The Effects of Artificially Dosed Adult Rumen Contents on Abomasum Transcriptome and Associated Microbial Community Structure in Calves

This study aimed to investigate the changes in abomasum transcriptome and the associated microbial community structure in young calves with artificially dosed, adult rumen contents. Eight young bull calves were randomly dosed with freshly extracted rumen contents from an adult cow (high efficiency (HE), n = 4), or sterilized rumen content (Con, n = 4). The dosing was administered within 3 days of birth, then at 2, 4, and 6 weeks following the initial dosing. Abomasum tissues were collected immediately after sacrifice at 8 weeks of age. Five genera (Tannerella, Desulfovibrio, Deinococcus, Leptotrichia, and Eubacterium; p < 0.05) showed significant difference in abundance between the treatments. A total of 975 differentially expressed genes were identified (p < 0.05, fold-change > 1.5, mean read-counts > 5). Pathway analysis indicated that up-regulated genes were involved in immune system process and defense response to virus, while the down-regulated genes involved in ion transport, ATP biosynthetic process, and mitochondrial electron transport. Positive correlation (r > 0.7, p < 0.05) was observed between TRPM4 gene and Desulfovibrio, which was significantly higher in the HE group. TRPM4 had a reported role in the immune system process. In conclusion, the dosing of adult rumen contents to calves can alter not only the composition of active microorganisms in the abomasum but also the molecular mechanisms in the abomasum tissue, including reduced protease secretion and decreased hydrochloric acid secretion.

Can the foregut nematode Haemonchus contortus and medicinal plants influence the fecal microbial community of the experimentally infected lambs?

The abomasal parasitic nematode Haemonchus contortus can influence the abomasal microbiome of the host. On the other hand, no information occurs on the influence of the parasite on the hindgut microbiome of the host. We evaluated the impact of Haemonchus contortus on the fecal microbial community of the experimentally infected lambs treated with a mixture of medicinal herbs to ameliorate the haemonchosis. Twenty-four female lambs were divided into four groups: infected animals (Inf), infected animals supplemented with a blend of medicinal herbs (Inf+Herb), uninfected control animals (Control), and uninfected animals supplemented with medicinal herbs (C+Herb). Inf and Inf+Herb lambs were infected orally with approximately 5000 L3 larvae of a strain of H. contortus susceptible to anthelmintics (MHco1). Herb blend (Herbmix) consisted of dry medicinal plants of Althaea officinalis, Petasites hybridus, Inula helenium, Malva sylvestris, Chamomilla recutita, Plantago lanceolata, Rosmarinus officinalis, Solidago virgaurea, Fumaria officinalis, Hyssopus officinalis, Melisa officinalis, Foeniculum vulgare, and Artemisia absinthium. Each animal was fed meadow hay and a commercial concentrate (600 + 350 g DM/d). Inf+Herb and C+Herb lambs were fed Herbmix (100 g DM/d and animal). Treatment lasted for 50 days. The fecal microbial fermentation parameters (short-chain fatty acids, ammonia, and pH) were evaluated at intervals of 0, 20, 32, and 50 days. The fecal eubacterial populations were evaluated by denaturing gradient gel electrophoresis (DGGE) at day 32 when H. contortus infection was the highest. No substantial effects of the H. contortus infection and the herbal treatment on fecal microbial fermentation parameters and fecal eubacterial populations were observed. Evaluation of DGGE patterns by Principal component analysis pointed to the tendency to branch the C+Herb group from the other experimental groups on Day 32. The results indicate that hindgut microbial activity was not disturbed by H. contortus infection and herbal treatment.

Microbial diversity in the rumen, reticulum, omasum, and abomasum of yak on a rapid fattening regime in an agro-pastoral transition zone

The ruminant digestive system harbors a complex gut microbiome, which is poorly understood in the case of the four stomach compartments of yak. High-throughput sequencing and quantitative PCR were used to analyse microbial communities in the rumen, reticulum, omasum, and abomasum of six domesticated yak. The diversity of prokaryotes was higher in reticulum and omasum than in rumen and abomasum. Bacteroidetes predominated in the four stomach compartments, with abundance gradually decreasing in the trend rumen > reticulum > omasum > abomasum. Microorganism composition was different among the four compartments, all of which contained high levels of bacteria, methanogens, protozoa and anaerobic fungi. Some prokaryotic genera were associated with volatile fatty acids and pH. This study provides the first insights into the microorganism composition of four stomach compartments in yak, and may provide a foundation for future studies in this area.

[Nasal, pulmonary, and abomasal aspergillosis (Aspergillus fumigatus) in a calf]

This study presents a case of nasal aspergillosis in a 17-days old calf (German Fleckvieh): it had been admitted moribund to the Clinic for Ruminants of the University of Munich, and died after a short time. Pathologically, the calf was diagnosed with purulent-necrotizing rhinitis, necrotizing pneumonia, and diphtheroid-necrotizing abomasitis. Histologically, fungal elements were found in all the localizations mentioned before, and mycologically, Aspergillus fumigatus was cultured from nasal cavity. Pathogenesis is discussed.

Characteristics of fluid composition of left displaced abomasum in beef cattle fed high-starch diets

To clarify the pathophysiology of left displaced abomasum (LDA), beef cattle fed high-starch diets were examined. The abomasal pH in beef cattle with LDA was lower than that in non-LDA reference animals (data from beef cattle at an abattoir), suggesting that it facilitated acidity. Bacteriological examinations of the abomasal fluid in cattle with LDA revealed the presence of Pseudomonas spp., Clostridium spp. and Candida spp., presumably reflecting the accelerated influx of ruminal fluid into the abomasum. Biochemical analyses of serum revealed that LDA cattle had higher lactic acid and lower vitamin A and E levels than non-LDA reference animals. These results indicate that beef cattle with LDA may suffer from vitamin A and E deficiencies due to maldigestion of starch and the high acidity of abomasal fluid.

