Aspects of the ecology of the Asian tapeworm, Bothriocephalus acheilognathi Yamaguti, 1934 in yellowfish in the Vaal Dam, South Africa

Seasonal surveys were conducted at the Vaal Dam between April 2000 and January 2001. Twenty smallmouth yellowfish (Labeobarbus aeneus) and 20 largemouth yellowfish (Labeobarbus kimberleyensis) were collected with the aid of gill nets. Surface water quality variables were included. The cestodes were identified as either Bothriocephalus acheilognathi Yamaguti, 1934 or "other cestode spp.". The majority (99.8%) of the cestodes found in both yellowfish species were identified as B. acheilognathi (Asian tapeworm). The prevalence, mean intensity and abundance of B. acheilognathi in both yellowfish species were calculated. Ecological parameters including species specificity, seasonality, gender specificity and relationships between fish size and the Asian tapeworm prevalence were also included. In this study, B. acheilognathi preferred L. kimberleyensis over L. aeneus although a low intensity was observed in smallmouth yellowfish. Furthermore, the infection (in terms of prevalence, abundance and mean intensity) in largemouth yellowfish was markedly higher. Seasonal patterns observed in the Asian tapeworm's infection of smallmouth yellowfish are attributed to breeding and subsequent feeding patterns of this fish species with relatively high infections recorded in winter and spring. For L. kimberleyensis no explanation can be given regarding the seasonal patterns observed for the mean intensity and abundance of B. acheilognathi. The maximum and minimum mean intensity and abundance values in largemouth yellowfish were recorded in autumn and spring, respectively. In addition, the prevalence of B. acheilognathi was consistently high in all four seasons.     

Relationship between Length of Roundtail Chub and Infection Intensity of Asian Fish Tapeworm Bothriocephalus acheilognathi

Abstract

Nonnative parasites have been blamed for the decline of native fish species in the American Southwest. The Asian fish tapeworm Bothriocephalus acheilognathi has parasitized many native fish species, but little is known of its effects on native cyprinid fish hosts. I found a strong negative correlation (Spearman's rank correlation, r_s = ?0.846; P < 0.001) between total length of roundtail chub Gila robusta and number of Asian fish tapeworms. A significant, but weaker negative correlation existed between weight of fish and number of tapeworms (r_s = ?0.687; P < 0.001). In addition, infected fish were significantly shorter (P = 0.0241) than uninfected fish. Infection by Asian fish tapeworm may slow growth, increase susceptibility to infestation, and increase predation on roundtail chub and possibly other native cyprinids.     

Effectiveness of Praziquantel Bath Treatments against Bothriocephalus acheilognathi in Grass Carp

Abstract

Many states ban the importation of fish infected with the Asian tapeworm Bothriocephalus acheilognathi. Treatment with an effective tapeworm parasiticide prior to shipment would allow fish to be imported that might otherwise be rejected. In this study, extended praziquantel bath treatments of infected grass carp Ctenopharyngodon idella were tested to determine their efficacy against Asian tapeworms. Preliminary praziquantel treatments of 0.7 mg/L or more for an exposure period of 24 h at grass carp densities of 69 g/L were effective in eliminating all tapeworms from 22-g fish. When the treatment duration was lowered to 12 h, a praziquantel concentration of 2.8 mg/L was required for effective treatment. In replicated studies, significantly reduced tapeworm numbers (0–5 tapeworms per treated fish compared with 30+ tapeworms per control fish) were observed following 24-h exposures to praziquantel at 0.5, 0.7, 1.0, and 1.5 mg/ L. Tapeworm elimination occurred only at the maximum concentration of 1.5 mg/L when 88-g grass carp were stocked at a density of approximately 6 g/L. When fish density was raised to 60 g/L, the 1.5-mg/L treatment did not eliminate all tapeworms: 4 of 30 fish contained a single tapeworm.     

First Record of Bothriocephalus acheilognathi in the Rio Grande with Comparative Analysis of ITS2 and V4-18S rRNA Gene Sequences

Abstract

Bothriocephalus acheilognathi is an introduced tapeworm in North America often reported as a serious ecological threat to native fishes. In this paper, we report the first record of B. acheilognathi in the Big Bend region of the Rio Grande in Texas (known as the Río Bravo del Norte in Mexico). Identification of B. acheilognathi was confirmed by morphologic and genetic techniques (sequences of ITS2 and V4-18S rRNA genes). Its prevalence was 27% and its intensity ranged from 1 to 5 individuals in a January 2006 collection of 115 red shiners Cyprinella lutrensis. In addition, it was found in the Tamaulipas shiner Notropis braytoni, a Rio Grande endemic and a new host record. The occurrence of B. acheilognathi might have negative ecological impacts on endemic fishes in the Rio Grande. Several of the fishes that could serve as definitive hosts are of conservation concern. Its occurrence also might affect the success of reintroducing the Rio Grande silvery minnow Hybognathus amarus, which is federally listed as endangered, in this portion of the Rio Grande.     

