Diarrhoea In Lambs Research Articles

Zoonotic Cryptosporidiosis from Petting Farms, England and Wales, 1992–2009

To the Editor: Visits to petting farms in England and Wales recently have increased in popularity. Petting farms are commercial operations at which visitors, mainly families and organized groups, are encouraged to have hands-on contact with animals. The ≈1,000 petting farms in the United Kingdom collectively receive >2 million visitors per year, with peak visitor times during school and public holidays. Commercial farms also may host farm visits on single days for group and school visits. The farm attraction business is a substantial part of the rural economy, generating >£12 million annually (1). During 1992–2009, a total of 55 outbreaks of infectious intestinal disease associated with petting farms in England and Wales was reported to the Health Protection Agency. Verocytotoxin-producing Escherichia coli O157 (VTEC O157) caused 30 (55%) of these outbreaks (244 persons were affected [range 2–93, mean 8 persons] and 84 were hospitalized); Salmonella enterica serovar Typhimurium definitive phage type 104 caused 2 (3%) of the outbreaks. A total of 23 (42%) petting farm outbreaks were caused by Cryptosporidium spp. (1,078 persons were affected [range 2–541, mean 45 persons] and 29 were hospitalized). We report on these cryptosporidiosis outbreaks as a reminder of the risk to petting farm visitors. Contributory factors reported in the cryptosporidiosis outbreaks included direct contact with preweaned lambs, calves, kids, or animal feces (e.g., diarrhea in lambs, a recognized risk factor for cryptosporidiosis; 11/23 [48%]) and inadequate hand washing facilities (7/23 [30%]). Of outbreaks in which hand washing facilities were inadequate, thumb sucking by children was also noted in 1; in another, alcohol-based hand gels and sanitizers, which are ineffective against Cryptosporidium spp., were used. Cryptosporidium spp. are coccidian parasites that infect a wide range of farm livestock, including cattle, sheep, goats, pigs, horses, and deer, but are mainly a veterinary problem in neonatal ruminants. C. parvum, for example, is a common agent in the etiology of the neonatal diarrhea syndrome of calves, lambs, and goat kids. Widespread asymptomatic carriage of this parasite exists in livestock in the United Kingdom (2). In humans, cryptosporidiosis occurs most commonly in children <5 years of age, can be life threatening in immunocompromised persons, and is caused predominantly by C. hominis and C. parvum parasites. Fecal–oral transmission can occur directly from animal to person and from person to person or indirectly through contaminated food or water (2). Typing of Cryptosporidium spp. has been undertaken by the UK Cryptosporidium Reference Unit since 1999. C. parvum was identified from human feces in 12 (75%) of the 16 petting farm outbreaks since 1999 (feces were not submitted for typing in 4). Additionally, Cryptosporidium spp. oocysts were detected and confirmed as C. parvum from suspected sources (lambs, calves) in 4 (33%) of these 12 outbreaks and linked by GP60 subtype to human cases in 3 outbreaks. Zoonotic risk factors in case–control studies of sporadic cryptosporidiosis cases in England and Wales also have identified an association between C. parvum infection and touching farm animals or visiting a farm (3). In petting farm outbreaks, Cryptosporidium spp. displayed a seasonal pattern, as did VTEC O157. Cryptosporidiosis outbreaks occurred more often in springtime (18 vs. 5; p = 0.0001) than did VTEC O157 outbreaks, which occurred more frequently during the summer (25 vs. 5; p<0.00001), especially in August (Figure). During spring 2010, two additional C. parvum outbreaks associated with contact with lambs at petting farms were reported in England. Control measures included restricting bottle feeding of lambs and enhancing the supervision of hand washing. The associations with outbreaks of cryptosporidiosis in spring and contact with young farm animals also has been reported in Scotland (4). Figure Outbreaks of cryptosporidiosis and verocytotoxin-producing Escherichia coli O157 linked to petting farms, England and Wales, 1992–2009. Despite the 2 separate seasonal peaks of infection, care should be exercised throughout the year. The importance of careful attention to hygiene and supervision of children visiting farms and the need for appropriate facilities, such as those for hand washing, are covered in the UK Health and Safety Executive standards; operators of petting farms are expected to meet these standards (5). These guidelines also apply to commercial farms hosting open days. A good practice reminder on managing the risks from VTEC O157 in a petting farm context was published by the Health Protection Agency, Health and Safety Executive, and the Local Government Regulation (6). Guidance on the control of VTEC O157 infections for farms open to public access applies equally to most gastrointestinal pathogens, including Cryptosporidium spp. The need for a sound approach to managing hygiene control measures at petting farms cannot be overemphasized.

