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81.
Abstract

AIMS: To ascertain the levels of awareness of legislation governing the welfare of cats, and provision of basic care, including vaccination, by cat-owners within two locations in New Zealand. To assess the ability of respondents to differentiate between the terms ‘stray’ and ‘feral’.

METHODS: A face-to-face questionnaire, consisting of 12 questions in three sections, was distributed by volunteers within Auckland (n=255) and Kaitaia (n=99) to gather information pertinent to the study's aims. Section 1 covered respondents’ personal details; Section 2, ownership and care of cats, including whether or not the cats were vaccinated against feline immunodeficiency virus (FIV) and feline leukaemia virus (FeLV); and Section 3, awareness of legislation and differences between the terms ‘stray’ and ‘feral’.

RESULTS: Overall, fewer than half of respondents were aware of the animal welfare legislation within New Zealand or the semantic differences between the terms ‘stray’ and ‘feral’ as they appear in the dictionary. Respondents ≥41 years old, and individuals employed in the animal-related sector, were significantly more likely to be aware of the legislation and make the correct distinction between the terms compared with those aged ≤40, and those working in a non-animal-related profession.

A significantly greater percentage of cat-owners (42%) provided care for cats they did not own compared with non-owners (26%). Results also indicated a large majority of cat-owners may consider standard annual vaccinations to include vaccination against FIV and FeLV.

CONCLUSION: Dissemination of information about animal welfare legislation is important for the care of cats within New Zealand, and the definitions of the terms ‘stray’ and ‘feral’ need to be more clearly stated in order to prevent confusion. This is especially important when cats may be controlled using lethal measures under different legislative precedents that are not necessarily consistent with one another.

CLINICAL RELEVANCE: Veterinary clinics may act as a primary source for the dissemination of information about relevant welfare acts as well as preventative health care, thus improving the welfare of cats. Cat-owners need to be better educated about the diseases covered by annual vaccination.  相似文献   
82.
An early understanding of behavioral suitability for guiding work in domestic dogs (Canis familiaris) would be useful for organizations which train dogs as mobility aids, such as the Guide Dogs for the Blind Association. We explored the potential for a standardized test of behavior in young dogs to reflect subsequent success in guide dog training. Five hundred eighty-seven potential guide dogs were exposed to a series of eight stimuli at 6-8 weeks of age. The responses of dogs were scored on a 7-point scale according to either responsiveness to human assessor or to environmental stimuli, on stimuli comprising following when called; retrieve; gentle restraint; noise; stroking; a moving toy squirrel; encouragement to go through a tunnel; and encouragement to go over a ramp. Five of these stimuli showed some association with success in guide dog training, and three of these stimuli could be usefully combined in a logistic regression model of success in training. There is potential for this test to be used to predict suitability for guiding work but adjustments to the scoring protocol are recommended.  相似文献   
83.