Clostridial abomasal disease in Connecticut dairy calves

Over 2 years, 24 dairy calves died of emphysematous abomasitis and abomasal bloat. Anaerobic cultures of necrotic abomasal mucosa yielded Clostridium perfringens from 10 of 15 calves. Sarcina were observed in 17 of 22 examined histologically. A change in the antibiotic regimen for newborns and improved sanitizing of feeding utensils eliminated further losses.

Rennet Paste from Lambs Fed a Milk Substitute Supplemented with Lactobacillus acidophilus: Effects on Lipolysis in Ovine Cheese

The present work was undertaken to evaluate the effects of Lactobacillus acidophilus supplementation of a milk substitute on the features of lamb rennet paste used for cheese making. Lipolysis in cheese manufactured with rennet paste from lambs receiving supplemented milk was also evaluated. Lambs were subjected to 3 different feeding regimens (mother suckling, MS; artificial rearing, AR; and artificial rearing with 7 log10 cfu/mL of Lb. acidophilus supplementation of the milk substitute, ARLb) and slaughtered at 20 and 40 d of age for each feeding treatment. Abomasa of the lambs were processed to rennet paste. Microbial loads, enzymatic activities (chymosin, pepsin, and lipases), and renneting characteristics of the lamb rennet paste were determined. Free fatty acids and conjugated linoleic acids were detected in cheese at 60 d of ripening. Addition of 7 log10 cfu/mL of Lb. acidophilus to the milk substitute was carried out successfully. Total recovery of viable cells was recorded in milk supplied daily to the lambs in the ARLb group. The ARLb rennet had greater amounts of lactobacilli than did the MS or AR rennet, irrespective of the slaughter age of the lambs, and the ARLb rennet had higher concentrations of lactococci when lambs were slaughtered at 40 d of age. Chymosin and lipase activities were also higher in ARLb rennet than in MS or AR rennet from lambs slaughtered at an older age. Milk supplementation of ARLb lambs resulted in improved coagulating ability of the rennet and enhanced cheese lipolysis after 60 d of ripening. A reduction of all free fatty acids was observed in all cheeses when passing from 20 to 40 d of slaughter of the lambs. Conjugated linoleic acids were more abundant in ARLb cheeses at both 20 and 40 d. Therefore, supplementation of the milk substitute with Lb. acidophilus improved the enzymatic features of rennet and the healthful and nutritional characteristics of it the ovine cheese. Moreover, the addition of lactobacilli to the milk substitute made it possible to increase the slaughter age of lambs without detrimental effects on rennet characteristics.

Abomasal bacteria produce an inhibitor of gastrin secretion in vitro

Previously, proliferating microflora transferred with abomasal nematodes, were suspected to be the source of the gastrin inhibitor in some parasite excretory/secretory products. Aerobic cultures in HBSS of abomasal fluid from uninfected sheep became inhibitory during the static growth phase, unless antibiotics were present. Basal gastrin secretion was reduced by up to 90%. Rumen fluid and incubates and medium in which Streptococcus bovis and ovine rumen Actinomycete spp. had been grown also contained the inhibitor. Unlike abomasal cultures, rumen fluid and incubates also reduced the measurement of gastrin standards. Rumen incubates were less potent after exposure to pH 2-3, suggesting that inactivation normally occurs in the unparasitised abomasum. Contaminating bacteria which generate the gastrin inhibitor in parasite ES products are probably rumen organisms which survive in the abomasum and proliferate during subsequent incubation. Significantly, rumen bacteria have been shown to be capable of affecting the secretory activity of the gastric mucosa.

Determination of the effect of single abomasal or jejunal inoculation of Clostridium perfringens type A in dairy cows

A randomized study was conducted to determine if inoculation of the abomasum or jejunum with Clostridium perfringens Type A would induce jejunal hemorrhage syndrome in healthy cows. Twelve adult nonlactating dairy cows were inoculated with 10 mL of pure culture broth of C. perfringens type A (beta2 toxin positive) into the abomasum (n = 6) or jejunum (n = 6). On day 6, the cows were euthanized and samples for culture were taken from the abomasum, jejunum, and feces. No cows developed clinical signs of jejunal hemorrhage syndrome during the course of the study. Five of 6 abomasal samples and 1 of 6 jejunal samples were positive for C. perfringens Type A (beta2 negative) prior to inoculation. Eight of 12 abomasal samples, 11 of 12 fecal samples, and 10 of 12 jejunal samples were positive for C. perfringens Type A (beta2 negative) after inoculation. Intraluminal inoculation of C. perfringens Type A alone at this dose and under these conditions did not induce clinical signs of jejunal hemorrhage syndrome in adult dairy cows. The multifactorial nature of the disease likely contributed to our inability to reproduce the disease in this study.

