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1.
The serum antibody activity toPsoroptes ovis antigens, as determined by enzyme-linked immunosorbent assay (ELISA), was monitored during the development and decline phase of scabies in cattle herds under feedlot conditions in an endemic (Bushland) and a nonendemic (Kerrville) scabies area of Texas. The infestations were initiated by exposing six calves in each of the herds toP. ovis and allowing the infestations to spread to other members of the herd. The cattle in the endemic area developed more lesions and a higher incidence of the disease than did the cattle in the nonendemic area; also, there were more cattle with specific serum antibody activity in the Bushland herd than in the Kerrville herd at the peak of the infestations (late January-early February). As infestations declined because of summer latency, the number of calves with specific serum antibody activity declined in both herds. Specific serum antibody activity disappeared in the Kerrville cattle whenP. ovis was no longer detected. However, specific serum antibody activity was still detected in some of the Bushland cattle in late summer (August) and fall (October) examinations, when low numbers ofP. ovis were detected. These results indicate that the ELISA would be very useful in detection of specific serum antibody activity in lightly infested calves, especially during the developmental and decline phases of the disease.  相似文献   

2.
An enzyme-linked immunosorbent assay (ELISA) to detect cattle grub-infested animals in the autumn in Alberta has been developed. Antibody to Hypoderma lineatum de Vill. was detectable as early as 6 weeks post-infestation in artificially infested steers. Peak antibody concentrations preceded the peak in maximum 'apparent' grub numbers which occurred between 37 and 43 weeks after infestation. Natural infestations with H. lineatum and H. bovis L., ranging from one to ninety-two grubs per calf, were readily detected by November and the incidence of false positives in uninfested calves was only 5%. Low level (1-4 grubs) infestations of H. bovis only became detectable in February with peak antibody concentrations occurring at the end of April. Prevalence of cattle grub infestations in southern Alberta was shown to be 37% during this study.  相似文献   

3.
Differences in ketosis and clinical mastitis rates, mean somatic cell counts (SCC) and reproductive performance scores (fertility status index = FS-index) between herds housed in free stall (n = 533) and tie stall (n = 59) barns were measured in relation to management and environmental factors in a retrospective cohort study of Norwegian dairy farms with automatic grain feeding systems. Herds with tie stalls were found to have a higher clinical mastitis rate, (61.6 cases per 100 cow-years versus 46.4 cases per 100 cow-years (p<0.01)); a significantly higher proportion of herds with ketosis, (relative risk = 1.59, (p<0.01)); and a lower mean fertility status index, (67.3 versus 82.8 (p<0.01)). No significant difference in mean SCC was found between the 2 groups of dairies (p = 0.32). Large herds had higher Loge geometric mean SCC than small herds (p<0.01) and herds with high SCC had lower milk production than herds with low SCC (p<0.01). Herds that scored “very good” on cow cleanliness had significantly lower adjusted mean SCC than herds with scores of “average” or “good” (p<0.05). Herds in barns with a concrete floor had an adjusted mean number of cases of clinical mastitis of 51.4 per 100 cow-years, 14 per cent higher than herds in barns with rubber mats, litter bed or wood (45.2 cases per 100 cow-years) (p<0.05). Herds with high milk production level had higher FS-index than herds with low milk production (p<0.01). Lower disease rates and the higher fertility status measured in the present study favor free stall herds over tie stall herds.  相似文献   

4.
In a 20-year-survey, 9364 dairy cattle in 324 herds kept under a zero-grazing management, 1252 beef cattle in 46 herds grazing all the year round, 3347 sheep in 134 herds (only 26 are grazing herds), and 872 goats in 47 herds (only 20 are grazing) were examined. The mites collected from cattle were identified as Chorioptes texanus only, and those from sheep, goats and gazelles were identified as C. bovis. Chorioptic mange was not diagnozed in grazing beef cattle, ibexes and housed animals (as compared to grazing herds), and in rams and billy goats. Holstein-Israeli bulls kept in insemination centres were not clinically infested, whereas four Charolais bulls were infested with chorioptic mange. Infestation rate was higher in older animals than in younger ones. Hoggets and young goats over 10 months and heifers over 13 months were found clinically infested with Choriopic mites. Lesions were not usually extensive and occurred mainly in predilection sites. The ocular form in sheep and the groin form in goats are very uncommon and apparently are reported for the first time. Chorioptic mange was recorded generally throughout the year. In our study seasonal distribution could not be demonstrated in cattle, while in sheep and goats the highest infestation rate occurred in February to March and the lowest in August and September.  相似文献   