Genetic analysis of the porcine group B rotavirus NSP2 gene from wild-type Brazilian strains

Group B rotaviruses (RV-B) were first identified in piglet feces, being later associated with diarrhea in humans, cattle, lambs, and rats. In human beings, the virus was only described in China, India, and Bangladesh, especially infecting adults. Only a few studies concerning molecular analysis of the RV-B NSP2 gene have been conducted, and porcine RV-B has not been characterized. In the present study, three porcine wild-type RV-B strains from piglet stool samples collected from Brazilian pig herds were used for analysis. PAGE results were inconclusive for those samples, but specific amplicons of the RV-B NSP2 gene (segment 8) were obtained in a semi-nested PCR assay. The three porcine RV-B strains showed the highest nucleotide identity with the human WH1 strain and the alignments with other published sequences resulted in three groups of strains divided according to host species. The group of human strains showed 92.4 to 99.7% nucleotide identity while the porcine strains of the Brazilian RV-B group showed 90.4 to 91.8% identity to each other. The identity of the Brazilian porcine RV-B strains with outer sequences consisting of group A and C rotaviruses was only 35.3 to 38.8%. A dendrogram was also constructed to group the strains into clusters according to host species: human, rat, and a distinct third cluster consisting exclusively of the Brazilian porcine RV-B strains. This is the first study of the porcine RV-B NSP2 gene that contributes to the partial characterization of this virus and demonstrates the relationship among RV-B strains from different host species.

The sheep industry in the Nordic countries

The sheep industry in the Nordic countries varies considerably, with numbers of breeding ewes reaching 57,000, 113,000, 220,000, 400,000 and 1,000,000 in Finland, Denmark, Sweden, Iceland and Norway, respectively. Average flock size varies from 12 ewes in Denmark to 255 ewes in Iceland. Main income is derived from lamb meat; wool and milk are of minor importance. Major animal welfare and health concerns relates to neonatal lamb losses, predation during summer pastures and parasitic diarrhoea in lambs. Contagious diseases are rare and control and eradication programs for scrapie and Lentivirus-infections are currently taking place.

The determination of a fecal D‐lactate threshold in neonatal ruminants with diarrhea

We have documented D‐lactic acidosis secondary to diarrhea in neonatal calves and lambs. The acidosis only appears after sufficiently high levels of D‐lactate are produced by microbial action in the gut. Measurements of serum and fecal lactate led to a determination of a fecal threshold for D‐lactate systemic absorption from the gut in neonatal ruminants. Jugular blood and feces were collected from 27 diarrheic and 4 healthy lambs, and 19 diarrheic and 4 healthy calves. Blood was analysed for pH, bicarbonate concentration (HCO3−), base excess (BE), hemoglobin (Hb), Na+, K+, Ca2+, Cl−, anion gap, and glucose. Serum, feces, and urine were analyzed for lactate enantiomers. A range of mild to severe diarrhea, as well as metabolic acidosis was observed with a corresponding wide range of D‐lactate concentrations in both serum (&lt; 0.05‐24.0 mmol/L) and feces (&lt; 0.05‐31.0 mmol/L). The fecal D‐lactate threshold was determined statistically using biphasic (break‐point) regression analysis (serum vs fecal D‐lactate). This fecal threshold concentration for absorption of D‐lactate was 10.2 and 8.8 mmol/L in lambs (n=31) and calves (n=23), respectively. These similar values in different species support a lumen D‐lactate threshold (~10 mmol/L) for monocarboxylic (i.e. lactate) transporters and uptake into the mucosal cells and then blood circulation. Therefore, controlling the amount of D‐lactate produced by gut bacteria, and hence lowering levels below threshold, may be key in preventing the metabolic acidosis common in enteritis.