Effect of antibiotics in milk replacer on fecal shedding of Escherichia coli O157:H7 in calves

The objective of this study was to compare the concentration and duration of fecal shedding of Escherichia coli O157:H7 between calves fed milk replacer with or without antibiotic (oxytetracycline and neomycin) supplementation. Eighteen 1-wk-old Holstein calves were orally inoculated with a strain of E. coli O157:H7 (3.6 x 10(8) cfu/calf) made resistant to nalidixic acid (NA). Rectal samples were obtained three times weekly for 8 wk following oral inoculation. Fecal shedding of NA-resistant E. coli O157:H7 was quantified by direct plating or detected by selective enrichment procedure. Eight weeks after inoculation, calves were killed, necropsied, and tissues (tonsils, retropharyngeal and mesenteric lymph nodes, and Peyer's patches) and gut contents (rumen, omasum, abomasum, ileum, cecum, colon, and rectum) were sampled to quantify or detect NA-resistant E. coli O157:H7. The percentage of calves shedding NA-resistant E. coli O157:H7 in the feces in the antibiotic-fed group was higher (P < 0.001) early in the study period (d 6 and 10) compared with the control group fed no antibiotics. There was no difference between treatment and control groups in the concentration of E. coli O157 in feces that were positive at quantifiable concentrations. A comparison of the duration of fecal shedding between treated and untreated calves showed no significant difference between groups. At necropsy, E. coli O157:H7 was recovered from the rumen and omasum of one calf in the control group and from retropharyngeal lymph node and Peyer's patch of two calves in the antibiotic group. Supplementation of milk replacer with antibiotics may increase the probability of E. coli O157:H7 shedding in dairy calves, but the effect seems to be of low magnitude and short duration.

Comparison of digestive microflora between feedlot cattle with and without infection byCryptosporidium andersoni

The influence of cryptosporidial abomasitis on digestive anaerobic microflora in feedlot cattle with spontaneous Cryptosporidium andersoni colonization of abomasum was shown. Significant differences were found after the cultivation of abomasal content. Scopulariopsis brevicaulis was detected in damaged areas of infected abomasum. PCR analysis of ruminal fluid showed no differences between the two animal groups regarding qualitative composition of anaerobic and facultative anaerobic rumen microflora. The concentration of volatile fatty acids (acetate, propionate, butyrate) and ammonia in the rumen content showed that examined metabolic parameters were within normal limits except for ammonia content, which was higher in infected (291 mg/kg) than in healthy animals (203 mg/kg).

Effect of diet on Shiga toxin-producing Escherichia coli (STEC) growth and survival in rumen and abomasum fluids

The gastrointestinal tract of ruminants is the main reservoir for Shiga toxin-producing Escherichia coli (STEC) strains, potentially pathogenic for humans. We used for the first timerumen fluid in which no exogenous carbon source or other supplement was added to compare acid resistance and growth of STEC in physiological physico-chemical conditions. We showed that acidic conditions resulting from the combination of high volatile fatty acid concentration and moderately acidic pH did not alter the survival of STEC, and that human non-O157:H7 STEC isolates were able to persist in the rumen contents in spite of acid stress, low oxygen availability and nutrient deprivation, in the same manner as bovine STEC isolates do. Furthermore, our results support the hypothesis that a grain-rich diet may induce mechanisms of STEC acid resistance in the rumen that allow STEC survival in the abomasum.

Abomasitis associated with multiple antibiotic resistant Salmonella enterica serotype Typhimurium phagetype DT104

Salmonella enterica serotype Typhimurium phagetype DT104 is a multiple antibiotic resistant pathogen that has been purported to be more pathogenic than other Salmonella. In this study, we evaluated the possibility that DT104 is the causative agent of veal calf abomasitis observed in four independent outbreaks of salmonellosis. This study was undertaken to determine if the outbreaks might be due to hypervirulent S. enterica serotype Typhimurium phagetype DT104 (DT104) since Salmonella does not usually cause abomasitis. Tissues and fluids from these calves were subjected to bacteriologic culture. Pure Salmonella cultures were then used in bovine challenge experiments. DT104 was identified as the causative agent of abomasitis in calves. Thus, abomasitis is a potential indicator of infection with multiple antibiotic resistant DT104 and adds credence to the apparent hypervirulence of this pathogen.

Are goats naturally resistant to gastric Helicobacter infection?

Gastric Helicobacter species are widespread and have been reported in wild and domestic mammals of different dietary habits such as humans, dogs, cats, macaques, mice, cheetahs, ferrets, swine and cattle. All have been associated with gastric pathologies. Recently, gastric Helicobacter species were shown to be widespread in cattle and swine in Europe, and there is a report of Helicobacter pylori in sheep in Italy. However, there are no reports of Helicobacter infection in the goat, another important domestic animal of human consumption. The aim of our study was to assess whether Helicobacter abomasal infection was common in goats slaughtered for human consumption. Infection was detected through PCR analysis of DNA extracted from gastric biopsies, using genus- and species-specific primers. Bovine and porcine gastric samples were also analyzed as positive controls. None of the 70 goats were positive for Helicobacter spp.; however, Candidatus Helicobacter bovis and Candidatus Helicobacter suis were detected in 85% of the bovine and 45% of the porcine samples, respectively. We discuss the possibility that goats may exhibit natural resistance to abomasal infection by Helicobacter spp.

Development of a selective medium for isolation of Helicobacter pylori from cattle and beef samples

Helicobacter pylori has been isolated from the human stomach with media containing only minimal selective agents. However, current research on the transmission and sources of infection requires more selective media due to the higher numbers of contaminants in environmental, oral, and fecal samples. The objective of this study was to develop and evaluate detection techniques that are sufficiently selective to isolate H. pylori from potential animal and food sources. Since H. pylori survives in the acidic environment of the stomach, low pH with added urea was studied as a potential selective combination. H. pylori grew fairly well on H. pylori Special Peptone plating medium supplemented with 10 mM urea at pH 4. 5, but this pH did not sufficiently inhibit the growth of contaminants. Various antibiotic combinations were then compared, and a combination consisting of 10 mg of vancomycin per liter, 5 mg of amphotericin B per liter, 10 mg of cefsulodin per liter, 62,000 IU of polymyxin B sulfate per liter, 40 mg of trimethoprim per liter, and 20 mg of sulfamethoxazole per liter proved to be highly selective but still allowed robust colonies of H. pylori to grow. This medium was highly selective for recovering H. pylori from cattle and beef samples, and it is possible that it could be used to enhance the recovery of this bacterium from human and environmental samples, which may be contaminated with large numbers of competing microorganisms.