5.
Biting dog lice (Trichodectes canis) were first detected on wolves (Canis lupus) in Southcentral Alaska (USA) in 1981 introduced via domestic dogs. Lice infestation expanded north via wolf dispersal to the Tanana Flats of Interior Alaska in December 2003. Effects of this ectoparasite on wolves were persistent with moderate to severe clinical signs of pediculosis lasting multiple generations. Our objectives were to evaluate the extent of lice infestation on wolves within the Tanana Flats and develop a management program that limited further transmission. We implemented a treatment method that consisted of multiple applications of oral antiparasitic ivermectin-injected baits aerially distributed at den and rendezvous sites during mid-May through August. During 2005–2010, we evaluated 12–19 packs annually as part of a treatment group and 3 infested packs as a control. Infestation rates of treatment packs prior to treatment varied from 15% in 2005 (2 of 13), 50% in 2006 (7 of 14), 24% in 2007 (4 of 17), 5% in 2008 (1 of 19), and 0% in 2009–2010 (0 of 19). We treated 50%, 71%, and 75% of the infested treatment packs during 2005–2007, respectively. All treated packs were lice-free the winter following treatment, whereas all 3 control packs remained infested. The combination of treatment and harvest successfully eliminated the local source population of lice within 3 years and we found no evidence of lice infestation within the treatment area during the last 3 years of the study. By using this treatment method, managers can eliminate dog lice infestations of wolves in areas ≤13,000 km2. By initiating treatment promptly after detection, transmission to unexposed nearby packs can be postponed and the local source population of lice on wolves eradicated. © 2013 The Wildlife Society.  相似文献   

6.
The present study was conducted to determine the prevalence of hard tick infestations in cattle of Mizoram from April 2017 to March 2018. The prevalence of hard tick infestations was studied in relation to sex and age of animals and seasonal changes in a year. Cattle of selected places were examined carefully for the presence of ticks and in positive cases ticks were collected manually and identified on the basis of morphological characters. A total of 713 cattle were examined and out of which 452 (63.39%) cattle were found to be infested with hard ticks and the prevalent tick species was Rhipicephalus (Boophilus) microplus. A significantly (p < 0.01) higher infestation was observed in female cattle (66.43%) than males (48.83%). Age-wise highest prevalence of tick infestations was found in 1–5 years (73.41%) age group followed by >5 years age group (61.92%) and < 1 year (42.65%) age group, respectively. Seasonally, the prevalence of hard tick infestation was found highest (p < 0.01) in monsoon (77.91%) and lowest in winter (43.16%). The present study provides data on tick infestation in cattle of Mizoram, India.  相似文献   

7.
A rodent ectoparasite survey was made in the city of Belo Horizonte, Minas Gerais, Brazil, from June 1980 to September 1982. The species of ectoparasites captured from 950 Rattus norvegicus norvegicus were: Xenopsylla cheopis, Ctenocephalides felis felis, Polyplax spinulosa, Laelaps nuttalli, Echinolaelaps echidninus and Atricholaelaps glasgowi, the last species only represented by three specimens interchanged with wild rodent. P. spinulosa and L. nuttalli, although cosmopolitan, are recorded for the first time in State of Minas Gerais. The sex ratio of the ectoparasites, as well as the prevalence of fleas, mites and lice on the separate sexes of rodents are presented. 66.9% of the rats were infested by mites, almost twice more than infestations by fleas and louse jointly (39%). L. nuttalli was found in great numbers and presented the highest index of infestation: 55.1%. Single infestations are as common as associated ones. P. spinulosa, contrary to L. nuttalli, rarely occurs in single infestation. Data on the distribution of the ectoparasites on the rodents are also reported. The infestation observed in Belo Horizonte is confronted with those obtained by other authors in different places.  相似文献   