Distribution of Cryptosporidium species in sheep in the UK

There have been few studies of the distribution of Cryptosporidium species and genotypes in sheep, and the anthropozoonotic potential has been questioned since one of the major human pathogens, Cryptosporidium parvum, is not always found. To investigate the situation in the UK we undertook three studies: a reactive sampling programme of flocks identified as exposures for human cases of cryptosporidiosis; investigation of neonatal cryptosporidiosis in lambs; and a screening programme of lambs at an open farm. C. parvum was the only species found in neonatal lambs with cryptosporidiosis and predominated in flocks sampled reactively to a human case of cryptosporidiosis. C. bovis was also found in the latter study but at a lower frequency than C. parvum. C. bovis and the cervine genotype were found in the orphan lambs under the screening programme. The results of these studies show that C. parvum is important in neonatal lamb diarrhoea and is widespread in sheep flocks in the UK, but that other Cryptosporidium species and genotypes are also present. Sheep, and young lambs in particular, must still be considered as a source of C. parvum infection for humans.

Prevalence and virulence gene profiles of Shiga toxin-producing Escherichia coli and enteropathogenic Escherichia coli from diarrhoeic and healthy lambs in India

This communication describes the prevalence and virulence attributes of Shiga toxin-producing Escherichia coli (STEC) and enteropathogenic E. coli (EPEC) isolates in lambs with and without diarrhoea in Kashmir, India. One hundred twenty and 164 E. coli isolates belonging to 56 different ‘O’ serogroups were isolated from 101 diarrhoeic and 135 healthy lambs, respectively. All the 284 isolates were screened for presence of stx 1 , stx 2 , eae and ehxA genes using multiplex polymerase chain reaction (m-PCR). Forty four (36.67%) isolates from lambs with diarrhoea carried at least one virulence gene studied. Twenty one (17.5%) and 15 (12.5%) isolates from diarrhoeic lambs were STEC and EPEC, respectively. Thirty (18.3%) isolates from healthy lambs possessed at least one virulence gene studied. Fourteen (8.53%) and 16 (9.75%) isolates from healthy lambs were detected as STEC and EPEC, respectively. Sixteen (45.71%) of 35 STEC isolates from both diarrhoeic and healthy lambs, carried both stx 1 and stx 2 genes, 15 (42.85%) had stx 1 alone and four (11.42%) had stx 2 gene alone. Statistically the difference between prevalence of STEC in diarrhoeic and healthy lambs was significant but that of EPEC was insignificant. One (2.85%) and 28 (80%) of STEC isolates possessed eae and ehxA genes, respectively. The high percentage of STEC and EPEC prevalent in diarrhoeic and healthy lambs may serve as source of infection to humans. STEC seem to be associated with diarrhoea in lambs.

Effect of halofuginone lactate on treatment and prevention of lamb cryptosporidiosis: an extensive field trial

This study aimed to investigate the effects of halofuginone lactate (100 mug/kg BW) on treatment and prevention of cryptosporidiosis in lambs. It consisted of three field trials. The first trial was designed to assess the efficacy of halofuginone in treating lamb diarrhoea caused by cryptosporidiosis, and in preventing the disease, using two schemes; halofuginone given for seven and for three consecutive days respectively. Halofuginone was effective in the treatment of diarrhoea caused by cryptosporidiosis (P < 0.01). In addition, halofuginone administered as a 7-day treatment was significantly (P < 0.05) more effective than a 3-day treatment in preventing diarrhoea in the infected flocks. The second trial was designed to evaluate the preventive effect of halofuginone, which was administered for 7 days in lambs infected with cryptosporidiosis, on diarrhoea incidence, oocyst shedding and body weight gain. Halofuginone significantly (P < 0.01) reduced the diarrhoea incidence, the time of oocyst shedding and the mean intensity of shedding, but did not affect body weight gain. The third trial was designed to examine the ability of halofuginone to reduce the death rate in flocks with cryptosporidiosis. Halofuginone treatment was effective in preventing and in reducing the death rate of cryptosporidiosis in these flocks.