Sarcina -like bacteria, Clostridium fallax and Clostridium sordellii in lambs with abomasal bloat, haemorrhage and ulcers

A study of abomasal disease in lambs aged 2-5 weeks, made during the period 1993-1998, included 67 cases and 45 non-affected controls. Gross pathological findings included various combinations of bloat, haemorrhage and ulcers in the abomasum. Sarcina -like bacteria were found in sections and smears from the abomasum of 79% (53/67) of the cases. From one case, a lamb with abomasal bloat, the anaerobic "packet"-forming Sarcina ventriculi was cultivated from the abomasal contents and identified by biochemical reactions and sequencing of the 16S rRNA gene. Sarcina -like bacteria were observed microscopically in specimens from 94% (44/47) of the lambs with abomasal gas and in 45% (9/20) of those with ulcers or haemorrhage or both but little gas. On culture, abomasal contents from 41 cases yielded Clostridium fallax from 16 (39%) and Clostridium sordellii from eight (20%); abomasal cultures from 30 control lambs were negative for the three bacterial species. Quantitative cultivation, carried out on abomasal contents from live lambs and lambs dead </=3 h, showed that Clostridium perfringens, Escherichia coli and Lactobacillus spp. were present in the majority of both cases and controls, with no significant differences in the mean numbers.

Phylogenetic characterization of 'Candidatus Helicobacter bovis', a new gastric helicobacter in cattle

Recently helicobacter-like organisms have been reported in the pyloric part of the abomasum of calves and adult cattle. Cultivation of these spiral bacteria has not been successful to date. In the present study, comparative 16S rDNA sequence analysis was used to determine the taxonomic position of these bacteria. Seven abomasal biopsies of adult cattle were sampled from different Belgian and Dutch farms. In all samples the presence of helicobacter-like organisms was demonstrated by biochemical, immunohistochemical and electron microscopical data. Bacterial 16S rDNA was amplified by PCR and sequences were determined either by direct or indirect sequence analysis. Pairwise comparisons revealed all sequences to be more than 99% homologous. Phylogenetic analysis placed the organism, corresponding to the reference sequence R2XA, within the genus Helicobacter. A diagnostic PCR assay was designed, differentiating all of the bovine 16S rDNA sequences from Helicobacter and Wolinella species. The low similarity level towards Helicobacter bilis (92.8%), its closest validly named neighbour, indicates that this novel taxon is indeed a novel Helicobacter species. An in situ hybridization procedure associated the bovine sequences to the helicobacter-like organisms in the abomasum. The name 'Candidatus Helicobacter bovis' is proposed for this new abomasal helicobacter from cattle.

Hypergastrinaemia, abomasal bacterial population densities and pH in sheep infected with Ostertagia circumcincta

Serum gastrin and pepsinogen concentrations, food intake, abomasal pH and abomasal aerotolerant and anaerobic bacterial populations were measured in sheep infected with Ostertagia circumcincta to search for links between hypergastrinaemia, food intake and changes in the abomasal environment. Abomasal pH and serum gastrin and pepsinogen concentrations were elevated in each of five sheep infected via abomasal cannulae with 150000 exsheathed larval stage three, followed 11 days later by 100000 sheathed larvae given intraruminally. Unparasitised abomasa contained aerotolerant bacterial population densities of between 10(3) and 10(6) cells ml(-1) and these did not change significantly following parasitism. In contrast, anaerobic bacterial population densities increased markedly by about 10(4)-fold following parasitism. Anaerobic numbers changed rapidly when abomasal pH increased from 2.5 to 3.5. At pH 4 and above, anaerobic bacterial numbers approached levels expected in rumen contents but parameters other than pH did not relate to bacterial numbers. Brief periods when serum gastrin was lower than expected, coinciding with raised abomasal pH, were not explicable by increased bacterial numbers. Food intake, which decreased for a variable period from around Day 5 p.i., correlated poorly with serum gastrin concentration, suggesting hypergastrinaemia is not the sole cause of anorexia in parasitised animals. The survival of substantial numbers of rumen bacteria in the abomasum at only slightly raised pH may significantly lower the bacterial protein available to the sheep.

[The occurrence of spiral-shaped bacteria in the abomasum of cattle]

The goal of this study was to determine whether Helicobacter pylori or similar bacteria are present in the abomasum of cows. The abomasa of 112 clinically healthy cows were examined at slaughter. Prior to macroscopic examination, samples for bacteriological and histological examination were obtained from the fundus and from the pylorus. Bacteriological examination of the abomasal mucosa included the urease test, the microscopic examination of a Gram's stained smear, and culture on various solid media. Samples from the pylorus (63) were more often positive in the urease test than those from the fundus (35). Examination of Gram's stained smears revealed two groups of suspicious microorganisms; spiral-shaped and rod-shaped bacteria, whereby the latter could not be differentiated morphologically from Helicobacter pylori. Spiral-shaped bacteria were more often isolated from the pylorus (101 samples) than from the fundus (30 samples). The bacteria that resembled Helicobacter pylori were found in seven samples from the pylorus and in seven samples from the fundus. Helicobacter pylori was not cultured in any of the abomasal samples. Tissue samples from the fundus and pylorus were stained with hemalum and eosin and with silver according to Warthin-Starry. All but one abomasum had diffuse infiltration of lymphocytes and plasma cells. Lymphocytic follicles were observed in 109 abomasa. Neutrophils were seen in four abomasa, eosinophils in 37 and parasitic lesions in 20. As in the Gram's stained smears, spiral-shaped and rod-shaped bacteria were seen in silver-stained smears. Spiral-shaped bacteria were found in the pylorus of 96 abomasa and in the fundus and pylorus of one abomasum. The rod-shaped bacteria could not be differentiated from Helicobacter pylori by light microscopy. They were seen in glandular lumina of the superficial region of the mucosa in 97 abomasa. They were limited to the pylorus and fundus in 16 and 59 cases, respectively, and occurred in both these areas in 23 cases. The results of this study indicate that spiral-shaped bacteria may be found frequently in the bovine abomasum. Further investigations are required to determine whether these bacteria are associated with the inflammatory lesions that were observed and whether they play a role in the pathogenesis of abomasal ulcers.