8.
The prevalence of infestation with head lice and body lice, Pediculus spp. (Phthiraptera: Pediculidae) and pubic (crab) lice Pthirus pubis (L.) (Phthiraptera: Pthiridae), was recorded from 484 people in Nepal. The prevalence of head lice varied from 16% in a sample of people aged 10-39 years of age, to 59% in street children. Simultaneous infestations with head and body lice (double infestations) varied from 18% in slum children to 59% in street children.  相似文献   

9.
Approximately 88% of Norwegian dairy cattle are housed in tie stalls. Free stall housing for all dairy cattle will be implemented within 20 years. This means that the majority of existing stalls will be rebuilt in the near future. Fifty-seven free stall herds of the Norwegian Red breed were randomly selected and 1547 cows and 403 heifers were trimmed by 13 claw trimmers during the late winter and spring of 2002. The claw trimmers had been taught diagnosing and recording of claw lesions. Environment, management- and feeding routines were also recorded. Fifty-three herds had concrete slatted alleys while 4 had solid concrete. Thirty-five herds had concrete as a stall base, while 17 had rubber mats, 2 had wood and 3 had deep litter straw beds. The prevalence of lameness was 1.6% in hind claws. Models for lameness and claw lesions were designed to estimate the influence of different risk factors and to account for the cluster effects within herd and claw trimmer. Detected risk factors for lameness were: parity three and above and narrow cubicles; for heel horn erosions: lactation stage around 5–7 months after calving and solid concrete alleys; for haemorrhages of the white line: lactation stage around 3–5 months after calving and solid concrete alleys; for haemorrhages of the sole: parity one, lactation stage around 5–7 months after calving and short cubicles, for white line fissures: slatted concrete alleys; for asymmetrical claws: parities two and above and for corkscrewed claws: solid concrete alleys. The prevalence of lameness in heifers was low, however 29% had one or more claw lesions. Heifers that were housed in pens or free stalls had more heel-horn erosions, haemorrhages of the sole and white-line fissures than heifers in tie stalls. As new free stalls are being built, it is important to optimise the conditions for claw health.  相似文献   

10.
Proteins extracted from salivary glands of unfed, three days and five days fed adult Hyalomma marginatum marginatum were analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). We have noticed changes during the three feeding steps. Some proteins disappeared during feeding process (23, 38, 39, 40 to 50, 95 and 112 kDa), they might be proteins which were converted in other substances and are secreted. Other antigens (13 to 14, 20, 25, 29, 165 and 210 kDa) were synthesized as a result of tick attachment and feeding. They may be related to growth and development or are the ciment which fixed the adult. Also, three Holstein calves were infested five times with 100 pairs of adult ticks of the same species. The five infestations were performed two weeks from the previous infestation. The sera before infestations and after each infestation were used in western-blot analyses to identify antigens from five days salivary gland extracts of the primary infestation of ticks. Three antigens (18.7, 50 and 80 kDa) were revealed weakly after the first and the second infestations by sera samples but not at infestation onward. Others (13.5, 17 to 18.5, 25, 30, 70, 133, 176 and 193 kDa) were revealed only by sera taken after manifestation of resistance (third infestation). A 13.5 kDa antigen was particularly revealed when resistance had appeared and became more evident after the fourth and fifth infestations. The late antigens recognized might be associated with establishment of calves resistance against ticks.  相似文献   

11.
In a cross-sectional survey in February-May 2019, the prevalence of Pediculosis capitis with demographic data and the behavioral practices were investigated among 750 participants in the Eastern region of Saudi Arabia. Female participation was highly remarked with a percentage of 94.08% compared to that of male one about 5.91%. A deficiency of knowledge about lice infestation was noted especially among illiterate participants raised from their socio-economic levels (p-value = 0.001). Lice infestation reached higher rates in children aged less than 20 years with itching of the hair scalp. The obtained results revealed that 59.33% of the respondents believed that frequency of personal hygiene and washing of hair were the best methods for preventing the lice infestation. However, the treatment of lice infestation using anti-lice agents (p-value = 0.020) was preferred by 14.26% of participants. Although knowledge about the preventive tools for lice infestation (p-value 0.089) was not significantly associated with the experience of infestation but knowledge about the appropriate treatment to kill lice (p-value 0.020) and the wrong practices in the treatment of a head lice infestation were (p-value 0.005) significantly associated with the experience of infestation. Health programs and campaigns preventions are highly advised to increase the awareness of Pediculosis capitis with an effective strategic plan to control, manage, and prevent this disease.  相似文献   