Observations and immunohistochemical detection of Coronavirus, Cryptosporidium parvum and Giardia intestinalis in neonatal diarrhoea in lambs and kids

In this study, clinical, parasitological, macroscopical, histopathological and immunohistochemical examinations were performed on 19 kids and 11 lambs (30 animals) with neonatal diarrhoea to detect the presence of Coronavirus, Cryptosporidium parvum and Giardia intestinalis. Clinically, severe dehydration, yellowish-green to brown coloured diarrhoea and death were observed. Mortality rates were 10-30% in the examined flocks. The most common agent was C. parvum diagnosed in 20 animals as a single causative agent, whereas G. intestinalis was found in 5 of 30 animals. These two protozoa were detected together in 4 animals upon faeces examination. Fifteen of 24 cases of C. parvum and 3 of 11 cases of G. intestinalis were also confirmed histopathologically. Following immunohistochemical examination, all cryptosporidiosis cases were confirmed by positive immunostaining of intestinal sections. Two additional Giardiosis cases with negative results upon parasitological and histopathological examinations were diagnosed by means of immunohistochemical examination. Coronavirus was detected immunohistochemically in one kid with neonatal enteritis. Following diagnosis, herds were treated with Trimethoprim + Sulfodoxine and multivitamin complexes. Intravenous and intramuscular administrations of these drugs were effective for both treatment and prevention of neonatal diarrhoea in lambs and kids.

Evaluation of some etiological factors predisposing to diarrhoea in lambs in “La Serena” (Southwest Spain)

This study compares some etiological factors involved in the naturally occurrence of lamb scours in 18 Merino sheep farms randomly selected in the area of “La Serena” (Southwest Spain). A lack of influence of some variables (flock size, type of facilities, type of breeding, lambing percentage, isolation of Campylobacter jejuni, Rotavirus spp., Coronavirus spp. and Salmonella spp.) on lamb mortality rate was detected. The opposite was true for cleaning of the lambing areas, organization of lambing periods, accumulation of lambs in the pens, high content of fat, protein and lactose in milk and low serum gamma globulin and total protein in lambs and ewes. Cryptosporidium spp. and Escherichia coli isolation showed a trend to be linked to the presence of diarrhoea. A positive correlation was found between serum total protein in ewes and serum gamma globulin in lambs. Thus, the measure of serum total protein in ewes before lambing would be a valuable indicator of the risk of lamb scouring and it would be useful to establish an adequate programme to prevent this condition in the farms of this geographical area.

Differential diagnosis of diarrhoea in lambs

WHILE the consistency of healthy sheep faeces varies from firm pellets to soft paste, depending on the dry matter and fibre content of the diet, the observation of fluid faeces...

Evidence of rotavirus associated with neonatal lamb diarrhoea in India.

Evidence of rotavirus associated with neonatal lamb diarrhoea in India.

Isolation and characterization of Shiga toxin-producing Escherichia coli (STEC) and enteropathogenic Escherichia coli (EPEC) from calves and lambs with diarrhoea in India.

To determine the prevalence and molecular characteristics of Shiga toxin-producing Escherichia coli (STEC) and enteropathogenic E. coli (EPEC) in calves and lambs with diarrhoea in India. Faecal samples originating from 391 calves and 101 lambs which had diarrhoea were screened for presence of E. coli. A total number of 309 (249 bovine and 60 ovine) E. coli strains were isolated. A total of 113 bovine and 15 ovine strains were subjected to multiplex polymerase chain reaction (m-PCR) for detection of stx1, stx2, eaeA and EHEC hlyA genes. STEC and EPEC belonging to different serogpoups were detected in 9.73% of calves studied. Six per cent and 26.66% of lambs studied were carrying STEC and EPEC, respectively. Majority of the STEC serogroups isolated in this study did not belong to those which have been identified earlier to be associated mainly with diarrhoea and enteritis in cattle and sheep outside India. The most frequent serogroup among bovine and ovine EPEC was O26 (40%). One of the most important STEC serogroup O157, known for certain life-threatening infections in humans, was isolated from both bovine and ovine faecal samples. A high percentage of STEC and EPEC belonging to different serogroups are prevalent in calves and lambs with diarrhoea in India and could be the cause of disease in them. The study reports, for the first time, the isolation and characterization of STEC and EPEC serogroups associated with diarrhoea in calves and lambs in India. Many STEC and EPEC strains belonged to serogoups known for certain life-threatening diseases in humans.