The plasmodiophoromycete Polymyxa betae is an obligate root parasite that transmits Beet necrotic yellow vein virus (BNYVV), the cause of sugar beet rhizomania disease. Currently, control of this disease is achieved through the use of cultivars with monogenic (Rz1) partial resistance to the virus. To improve the level and durability of this resistance, sources of resistance to the virus vector, P. betae, were sought. Over 100 accessions of the wild sea beet (Beta vulgaris ssp. maritima) from European coastal regions were evaluated for resistance in controlled environment tests. Quantification of P. betae biomass in seedling roots was achieved using recombinant antibodies raised to a glutathione‐s‐transferase expressed by the parasite in vivo. Several putative sources of resistance were identified and selected plants from these were hybridized with a male‐sterile sugar beet breeding line possessing partial virus resistance (Rz1). Evaluation of F1 hybrid populations identified five in which P. betae resistance had been successfully transferred from accessions originating from Mediterranean, Adriatic and Baltic coasts. A resistant individual from one of these populations was backcrossed to the sugar beet parent to produce a BC1 population segregating for P. betae resistance. This population was also tested for resistance to BNYVV. Amplified fragment length polymorphism and single‐nucleotide polymorphism markers were used to map resistance quantitative trait loci (QTL) to linkage groups representing specific chromosomes. QTL for resistance to both P. betae and BNYVV were co‐localized on chromosome IV in the BC1 population, indicating resistance to rhizomania conditioned by vector resistance. This resistance QTL (Pb1) was shown in the F1 population to reduce P. betae levels through interaction with a second QTL (Pb2) found on chromosome IX, a relationship confirmed by general linear model analysis. In the BC1 population, vector‐derived resistance from wild sea beet combined additively with the Rz1 virus resistance gene from sugar beet to reduce BNYVV levels. With partial virus resistance already deployed in a number of high‐yielding sugar beet cultivars, the simple Pb1/Pb2 two‐gene system represents a valuable additional target for plant breeders.  相似文献   
84.
Diseases of the reproductive tract are a frequent problem in dairy herds. Herpesviruses are uterine pathogens also involved in other clinical diseases; for example, bovine herpesvirus type 4 BoHV‐4 induces abortion, enteritis, metritis, pneumonia and vaginitis, but it can also be detected in healthy cows. The role of BoHV‐4 in the development of clinical endometritis (CE) or subclinical endometritis (SE) has not clearly been described. Therefore, the objective of this study was to describe the prevalence of uterine BoHV‐4 infection and its relationship with clinical, bacteriological and cytological findings in dairy cows 20–30 days after calving. The experiment was performed as a completely randomized block design, with farm (= 10) as blocking criterion and with cow (= 397) as the experimental unit. Logistic regression models were used to assess the effect of BoHV‐4 infection on CE, SE and reproductive performance. Proportion of cows infected with BoHV‐4 was 5.8% (= 23/397). BoHV‐4 was isolated in 11.0% (= 12/109), 4.8% (= 4/84) and 3.6% (= 7/194) of cows diagnosed as CE, SE or healthy, respectively. A logistic model revealed that BoHV‐4 infection showed a tendency to increase the risk for CE (AOR = 2.17; = .10) but significantly reduced both, the odds for artificial insemination within 80 days post‐partum (dpp) (AOR = 0.37; = .035) and for pregnancy within 200 dpp (AOR = 0.13; = .004). Furthermore, BoHV‐4 infection increased the chance for intrauterine infection with Trueperella pyogenes (AOR = 5.55; < .001) and vice versa (AOR = 5.79, < .001). In conclusion, BoHV‐4 infection is associated with reduced chances for insemination and pregnancy by 200 dpp and showed a trend to be associated with increased risk for CE. Furthermore, BoHV‐4 and Trueperella pyogenes infections are strongly related.  相似文献   
85.