12.
Major ectoparasites of cattle in and around Mekelle, northern Ethiopia   总被引:2,自引:0,他引:2  
Studies on the identification of major ectoparasites of cattle in and around Mekelle in northern Ethiopia were carried out from November 2006 to June 2007. Ectoparasite prevalence, infestation, and the possible risks associated with ectoparasites were investigated. Data collected were analyzed using the χ2‐test. A total of 849 cattle were examined: 40.2% (341), 53.2% (452) and 5.9% (50) were infested with ticks, lice and Demodex, respectively. A positive correlation was observed between prevalence and production system and breed of cattle. The results also revealed widespread occurrence of ectoparasites that have affected the general health and productivity of cattle in the study area. Seven different species of ticks were found on the cattle, with some capable of transmitting pathogens harmful to both cattle and humans.  相似文献   

13.
Little is known about the population genetics of the louse infestations of humans. We used microsatellite DNA to study 11 double infestations, that is, hosts infested with head lice and body lice simultaneously. We tested for population structure on a host, and for population structure among seven hosts that shared sleeping quarters. We also sought evidence of migration among louse populations. Our results showed that: (i) the head and body lice on these individual hosts were two genetically distinct populations; (ii) each host had their own populations of head and body lice that were genetically distinct to those on other hosts; and (iii) lice had migrated from head to head, and from body to body, but not between heads and bodies. Our results indicate that head and body lice are separate species.  相似文献   

14.
The purpose of this field study was to develop and evaluate eradication as a strategy to control lice in cattle. Thirty-three herds of cattle were selected and observed during a period of two and a half years. Before eradication, biting lice (Damalinia bovis) were present in 94% of the herds and 27% of the animals. Sucking lice (Linognathus vituli) were present in 42% of the herds and 5% of the animals. These levels were very similar to those reported from other countries in Northern Europe.  相似文献   

15.
To determine whether pinworm infections and head lice infestations spread among children in orphanages, 117 children from 4 orphanages in Busan-si and Ulsan-si, Korea, were examined for enterobiasis and head lice infestation between January and February 2014. The overall rate of Enterobius vermicularis egg positivity was 0.85%, whereas none of the children had head lice infestations. The rate of pinworm infection was much lower among the orphanage children compared to the rates observed in previous studies among kindergarten and primary school students. Moreover, the risk factors for enterobiasis were less frequent among these subjects than previously reported. The personal hygiene and health of the orphanage children were supervised by a regular, employed nurse through a health education program. In conclusion, pinworm infection was efficiently controlled among the children in orphanages, and this might be related to good personal hygiene practices in Korea.  相似文献   

16.
A louse survey based on samples of cut hair collected from floors of barbershops and beauty parlors was conducted in Belo Horizonte, Minas Gerais State, Brazil, from October 1984 to April 1985, as an alternative way to determine the prevalence of pediculosis capitis in the population. Of 475 samples examined for nits, nymphs, or adults of Pediculus capitis, 140 were infested (29.5%). A total of 58 lice and 3,553 nits were found in 33,632.9 g of hair collected, giving a ratio of 0.10 nit/g. Almost 29% of the nits were viable and capable of being transmitted after hatching. There was significant difference among the infestation rates by socioeconomic levels, and samples from barbershops with male customers were the most infested. Based upon the number of haircuts in each sample, we estimated that 5 or 6% of the population might be infested by this species.  相似文献   