Prevalence and characterization of Vero cytotoxin-producing Escherichia coli isolated from diarrhoeic and healthy sheep and goats.

Faecal samples from 146 diarrhoeic lambs and goat kids, and from 511 healthy sheep and goats were screened for the presence of Vero cytotoxin-producing Escherichia coli (VTEC). In healthy sheep and goats, VTEC were isolated in 24.4 and 16.2% of the animals, respectively. Moreover, VTEC were detected in 3.1 and 5.9% of the diarrhoeic lambs and goat kids, respectively. These data suggest that VTEC seems not to be associated with diarrhoea in lambs and goat kids. Only four VTEC strains were eae-positive. The absence of the eae gene in most of these VTEC strains could indicate that these strains are less virulent for humans that the classical eae-positive enterohaemorrhagic E. coli types. However, almost half (42.9%) and 12.2% of VTEC strains isolated from healthy sheep and goats, respectively, belonged to serotypes associated with severe diseases in humans.

Nutritive value and aversion of honey mesquite leaves to sheep

Honey mesquite (Prosopis glandulosa Torr.) is an invasive native plant that is abundant in Mexico and the Southwestern United States. We initiated 2 studies to determine if: 1) mesquite could provide valuable forage for domestic herbivores; and 2) if mesquite causes conditioned flavor aversions in ruminants. An in vivo digestion trial was completed with 15 lambs assigned to diets of 0, 5, 10, 15, or 20% dried mesquite leaves mixed with alfalfa hay to measure effects of mesquite on intake and digestion. Proportions of mesquite leaves &gt;5% of the diet negatively affected dry matter (DM) intake, nitrogen (N) balance, energy balance and weight gain. Mesquite intake was highest at the 5% level averaging 1.81 g kg-1 body weight (BW), mesquite intake of the other mesquite-containing diets averaged 0.78 g kg-1 BW. Apparent digestibility was not affected by the level of mesquite in the diet. An in situ digestion trial did however, reveal that pure alfalfa was more digestible than mesquite leaves. A conditioned flavor aversion (CFA) trial tested the effect of post-ingestive feedback from mesquite on the intake of a novel food (rye). Lambs were offered rye and then ground mesquite was infused into their rumens by esophageal tube. Twenty one lambs were assigned to 3 dosing treatments: 0 (control), 3.0 (low), or 4.5 (high) g of mesquite per kg BW. Two days after dosing, lambs that received mesquite infusions ate less rye than controls indicating the formation of a CFA. The aversion to rye persisted for at least 2 days. The high dose of mesquite also decreased intake of the alfalfa basal ration for at least 3 days and resulted in persistent diarrhea in lambs. Chemical analysis of mesquite leaves revealed similar nutritive quality (crude protein, gross energy, and fiber) as mature alfalfa. However, to exploit the forage value of mesquite, the allelochemicals that cause flavor aversions and other negative digestive consequences need to be identified and overcome.