First record of Bothriocephalus acheilognathi in the Rio Grande with comparative analysis of ITS2 and V4-18S rRNA gene sequences

Bothriocephalus acheilognathi is an introduced tapeworm in North America often reported as a serious ecological threat to native fishes. In this paper, we report the first record of B. acheilognathi in the Big Bend region of the Rio Grande in Texas (known as the Río Bravo del Norte in Mexico). Identification of B. acheilognathi was confirmed by morphologic and genetic techniques (sequences of ITS2 and V4-18S rRNA genes). Its prevalence was 27% and its intensity ranged from 1 to 5 individuals in a January 2006 collection of 115 red shiners Cyprinella lutrensis. In addition, it was found in the Tamaulipas shiner Notropis braytoni, a Rio Grande endemic and a new host record. The occurrence of B. acheilognathi might have negative ecological impacts on endemic fishes in the Rio Grande. Several of the fishes that could serve as definitive hosts are of conservation concern. Its occurrence also might affect the success of reintroducing the Rio Grande silvery minnow Hybognathus amarus, which is federally listed as endangered, in this portion of the Rio Grande.     

美国的牛奶定价方法

直到19世纪末,像大多数液体一样,牛奶是依据体积来简单定价的。但是,每一位牛奶生产者都知道牛奶离统一标准还差很远。因为饲养管理、奶牛个体、泌乳期、季节和其他未知因素导致了牛奶成分的不同,例如,一些牛奶含有比其他牛奶多两倍的脂肪。1890年Babcock检测发展起来,这是一种简单、快速、准确地检测乳脂肪成分的方法。它可以直接确定从牛奶中提炼出奶油或者黄油的量,并且可以精确地预测奶酪的量。Babcock检测方法改革了牛奶的定价,并很快被购买牛奶的工厂采用。随着商业性乳产业的发展,牛奶量的检测从体积基准转向重量,因为精确地确定重…     

First glimpse into the origin and spread of the Asian longhorned tick,Haemaphysalis longicornis,in the United States

Established populations of Asian longhorned ticks (ALT), Haemaphysalis longicornis, were first identified in the United States (US) in 2017 by sequencing the mitochondrial cytochrome c oxidase subunit I (cox1) ‘barcoding’ locus followed by morphological confirmation. Subsequent investigations detected ALT infestations in 12, mostly eastern, US states. To gain information on the origin and spread of US ALT, we (1) sequenced cox1 from ALT populations across 9 US states and (2) obtained cox1 sequences from potential source populations [China, Japan and Republic of Korea (ROK) as well as Australia, New Zealand and the Kingdom of Tonga (KOT)] both by sequencing and by downloading publicly available sequences in NCBI GenBank. Additionally, we conducted epidemiological investigations of properties near its initial detection locale in Hunterdon County, NJ, as well as a broader risk analysis for importation of ectoparasites into the area. In eastern Asian populations (China/Japan/ROK), we detected 35 cox1 haplotypes that neatly clustered into two clades with known bisexual versus parthenogenetic phenotypes. In Australia/New Zealand/KOT, we detected 10 cox1 haplotypes all falling within the parthenogenetic cluster. In the United States, we detected three differentially distributed cox1 haplotypes from the parthenogenetic cluster, supporting phenotypic evidence that US ALT are parthenogenetic. While none of the source populations examined had all three US cox1 haplotypes, a phylogeographic network analysis supports a northeast Asian source for the US populations. Within the United States, epidemiological investigations indicate ALT can be moved long distances by human transport of animals, such as horses and dogs, with smaller scale movements on wildlife. These results have relevant implications for efforts aimed at minimizing the spread of ALT in the United States and preventing additional exotic tick introductions.     

The llama industry in the United States

This chapter provides an overview of the llama in the United States. It covers the animal and its history, the people who own llamas, and the business that is developing around them and describes the industry's needs from the veterinary profession in terms of health care.     