17.
Tick abundance and seroconversion rates of 640 indigenous cattle in a mixed crop-livestock system in Uganda were investigated in a 14 months longitudinal study. Up to 100% of the cattle in Buyimini, Kubo, Nanjeho, Ojilai and Sitengo villages (high tick challenge zone) were consistently infested with Rhipicephalus appendiculatus, whereas on average 50% of the cattle in Bunghaji, Hitunga and Magoje villages (low tick challenge zone) were inconsistently infested. Likewise, up to 50% of the cattle in Buyimini, Kubo, Nanjeho, Ojilai and Sitengo villages were consistently infested with R. (Boophilus) decoloratus ticks, while on average 30% of the cattle in Bunghaji, Hitunga and Magoje were inconsistently infested. Seroconversion rates of cattle to Anaplasma marginale infection under low tick challenge were higher than those under high tick challenge, but the reverse was true for Babesia bigemina infection. For Theileria parva infection, seroconversion rates of cattle older than 6 months under low tick challenge were significantly higher than those under high tick challenge (P < 0.05). However, the likelihood of occurrence of theileriosis cases among calves (0-6 m) under high tick challenge was 6 times (Odds ratio = 5.82 [1.30-36.37]) higher than under low tick challenge. The high density of anti-tick plants Lantana camara and Ocimum suave that were widespread in villages with low tick challenge, among other factors, was probably the cause for unfavourable tick survival.  相似文献   

18.
The occurrence of hide damage light flecks and spots was determined on tanned hides from 28 herds during a period of 8 to 12 months. Light flecks and spots are described as small areas of grain loss up to 3 mm in diameter that are seen on dyed crust cattle leather. Damage was found on 75.8% of all hides. The neck and shoulders were the anatomical region with the highest prevalence of damage. Sixty-eight per cent of all hides had light flecks and spots in this region. The forelimbs and dewlap were the anatomical region with the second highest occurrence with a prevalence of 39.1%. This distribution corresponded to the known distribution of lice in cattle. No significant differences were observed in age, sex, prevalence of lice in the herd assessed in March or infestations with different lice species. The frequency of light flecks and spots varied significantly during the year. The frequency was highest in the late winter and early spring, decreased significantly during the summer and was lowest in the autumn. This variation supported the importance of lice in the development of light flecks and spots and suggested a relatively long healing period for the damages induced by lice.  相似文献   

19.
Lice-infected sea trout populations were monitored using fish traps in the Romsdalsfjord (Norway). The reliability and efficiency of this capture technique, which allows estimation of lice infestation rates without killing the fish, was evaluated through a mark–recapture study. A total of 2447 sea trout smolts were captured, tagged and released over a three-year period. There was a considerable variation in capture rates (range: 0.4–17.7 fish per day) and sea lice numbers (number of lice per fish: 2.8–30.3; number of lice per gram body weight: 0.02–0.69) among localities, sampling times and years. Recapture rates of tagged fish with traps, which were low (2% or 0.11 fish per day), showed that the risk for pseudoreplication was minor, in terms of counting lice on the same fish several times. Most of the tagged sea trout (90%) were recaptured within the first two months after release, and no significant variations in lice numbers were found between tagging and recapture. The lack of differences in lice levels between tagging and recapture during the first week after tagging indicated that the method most likely would not significantly underestimate the lice infestations due to loss of lice during handling. Therefore, our results confirm that the use of fish traps is a suitable method for estimation of lice numbers on wild salmonids.  相似文献   

20.
A questionnaire was sent to 1500 randomly selected dairy herds in Sweden, asking for general information about the herds, including routines from birth to first calving and also routines at breeding, calving and during the grazing period. Fifty-eight percent of the questionnaires were returned. The preweaned calves were kept in individual calf pens in 68% and in group housing systems in 28% of the herds. Pens with slatted floors were the main housing system for replacement heifers from weaning to breeding, and tie stalls from breeding to first calving. Whole milk was used in 44% and milk replacements in 42% of the herds. The calves received, as a median, 2.5 litres of milk per meal and 2 meals per day. The median age at weaning was 8 weeks. Age was the single most common criteria used for deciding both weaning and breeding time. The median age when the heifers were first turned out to pasture was 6 months. Prophylactic anthelmintic treatment was used by 65% of the herds. The most common diet for replacement heifers before calving was a combination of grain, hay and silage.  相似文献   

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