Abomasal bloat associated with Sarcina-like bacteria in goat kids

An epizootic of abdominal tympany in goat kids as a result of abomasal bloat associated with a short duration of clinical signs was fatal in over 200 kids. Histologic examination of sections of abomasum revealed high numbers of bacteria that were morphologically identical to Sarcina sp. Sarcina sp are anaerobic, gas-producing organisms that could cause abomasal bloat. Other reports have proposed that abomasal bloat is caused by abnormal abomasal flora; we propose that in the goat kids reported here, Sarcina sp may represent the abnormal flora.

The bovine placentome in bacterial and mycotic abortions

Placentomes were extracted from the uteri of 22 aborted cows and examined to detect the cause of abortion; fetuses or fetal abomasal contents from 15 of the cows were also examined. Firm diagnoses of Pasteurella haemolytica, Actinomyces pyogenes, Listeria monocytogenes, Bacillus licheniformis, Aspergillus fumigatus or Mortierella wolfii abortion were made in 11 cases. The histopathological lesions showed some correlation with the identity of the bacterium isolated; the lesions of mycotic abortion were distinct and characterised by a coagulative necrosis. The removal of a placentome was not followed by any observable deleterious effects.

The potential of nematophagous fungi to control the free-living stages of nematode parasites of sheep: in vitro and in vivo studies

Following in vitro screening investigations on approximately 100 nematophagous fungi reported previously, eight species were selected for further investigation. Fungal elements (mycelium and conidia) were subjected to in vitro stress selection designed to simulate rumen and abomasal conditions. From these studies, three species, namely, Arthrobotrys oligospora, Arthrobotrys oviformis and Geniculifera eudermata, were selected for in vivo survival studies in sheep surgically fitted with abomasal and ileal cannulae. Doses of fungal conidia were administered orally or via the abomasal cannulae and samples of digesta were taken from the abomasum, the terminal ileum and faeces. The viability of the three fungal species at these sites was demonstrated. The abundance of fungi throughout the gut was dose-dependent but in all cases only very small volumes of fungal suspension containing unprotected conidia were used. These results demonstrate that a practical means of orally administering nematophagous fungi to control free-living stages of nematodes in faeces may become an achievable objective.

Phycomycosis of the abomasum in Camelus dromedarius

Two cases of phycomycosis of the abomasum in dromedary camels are described. In one of the cases there is evidence of spread to the liver. The pathology and pathogenesis of the disease are discussed. We believe this is the first report of phycomycosis in Camelidae.

Crossed immunoelectrophoresis of fungal antigens in tissues as a means of diagnosing systemic aspergillosis and zygomycosis in cattle

A novel method for diagnosing bovine aspergillosis and zygomycosis is described. Rabbit hyperimmune antisera raised against somatic antigens of Aspergillus fumigatus and Absidia corymbifera were used in crossed immunoelectrophoresis with supernatants from disintegrated tissues from acute necrohaemorrhagic mycotic lesions from cattle. The method specifically identified 4 of 5 lesions with aspergillosis and 2 of 5 lesions with zygomycosis. One lesion dually infected with aspergillosis and zygomycosis was negative. The method worked with unabsorbed sera, was specific, and required only standard electrophoretic equipment. It can therefore supplement chemical detection of fungi in tissues in the diagnosis of bovine aspergillosis and zygomycosis.

[Histological studies of the occurrence of organisms shaped like Campylobacter in the abomasum of calves]

The mucosa of the abomasum is a strongly acidic and therefore germ poor, but not entirely germfree environment. Only in isolated areas of the fundic glands zone were straight rods in the foveolas, and even more seldom spiral shaped bacteria could be encountered. They had no relation to the inflammatory infiltrates. On the other hand, Campylobacter-like organisms were more often observed in the pyloric region and, preferably, in a narrow zone following the cutaneous mucosa of the omasum. These organisms appeared to have a different size (1.3 to 2.4 microns length and 0.4 to 0.8 microns width) and they occurred deep inside the glands in an almost pure fashion. Whereas they caused no visible reaction of the tissue in the narrow cardiac zone, their occurrence in the pyloric region was several times connected with neutrophilic-rich infiltration. It ought to be tested, whether Helicobacter are among these Campylobacter-like organisms, which cause a disease leading up to ulcerations in calves similar to gastritis B in humans.

[Possible significance of spiral-shaped bacteria in the etiology of abomasal ulcers in adult cattle]

Enzyme-chemical and histological evaluations were used to examine the abomasal mucosa of adult cattle with or without mucosal lesions of the corpus. Urease activity was detected with the CLO (Campylobacter-like organisms) test in the abomasal mucosa of all cattle except one, which had mucosal lesions. Spiral-shaped bacteria were visualised histologically in the mucus layer, with the highest number being found in the pars pylorica. Variable amounts of intra-epithelial mucin were found in the corpus and pars pylorica of both test and control cattle. Most inflammatory cells were found in the lamina propria of the pars pylorica. It is suggested that spiral-shaped bacteria, together with a diminished mucosal barrier, play a role in the pathogenesis of abomasal ulcers in adult cattle.

