDF, and to assess dynamic aspects of sperm DNA damage after incubation to obtain the rate of sperm DNA fragmentation (rSDF) under thermal conditions similar to the uterus (37°C) over a period of up to 24 hr and to correlate the reproductive outcome of the sows with the SDF of the boars at ejaculation. The study was performed on a pig‐breeding farm in southern Uruguay. Sixty‐one ejaculates from five of the most frequently used hybrid boars were evaluated. Semen was collected weekly from each of the boars, using the gloved‐hand technique and discarding the jelly‐like fraction of the ejaculate. Fresh semen was kept in a water bath at 37°C and protected from light, and was thereafter processed with Sperm‐Sus‐Halomax® to evaluate SDF. The smears for time 0 (T0) were made on farm, and thereafter smears were made at the laboratory at 4 hr of obtaining the semen (T4), then every 2 hr (T6, T8, T10, T12) and a final fixation at 24 hr (T24). Differences in SDF were observed among exposure times for all boars (p < .05), but not between T10 and T12 (p = .7751) nor T4 and T24 (p = .9113). In none of the T24 samples, sperm heads could be seen with chromatin dispersion halos. Furthermore, there were differences among boars when comparing sperm rSDF (p < .05). Farrowing rate was not affected by SDF at T0 (r = .38, p = .75), nor was litter size (r = .16, p = .70). With the present experimental conditions, we have not been able to show a relationship between sperm DNA fragmentation at ejaculation and reproductive performance. However, this could be a result of the low number of ejaculates and boars used.  相似文献   

20.
The objective of the present investigation was to estimate the seroprevalence T. gondii infection in breeding sows in Western Fujian Province, the People’s Republic of China. Sera collected from breeding sows during 2006–2007 from 6 different regions in Western Fujian Province were assayed for antibodies to T. gondii by an indirect hemagglutination antibody (IHA) test. Antibodies to T. gondii were detected in 87 (14.38%) of 605 breeding sows. Differences in seroprevalence were observed between sampling regions, ranging from 10.14% to 37.50%. The present investigation demonstrated that the prevalence of T. gondii infection in breeding sows in Fujian Province was high. Integrated control strategies and measures should be implemented to prevent and control T. gondii infection in breeding sows, which in turn will have significant implications for the control of human infection with T. gondii in this province.  相似文献   

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