Background

Reproductive interference can mediate interference competition between species through sexual interactions that reduce the fitness of one species by another. Theory shows that the positive frequency-dependent effects of such costly errors in mate recognition can dictate species coexistence or exclusion even with countervailing resource competition differences between species. While usually framed in terms of pre-mating or post-zygotic costs, reproductive interference manifests between individual Caenorhabditis nematodes from negative interspecies gametic interactions: sperm cells from interspecies matings can migrate ectopically to induce female sterility and premature death. The potential for reproductive interference to exert population level effects on Caenorhabditis trait evolution and community structure, however, remains unknown.

Results

Here we test whether a species that is superior in individual-level reproductive interference (C. nigoni) can exact negative demographic effects on competitor species that are superior in resource competition (C. briggsae and C. elegans). We observe coexistence over six generations and find evidence of demographic reproductive interference even under conditions unfavorable to its influence. C. briggsae and C. elegans show distinct patterns of reproductive interference in competitive interactions with C. nigoni.

Conclusions

These results affirm that individual level negative effects of reproductive interference mediated by gamete interactions can ramify to population demography, with the potential to influence patterns of species coexistence separately from the effects of direct resource competition.
  相似文献   
86.
Gilt oestrus and ovulation responses to injection of a combination of equine chorionic gonadotrophin (eCG) and human chorionic gonadotrophin (hCG) (PG600) can be unpredictable, possibly reflecting inadequate circulating LH activity. The objective of this study was to determine the effect of PG600 followed by supplemental hCG on gilt ovarian responses. In experiment 1, 212 Hypor gilts (160 day of age) housed on two farms in Spain received intramuscular (i.m.) injections of PG600 (n = 47), or PG600 with an additional 200 IU hCG injected either concurrently (hCG‐0; n = 39), or at 24 h (hCG‐24; n = 41) or 48 h (hCG‐48; n = 45) after PG600. A further 40 gilts served as non‐injected controls. Ovulation responses were determined on the basis of initial blood progesterone concentrations being <1 ng/ml and achieving >5 ng / ml 10 d after the PG600 injection. The incidence of ovulating gilts having progesterone concentrations >30 ng/ml were recorded. During the study period, 10% of control gilts ovulated whereas 85–100% of hormone‐treated gilts ovulated. There were no significant differences among hormone groups for proportions of gilts ovulating. The proportions of gilts having circulating progesterone concentrations >30 ng/ml were increased (p ≤ 0.02) in all hCG treated groups compared with the PG600 group. In experiment 2, a total of 76 Hypor gilts at either 150 or 200 days of age were injected with PG600 (n = 18), 400 IU eCG followed by 200 IU hCG 24 h later (n = 20), PG600 followed by 100 IU hCG 24 h later (n = 17), or 400 IU eCG followed by 300 IU hCG 24 h later (n = 21). Blood samples were obtained 10 days later for progesterone assay. There were no effects of treatment or age on incidence of ovulation, but fewer 150‐day‐old gilts treated with PG600 or 400 IU eCG followed by 200 IU hCG had progesterone concentrations >30 ng / ml. We conclude that hCG treatment subsequent to PG600 treatment will generate a higher circulating progesterone concentration, although the effect is not evident in older, presumably peripubertal, gilts. The mechanism involved and implications for fertility remain to be determined.  相似文献   
87.
The aim in this study was to investigate corpus luteum function and embryonic loss in buffaloes mated by artificial inseminations (AI) during the transitional period from breeding to non‐breeding season. The study was carried out using 288 multiparous Italian Mediterranean Buffalo cows at 110 ± 4 days in milk. The buffaloes were mated by AI after synchronization of ovulation by the Ovsynch‐TAI protocol 25 days after AI buffaloes underwent trans‐rectal ultrasonography to assess embryonic development. Pregnancy diagnosis was confirmed on Days 45 and 70 after AI by rectal palpation. Buffaloes pregnant on Day 25 but not on Day 45 were considered to have undergone late embryonic mortality (LEM), whilst buffaloes pregnant on Day 45 but not on Day 70 were considered to have undergone foetal mortality (FM). Corpus luteum size and blood flow were determined by real‐time B‐mode/colour‐Doppler on day 10 after AI in 122 buffaloes. The resistive index (RI) and pulsatility index (PI) were recorded at the time. Milk samples were collected on Days 10, 20 and 25 after AI in all inseminated buffaloes for the assay of whey P4 concentrations. Data were analysed by anova . Pregnancy rate on Day 25 after AI was 48.6% (140/288) and declined to 35.4% (102/288) and 30.6% (88/288) by Day 45 and Day 70 respectively. The incidences of LEM and FM were respectively 27.1% (38/140) and 13.7% (14/102). Pregnant buffaloes had greater (p < 0.01) whey concentrations of P4 from Day 20 onwards than buffaloes which showed LEM, whilst P4 in buffaloes that showed FM did not differ from the other two groups on Day 10 and Day 20. Corpus luteum blood flow on Day 10 after AI showed higher RI (p < 0.05) and PI (p = 0.07) values in buffaloes that subsequently were not pregnant on Day 25 compared with pregnant buffaloes. Buffaloes that were not pregnant on Day 45 also had a higher (p = 0.02) RI value on Day 10 than pregnant buffaloes, whilst PI values on Day 10 did not differ for the two groups of buffaloes. It was concluded that blood flow to the corpus luteum on Day 10 after AI influences corpus luteum function as judged by P4 secretion and also embryonic development and attachment in buffaloes.  相似文献   
88.
89.
The histochemical fluorescence of those neurons in brainstem raphe nuclei which are presumed to contain serotonin is selectively and stereospecifically enhanced by L-tryptophan at doses that also produce an elevation in the concentration of serotonin. However, contrary to our assumptions, the increase in raphe fluorescence is not prevented by p-chlorophenylalanine, an inhibitor of serotonin synthesis. These results suggest that under some conditions derivatives of tryptophan other than, or in addition to, serotonin may be of significance in raphe neurons.  相似文献   
90.
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