Laboratory findings associated with abomasal ulcers/tympany in range calves

The etiology of abomasal ulcers/tympany was investigated in 48 animals from 36 ranches in Wyoming and Nebraska. Results indicate that subclinical trace mineral deficiencies of copper and/or selenium exist in the range cattle in west central Nebraska and Wyoming. Etiological agents most frequently incriminated by bacteriologic cultures and/or histopathic examination were Clostridium perfringens and Campylobacter species. Histopathologic evaluation of abomasums revealed 31 of 38 cases contained abundant gram-positive bacteria associated with the damaged abomasal mucosa. Campylobacter-like organisms were demonstrated in 9 of 38 cases using the modified Dieterle stain. Clostridium perfringens was isolated in 14 of 38 cases, and Campylobacter jejuni was recovered from 5 of 38 cases.

Ruminant forestomach and abomasal mucormycosis under rumen acidosis

Spores of Absidia corymbifera were inoculated orally into sheep with ruminal acidosis produced by feeding barley. Lesions, which developed in forestomachs of all four inoculated cases, included desquamation of superficial layers of the mucosae and focal necrosis from lamina propria to muscular layers. Granulomatous lesions were in the submucosa of three sheep. Lesions in the abomasum (two sheep) included focal necrosis, diffuse hemorrhages, and infiltration of neutrophils. All lesions were accompanied by mycotic proliferation. These results show that A. corymbifera can invade forestomach mucosae through degenerate epithelium resulting from ruminal acidosis.

Enterocolitis in cattle associated with Yersinia pseudotuberculosis infection

A syndrome in cattle of diarrhoea and death associated with enteric Yersinia pseudotuberculosis infection is described. Outbreaks occurred during winter and early spring in adult cattle grazing pastures waterlogged by recent flooding or persistent heavy rain. Antibiotic therapy was effective early in the course of the syndrome. At necropsy there was severe acute enterocolitis, and bacteria consistent with Y. pseudotuberculosis were observed in the lesions. This organism could usually be isolated from the intestines of affected animals but was recovered less often from other organs. Representative isolates were identified as Y. pseudotuberculosis serotype III. The association of this syndrome with waterlogged pastures and low temperatures suggests that these conditions favour transmission of Y. pseudotuberculosis infection in cattle. The role of Y. pseudotuberculosis as primary pathogen requires confirmation.

Candida abortion in cattle

In a retrospective study, four cases of yeast-associated abortion were found among 1,323 bovine abortions during a 5-year period at the New York State College of Veterinary Medicine. Tissues were examined histologically, and results of virological testing and microbiological culture were reviewed. Candida parapsilosis was the only pathogenic agent demonstrated in these four cases. Placental lesions consisted of necrotizing placentitis with large numbers of yeasts within trophoblasts. Secondary fetal infection occurred in all four cases, with histological lesions or isolation of Candida from the lung, liver, intestines, abomasum, and heart. A tentative diagnosis of Candida parapsilosis-induced abortion in cattle can be made on the characteristic intracytoplasmic yeasts in placental trophoblasts.

Isolation of Clostridium perfringens from neonatal calves with ruminal and abomasal tympany, abomasitis, and abomasal ulceration

Eight neonatal calves (2 to 21 days old) with suspected abomasal displacement or intestinal obstruction after acute onset of abdominal tympany, colic, depression, or death were referred to Kansas State University for clinical examination or for necropsy. Results of routine hematologic and serum chemical analyses did not reveal consistent changes. Necropsy revealed abomasal distention, with various degrees of abomasitis, hemorrhage, and ulceration, but did not reveal evidence of displaced abomasum or obstructed intestine. Specimens of ruminal contents collected via stomach tube or at necropsy and abomasal contents collected at necropsy were obtained for anaerobic bacteriologic culture. Clostridium perfringens was isolated from all specimens, and on the basis of toxin neutralization tests in mice, 7 were type A and one was type E. Copper concentrations in serum and tissues were within normal limits. It appeared that the acute abdominal syndrome in these neonatal calves was unrelated to copper deficiency, and that C perfringens, particularly type A, may have had an appreciable contributory role in its pathogenesis.

Factors influencing the survival and multiplication of bacteriophages in calves and in their environment

Seven phages were fairly susceptible in vitro to the lethal effect of acidified whey, more so than the enteropathogenic Escherichia coli strains on which they were active. The low acidity that prevailed in the abomasum contents of calves shortly after a milk feed had little harmful effect on orally administered organisms of these phages; they flooded into the small intestine. The high acidity that prevailed later was lethal to orally administered phage organisms; few entered the small intestine. The lethal effect could be counteracted by giving CaCO3 in the feed. Low concentrations of phage-neutralizing antibodies were found in some serum samples from human beings, cattle and pigs. Antibodies to one of the seven phages were common in the human samples and antibodies to another, phage B44/1, were common in the cattle and pig samples and in bovine colostrum. Phage B44/1 antibodies in a sample of colostral whey were destroyed at pH 3.25 or less. Giving colostrum containing phage B44/1 antibodies with CaCO3 to a calf greatly reduced the numbers of orally administered phage B44/1 organisms in its alimentary tract. Antibodies to another phage were induced in the serum of a calf suffering from E. coli diarrhoea by treating it with that phage. The phages were as susceptible as the E. coli strains to the lethal action of formaldehyde and sodium hypochlorite. In contrast to the E. coli strains, they were almost completely resistant to phenol and chloroxylenol. The in vitro virulence of 21 phages varied according to the temperature at which tests were performed.(ABSTRACT TRUNCATED AT 250 WORDS)