Nutritive Value and Aversion of Honey Mesquite Leaves to Sheep

Honey mesquite (Prosopis glandulosa Torr.) is an invasive native plant that is abundant in Mexico and the Southwestern United States. We initiated 2 studies to determine if: 1) mesquite could provide valuable forage for domestic herbivores; and 2) if mesquite causes conditioned flavor aversions in ruminants. An in vivo digestion trial was completed with 15 lambs assigned to diets of 0, 5, 10, 15, or 20% dried mesquite leaves mixed with alfalfa hay to measure effects of mesquite on intake and digestion. Proportions of mesquite leaves > 5% of the diet negatively affected dry matter (DM) intake, nitrogen (N) balance, energy balance and weight gain. Mesquite intake was highest at the 5% level averaging 1.81 g kg-1 body weight (BW), mesquite intake of the other mesquite-containing diets averaged 0.78 g kg-1 BW. Apparent digestibility was not affected by the level of mesquite in the diet. An in situ digestion trial did however, reveal that pure alfalfa was more digestible than mesquite leaves. A conditioned flavor aversion (CFA) trial tested the effect of post-ingestive feedback from mesquite on the intake of a novel food (rye). Lambs were offered rye and then ground mesquite was infused into their rumens by esophageal tube. Twenty one lambs were assigned to 3 dosing treatments: 0 (control), 3.0 (low), or 4.5 (high) g of mesquite per kg BW. Two days after dosing, lambs that received mesquite infusions ate less rye than controls indicating the formation of a CFA. The aversion to rye persisted for at least 2 days. The high dose of mesquite also decreased intake of the alfalfa basal ration for at least 3 days and resulted in persistent diarrhea in lambs. Chemical analysis of mesquite leaves revealed similar nutritive quality (crude protein, gross energy, and fiber) as mature alfalfa. However, to exploit the forage value of mesquite, the allelochemicals that cause flavor aversions and other negative digestive consequences need to be identified and overcome. DOI:10.2458/azu_jrm_v54i1_baptista

A multi-level model of data with repeated measures of the effect of lamb diarrhoea on weight

Over a 1-year period, data were collected from three flocks of sheep. A total of 213 lambs were examined routinely from birth to 32 kg (2178 examinations in total). Diarrhoea was seen in lambs of all ages but did not appear to make them systemically ill. The effect of diarrhoea on lamb weight was investigated using MLn, a multi-level modeling program. The data were set at three hierarchical levels: level one, the repeated examinations on each lamb; level two, the lamb; and level three, the litter. Age, the quadratic of age, litter size, sex and farm of origin, all had significant effect on the weight of the lambs. There was also significant random variation in examinations within lambs, between individual lambs and between litters of lambs. There was a reduction in absolute weight of lambs for each week until four weeks after an episode of diarrhoea.

The Molecular Basis for the Absence ofN-Glycolylneuraminic Acid in Humans

N-Glycolylneuraminic acid (NeuGc) is abundantly expressed in most mammals, but it is not detectable in humans. The expression of NeuGc is controlled by cytidine monophospho-N-acetylneuraminic acid (CMP-NeuAc) hydroxylase activity. We previously cloned a cDNA for mouse CMP-NeuAc hydroxylase and found that the human genome contains a homologue. We report here the molecular basis for the absence of NeuGc in humans. We cloned a cDNA for human CMP-NeuAc hydroxylase from a HeLa cell cDNA library. The cDNA encodes a 486-amino acid protein, and its deduced amino acid sequence lacks a domain corresponding to the N-terminal 104 amino acids of the mouse CMP-NeuAc hydroxylase protein, although the human protein is highly identical (93%) to the rest of the mouse hydroxylase protein. The N-terminal truncation of the human hydroxylase is caused by deletion of a 92-base pair-long exon in human genomic DNA. The human hydroxylase expressed in COS-7 cells exhibited no enzymatic activity, and a mouse hydroxylase mutant, which lacks the N-terminal domain, was also inactive. A chimera composed of the human hydroxylase and the N-terminal domain of the mouse hydroxylase displayed the enzyme activity. These results indicate that the human homologue of CMP-NeuAc hydroxylase is inactive because it lacks an N-terminal domain that is essential for enzyme activity. The absence of NeuGc in human glycoconjugates is due to a partial deletion in the gene that encodes CMP-NeuAc hydroxylase.

Role of enteric pathogens in the aetiology of neonatal diarrhoea in lambs and goat kids in Spain.