Reportable animal diseases in the United States

Timely reporting of animal diseases is fundamental to the detection of emerging threats, rapid and effective outbreak response, and ultimately the health of both animals and humans. In the United States, each state has the authority to regulate reporting of diseases. While past research has reviewed reportable human diseases, the research on reportable animal diseases has assessed only veterinarian knowledge and understanding of law rather than identifying the actual statutes and regulation that exists. Therefore, this article reviewed the statutes, regulations, and online reportable animal disease lists from the 50 states and District of Columbia to describe the legal landscape of animal disease reporting. The findings suggest wide variation in state animal disease reporting requirements. Three hundred and forty distinct diseases, agents, and categories were identified, with only 15 diseases being listed by 40 or more states. States typically require reporting of animal diseases within 48 h. Substantial consideration needs to be given to the implications of these variations for rapid and effective animal and zoonotic disease detection and reporting in the United States, particularly in light of One Health initiatives and international obligations.     

Dermatophytosis in show lambs in the United States

A dermatophytosis, called 'club lamb fungus' by owners, has been affecting show lambs during the lamb show season. Thirty-one families of 108 responding to a questionnaire reported at least one case of dermatophytosis, and 15 of those 31 families reported children or owners involved in showing these lambs developing skin lesions consistent with dermatophytosis. In lambs, gross lesions typical of ovine derma-tophytosis were located on all parts of the body, and consisted of circular areas of matted wool, crusts and discoloration. Lesions appeared either at a single site or were distributed randomly, affecting head, body and extremities. Direct microscopic examination of wool revealed ectothrix, endothrix, and combined endothrix and ectothrix infections. Microsporum gypseum was the only dermatophyte cultured from wool samples collected from affected lambs; however, the presence of endothrix spores suggests that other species may be involved. Arthrospores and fungal hyphae typical of dermatophytes were present in histological sections.     

Rabies surveillance in the United States during 1998

During 1998, 49 states, the District of Columbia, and Puerto Rico reported 7,961 cases of rabies in nonhuman animals and 1 case in a human being to the Centers for Disease Control and Prevention, a decrease of 6.5% from 8,509 cases in nonhuman animals and 4 cases in human beings reported in 1997. More than 92% (7,358 cases) were in wild animals, whereas > 7.5% (603 cases) were in domestic species (compared with 93% in wild animals and 7% in domestic species in 1997). Decreases were evident in all of the major contributing species groups, with the exception of skunks and bats. The relative contributions of the major groups to the total reported for 1998 were reccoons (44.0%; 3,502 cases), skunks (28.5%; 2,272), bats (12.5%; 992), foxes (5.5%; 435), cats (3.5%; 282), cattle (1.5%; 116), and dogs (11.5%; 113). No further discernable westward extension of the epizootic of rabies in raccoons in Ohio was reported. Twelve of the 19 states enzootic for the raccoon variant of the rabies virus and the District of Columbia reported decreased numbers of cases of rabies during 1998, compared with 13 states and the District of Columbia that reported increases during 1997. Three states, Rhode Island (143.2%), Massachusetts (77.2%), and New Hampshire (69.4%), reported increases of > 50% during 1998, compared with totals reported for 1997. In Texas, the number of cases of rabies associated with enzootic canine variants of the rabies virus remained greatly diminished; however, overall totals of reported cases of rabies increased in Texas and 12 other states where skunks are the major terrestrial reservoir of rabies. At the national level, the total of 82 reported cases of rabies among horses and mules was greater than that reported for any year since 1981 (88 cases) and represented a 74.5% increase, compared with the total for 1997. The 992 cases of rabies reported in bats during 1998 were the greatest proportionate contribution by bats since 1990. Reported cases of rabies in cats (282), dogs (113), and cattle (116) decreased 6.0%, 10.3%, and 4.9%, respectively. One indigenously acquired case of rabies reported in a human being during 1998 was the result of infection with a rabies virus variant associated with silver-haired and eastern pipistrelle bats.     

Rabies surveillance in the United States during 1989

In 1989, 4,808 cases of rabies in animals other than human beings were reported to the Centers for Disease Control, 1.8% more (4,724 to 4,808) than in 1988. Eighty-eight percent (4,224/4,808) of those affected were wild animals and 12% (584/4,808) were domestic animals. Cases were reported from 49 states, the District of Columbia, and Puerto Rico; Hawaii remained rabies-free. Skunks (1,657) continued to be the most commonly reported rabid wild animal. For the second consecutive year, more cats (212) were reported to be infected with rabies virus than any other domestic species. Compared with their 1988 reports, 5 states reported increases of greater than 100% (Alaska, 109%; New Jersey, 233%; Ohio, 133%; Oklahoma, 168%; and Washington, 125%), and 5 states reported decreases of greater than 50% (Connecticut, 63%; Mississippi, 56%; Montana, 67%; Nevada, 55%; and West Virginia, 53%) in 1989.