Physiological and microbiological changes in the abomasum of sheep infected with large doses of Haemonchus contortus

The pH, PO2 and the number of viable bacteria per ml of abomasal fluid were recorded before and after administering large doses of infective larvae of H. contortus to sheep. Highly significant increases were observed in the pH, in numbers of viable bacteria and in the proportion of oxygen-sensitive bacteria in the abomasal fluid during the first 10 to 14 days of infection. At the same time a decrease in the abomasal fluid PO2 was recorded. Subsequently a slow recovery of pH, PO2 and bacterial numbers to pre-infection values ensued. The microbiological and physiological changes occurring in the abomasum of sheep after infection with H. contortus are discussed with reference to these results.

The effects of different sources of nitrogen supplementation on the post ruminal flows of organic matter and different nitrogenous constituents in steers

Friesian steers, virtually protozoa free, were equipped with simple rumen and abomasal cannulas. They were given diets consisting of approximately equal proportions of ground, pelleted alkali treated straw and a rolled barley, tapioca mixture supplemented with urea + casein (UC), soybean meal (SBM), 'normal' white fishmeal (NDF) or white fishmeal designated as being of 'low' rumen degradability (LDF). The diets were isoenergetic (the protein sources replacing part of the tapioca) and they were given in amounts to supply sufficient metabolizable energy (ME) to support an average growth rate of 0.5 kg/d. Rumen degradable nitrogen (RDN): ME values were estimated to be 2.08, 1.40, 1.90 and 1.66 for diets UC, SBM, NDF and LDF respectively. RNA, alpha-epsilon-diaminopimelic acid and 35S (added as sulphate) were used as bacterial markers. Chromic oxide and polyethylene glycol (PEG) were given as flow markers and flows (g/24 h) at the abomasum of organic matter (OM) and nitrogenous constituents were calculated. Rumen volumes and ruminal liquid fractional outflow rates were measured using PEG. Samples of mixed rumen bacteria separated from strained rumen digesta from animals receiving diet UC contained significantly less DAP-N (0.322 g/kg DM) than those from animals receiving diets SBM, NDF or LDF (0.530 g/kg DM). Mean rumen volume (approximately 15 l) and liquid fractional outflow rates (approximately 0.105/h) were similar on all diets but there was appreciable variation between animals. The proportion of OM intake digested in the rumen was similar on all diets. The proportional contribution of bacterial-N to the total non-ammonia-N passing the abomasum based on mean values derived from DAP and 35S as markers was 0.57, 0.47, 0.39 and 0.31 for diets UC, SBM, NDF and LDF respectively. Corresponding values based on RNA were 0.71, 0.50, 0.48 and 0.35 respectively. Bacterial-N (RNA) flows at the abomasum were 31, 25, 26 and 20 g/d for diets UC, SBM, NDF and LDF respectively. Corresponding values for 35S and DAP were 26, 24, 21 and 18 g/d respectively. Values derived from RNA flows were consistently and significantly higher (P less than 0.01) than those based on DAP or 35S. Mean estimated efficiencies of bacterial protein synthesis (g bacterial-N/kg OM truly digested) were 15, 15, 14 and 12 for diets UC, SBM, NDF and LDF respectively.(ABSTRACT TRUNCATED AT 400 WORDS)

Efficacy of the tris-salt of 2 [(methoxycarbonylamino)-[2-nitro-5-(n-propylthio) phenylimimo] methylamino] ethane sulfonic acid against inhibited larvae of Ostertagia ostertagi

The tris-salt of 2-[(methoxy-carbonylamino) - [2-nitro-5-(n-propylthio) phenylimimo] methylamino] ethane sulfonic acid (MCA) was evaluated against naturally acquired gastrointestinal parasitism in cattle during spring in Louisiana to determine efficacy of the compound against inhibited early 4th-stage larvae (EL4) of Ostertagia ostertagi. Forty-three crossbred yearling beef heifers were grazed together on contaminated pastures between Mar 1 and Apr 18, 1984. On April 17, 3 of the 43 heifers were slaughtered. Analysis of worm population characteristics in the 3 cattle indicated sufficient numbers of O ostertagi EL4 and other worm genera and species in these cattle to pursue a valid evaluation of the anthelmintic efficacy of MCA. The remaining 40 heifers were removed from pasture on April 18. On April 24, they were allotted into 4 treatment groups (10/group) based on an equal distribution of body weights and on whether they were spring- or autumn-born cattle. On April 25, the cattle were treated as follows: group 1, nontreated controls; group 2, treated with MCA at 7.5 mg/kg of body weight by oral drench; group 3, treated with MCA at 15.0 mg/kg by oral drench; and group 4, treated with MCA at 20.0 mg/kg by oral drench. The cattle were then confined in drylot pens until May 7. Similar numbers of cattle from each group were killed over a 3-day period from May 8 to May 10 (13 to 15 days after treatment). Mean numbers of O ostertagi recovered from nontreated controls were: adults, 8,279; developing 4th-stage larvae, 2,806; and inhibited EL4, 12,070.(ABSTRACT TRUNCATED AT 250 WORDS)

Pathological and microbiological findings in 38 lambs with watery mouth

Thirty-eight lambs with watery mouth were presented alive for necropsy. The most frequently found abnormality was enteritis, in 25 lambs. Bacteria were cultured from the gut contents of all lambs and bacteraemia was detected at high frequency at necropsy, though very much less frequently six hours before. Escherichia coli strains did not possess K99 antigen. It was concluded that absolute starvation and septicaemia were unlikely causes of the disease; that there is support for the hypothesis that reduced gut motility is an important early feature and, that if bacteria are involved in the aetiology, they may have a non-specific role.