Faeces samples from diarrhoeic and non-diarrhoeic lambs and goat kids aged 1-45 days were examined for enteric pathogens. Cryptosporidium parvum was detected in both diarrhoeic lambs (45%) and goat kids (42%) but not in non-diarrhoeic animals. F5+ (K99+) and/or F41+ Escherichia coli strains were isolated from 26% and 22% of the diarrhoeic lambs and goat kids, respectively, although these strains, which did not produce enterotoxins ST I or LT I, were found with similar frequencies in non-diarrhoeic animals. A F5-F41-ST I+ E. coli strain was isolated from a diarrhoeic lamb (0.6%). Verotoxigenic E. coli was isolated from both diarrhoeic and non-diarrhoeic lambs (4.1% and 8.2%, respectively) and there was no association between infection and diarrhoea. The prevalence of group A rotavirus infection in diarrhoeic lambs was very low (2.1%). Groups A and B rotaviruses were detected in three (8.1%) and five (13.5%) diarrhoeic goat kids from two single outbreaks. Group C rotaviruses were detected in four non-diarrhoeic goat kids. An association of diarrhoea and infection was demonstrated only for group B rotavirus. Clostridium perfringens was isolated from 10.8% of the diarrhoeic goat kids but not from non-diarrhoeic goat kids or lambs. Salmonella arizonae was isolated from a diarrhoeic goat kid (2.7%) and the clinical characteristics of the outbreaks where these two latter enteropathogens were found different from the rest. Picobirnaviruses were detected in a diarrhoeic lamb. No coronaviruses were detected using a bovine coronavirus ELISA. No evidence was found of synergistic effect between the agents studied. Enteric pathogens were not found in four (8.7%) and three (20%) outbreaks of diarrhoea in lambs and goat kids, respectively.

Rotaviruses associated with neonatal lamb diarrhea in two Wyoming shed-lambing operations.

White scours was first recognized in 1927 as an important cause of newborn lamb loss in shed-lambing operations in the western United States. 4 This disease was thought to be caused by bacteria, but no specific pathogen was identified. Lamb scours remains an important disease in the United States, 3 and several bacteria are now considered etiologic agents, including Bacteroides fragilis 5 and K99 piliated, enteropathogenic Escherichia coli. 11 Moreover, the coccidian parasite Cryptosporidium also has been associated with diarrhea in young lambs. 1 Viruses associated with neonatal lamb diarrhea were not reported in the United States until very recently. 7 In this instance, group B rotavirus was detected during an outbreak of diarrhea in newborn confinement-reared lambs in Ohio. Each spring during the past 5 years, several large shedlambing operations in eastern Wyoming have experienced severe outbreaks of neonatal diarrhea associated with high morbidity and mortality. The purpose of this study was to determine if any potentially pathogenic enteric viruses could be detected by negative-stain electron microscopic (EM) examination of specimens collected from neonatal diarrheic lambs in 2 of these operations. In early April 1994, specimens were collected from affected lambs in 2 eastern Wyoming shed-lambing operations situated about 40 km apart. Ranch A routinely shed-lambs over 1,300 lambs within a 30-day period commencing in early March. In some years the first scouring lambs were observed during the first week of shed-lambing, whereas in other years they occurred later. Clinical signs were observed when the lambs were 12-16 hours old and consisted of frothy salivation, inappetence, and scours. Some affected lambs died within 4-5 hours following the onset of signs; surviving lambs, however, often gained weight slowly and were prone to other infectious diseases. Once the outbreak was under way, morbidity approached 100%, and about 10% of the affected lambs died. Ranch B routinely shed-lambs between 3,000 and 5,000 lambs within a 30-day period starting in early March. Affected lambs were not ordinarily observed during the first week, but sometime afterward a lamb would become ill while still in the lambing pen. Within 4-5 days after the first case, many lambs were affected, and thereafter the majority of the lambs kept in the shed area became ill. Initial clinical signs

Actinobacillus suis-like organisms associated with septicemia in neonatal calves.

mune electron microscopy and genome electropherotyping techniques for detection of turkey rotaviruses and rotaviruslike viruses in intestinal contents. J Clin Microbiol 23:695-699. 11. Theil KW, Saif LJ, Moorhead PD, Whitmoyer RD: 1985, Porcine rotavirus-like virus (group B rotavirus): characterization and pathogenicity for gnotobiotic pigs. J Clin Microbiol 21:340345. Ward ACS, Bulgin MS, Anderson BC: 1991, Early detection of K99 piliated Escherichia coli in field outbreaks of lamb diarrhea. Agri-Practice 12(5):40-45.