Systemic mycosis in Scottish red deer (Cervus elaphus)

The pathological features of 10 cases of systemic infection of young red deer by fungi morphologically identified as phycomycetes are described. The most frequently affected organs were the kidneys, followed by liver and central nervous system. The fungi stimulated an acute pyogenic inflammatory reaction and a phagocytic giant cell response. Vasculitis with thrombosis and spread of fungi to the surrounding tissue was a common finding. Culture was attempted in 4 cases; one yielded Absidia, 2 Aspergillus and the other an unidentified fungal growth. Analysis of the histories suggests that, in nine of the ten cases, stressful husbandry may have been a predisposing factor.

Effects of level of dietary intake and physical form of protein supplement on the digestibilities of different dietary carbohydrates between mouth and abomasum of young steers

Steers fitted with simple rumen and abomasal cannulas were given isoenergetic diets of rolled barley and chopped straw, pelleted together with some tapioca alone (B) or with some tapioca replaced by coarse soyabean meal (M) or finely ground soyabean flour (F). The diets were given at two levels to support 0.5 (L) and 1.0 (H) kg/d live weight gain. Chromic oxide and PEG were given as digesta flow markers. Mouth to abomasum digestibilities of different dietary sugars at the low level of intake (LB) were 0.65, 0.68, 0.59, 0.56 and 0.94 for arabinose, galactose, xylose, cellulose-glucose and starch-glucose respectively. Corresponding values at the higher level of intake (HB) were 0.55, 0.66, 0.55, 0.44 and 0.93 respectively. Supplementation with either soya bean meal or flour had no significant effects on the mouth to abomasum of dietary carbohydrate digestibilities at either level of feeding.

Effects of breed, diet and sex on the alkaline phosphatase activity in walls of the bovine rumen and abomasum

Alkaline phosphatase (APase) activity in tissue samples, with adherent bacteria, was measured from two sites in the rumen and from two sites in the abomasum of 57 yearling Angus and Hereford bulls and heifers fed a high or a low energy diet. In the rumen, APase activity was higher at the caudoventral blind sac than at the dorsal sac in animals of both breeds fed the high energy diet and in Angus bulls fed the low energy diet, but the reverse was observed in Hereford bulls fed the low-energy diet (P less than .01). In the abomasum, APase levels were higher for bulls than heifers (P less than .01) and higher at the fundic than at the pyloric region (P less than .01). Morphological studies also showed that rumen samples from animals fed a high energy diet exhibited a more widely distributed APase activity and an increase in the digestive recycling of epithelial cells that produced some "pitting" of the tissue. The higher APase activity of the epithelial tissue of animals fed the high energy diet may be explained by the greater rate of cell death and renewal indicated by the higher mitotic index reported by other researchers who have studied the cell cycle of the rumen epithelium in ruminants fed high and low energy diets.

Effects of dietary milk fat (whole milk) and propionic acid on intestinal coliforms and lactobacilli in calves

Calves fed whole milk had 2,000-fold fewer (P less than 0.001) coliforms in the cranial part of the small intestine than did calves fed skim milk (fat removed). Calves fed milk with 32 mM added propionic acid had nearly 1,000-fold lower (P less than 0.001) counts of lactobacilli in the entire gastrointestinal tract than did calves fed milk without added propionic acid.

Corynebacterium equi in the gastrointestinal tract of ruminants

Corynebacterium equi has been recovered from the gastrointestinal tract of sheep and cattle. It can be found in all parts of the gut, and around 80% of animals have the organism in one or more intestinal sites. C. equi could be detected in the faeces of sheep which were kept caged and free from recontamination by the organism.

Utilization of low quality roughages: effects of urea and protein supplements of differing solubility on digesta flows, intake and growth rate of cattle eating oaten chaff

1. Expt 1. Five 150 kg steers with ruminal, abomasal and ileal cannulas were given 3000 g oaten chaff daily plus pelleted supplement with no added nitrogen (diet A) of 50 g N/d as urea (diet B), casein (diet C), casein and formaldehyde-treated casein (HCHO-casein) (50:50 w/w; diet D) and HCHO-casein (diet E), in a 5 x 5 Latin square design. The basal diet and supplement were fed in eight equal increments at intervals of 3 h. Proportions of dry matter and organic matter digested in the stomach and whole tract were greater for diets B, C, D and E than for diet A. Total volatile fatty acid levels in the rumen and the proportion of acetic acid, were lower, and the proportion of propionic acid higher on diet A than on the other diets. Rumen ammonia levels were lower on diets A, D and E than on diets B and C. N flows at the abomasum, ileum and rectum were lower on diet A than on the other diets; abomasal flows and apparent intestinal absorptions of amino acids were higher on diets D and E than on diets A, B and C. Efficiencies of bacterial protein synthesis were 15, 15, 14, 13 and 12 g bacterial N/kg OM truly digested in the stomach on diets A, B, C, D and E respectively. 2. Expt 2. Forty 300 kg steers were fed oaten chaff ad lib. plus twice the amount of the same pelleted supplements as in Expt 1. Intake of oaten chaff was 23% higher with N supplements (diets B, C, D and E) than without (diet A). Live-weight gains were 356, 798, 843, 842 and 805 g/d on diets A, B, C, D and E respectively. 3. It was concluded that efficiency of bacterial protein synthesis was not limited by the supply of peptides and amino acids in the rumen, and that increases in amino acid availability in the intestines from feeding HCHO-casein did not increase food intake or live-weight gain.