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PubMed2006

Babesia spp. identified by PCR in ticks collected from domestic and wild ruminants in southern Switzerland.

Concurrent infections with vector-borne pathogens affected a cattle herd in Switzerland, and one of the pathogens was identified as Babesia bigemina, which had never been observed in this country before. Therefore, a survey of the occurrence of ruminant Babesia spp. and their tick vectors in Switzerland was conducted. A total of 2,017 ticks were collected from sheep, goats, cattle, and wild ruminants (deer, roe deer, and chamois) in southern parts of Switzerland and identified morphologically. The vast majority of the ticks (99.2%) were Ixodes ricinus, but 14 ticks from sheep and goats were identified as Dermacentor marginatus and two ticks from wild ruminants were identified as Hemaphysalis punctata. PCR analyses of 700 ticks revealed the presence of Babesia divergens (n = 6), Babesia sp. genotype EU1 (n = 14), and B. major (n = 2), whose suggested occurrence was confirmed in this study by molecular analysis, and the presence of novel Babesia sp. genotype CH1 (n = 4), which is closely related to B. odocoilei and to Babesia sp. genotype RD61 reported from North America. The identification of B. divergens and B. major in ticks collected from wild ruminants cast doubt on the postulated strict host specificity of these bovine Babesia species. Furthermore, the zoonotic Babesia sp. genotype EU1 was detected in ticks collected from domestic animals but was obtained predominantly from ticks collected from wild ruminants. More than one tick containing DNA of different Babesia spp. were collected from two red deer. Hence, the role of these game animals as reservoir hosts of Babesia spp. seems to be important but requires further investigation.

Animals↗
PubMed2006

Anaplasma phagocytophilum in ruminants in Europe.

The agent that causes tick-borne fever (TBF) in sheep was first described in 1940, 8 years after the disease was first recognized in Scotland. The same agent was soon shown to cause TBF in sheep and pasture fever in cattle in other parts of the UK, Scandinavia, and other parts of Europe. After the initial use of the name Rickettsia phagocytophila, the organism was given the name Cytoecetes phagocytophila to reflect its association with granulocytes and its morphological similarity with Cytoecetes microti. This name continued to be used by workers in the UK until the recent reclassification of the granulocytic ehrlichiae affecting ruminants, horses, and humans as variants of the same species, Anaplasma phagocytophilum. TBF and pasture fever are characterized by high fever, recurrent bacteremia, neutropenia, lymphocytopenia, thrombocytopenia, and general immunosuppression, resulting in more severe secondary infections such as tick pyemia, pneumonic pasteurellosis, listeriosis, and enterotoxemia. During the peak period of bacteremia as many as 90% of granulocytes may be infected. The agent is transmitted transtadially by the hard tick Ixodes ricinus, and possibly other ticks. After patent bacteremia, sheep, goats, and cattle become persistently infected "carriers," perhaps playing an important role in the maintenance of infection, in the flock/herd. Little is known about how efficiently ticks acquire and maintain infection in ruminant populations or whether "carrier" domestic ruminants play an important role as reservoirs of infection, but deer, other free-living ruminants, and wild rodents are also potential sources of infection. During the late 1990s serological evidence of infection of humans was demonstrated in several European countries, creating a renewed interest and increased awareness of the zoonotic potential of TBF variants. More recently, a few cases of human granulocytic anaplasmosis (HGA) have been reported in some European countries, but it remains to be established whether the variants causing HGA in Europe are genetically and biologically different from those causing TBF in ruminants. TBF is readily diagnosed by demonstrating intracytoplasmic inclusions in peripheral blood granulocytes or monocytes of febrile animals or by detecting specific DNA by polymerase chain reaction (PCR), and TBF variants of A. phagocytophilum can be cultivated in tick cell lines, but the differentiation of TBF variants from HGA variants awaits further investigations.

Anaplasma phagocytophilum↗
PubMed1998

The major histocompatibility complex of ruminants.

Studies of the major histocompatibility complex (MHC) of cattle over the past twenty years have revealed a reasonably detailed picture of the genetic organisation and function of the genes within this genetic system. Serological and biochemical analysis of lymphocyte cell surface antigens provided the first evidence for highly polymorphic MHC genes in cattle and other ruminant species. The MHC of cattle was thus named the bovine leucocyte antigen (BoLA) system. During the past 10 years, tools of molecular biology have been used to characterise the number of MHC genes, their sequence and fine structure in a number of ruminant species. Although individual MHC genes were found to have clear orthologues among ruminants and other mammalian species, the MHC of cattle, and probably that of sheep and goats, has a unique genetic organisation. Cattle have a class II gene cluster (class IIb region) which is physically distant from all the other MHC genes on the same chromosome. Moreover, genes involved in antigen processing, such as the proteosome subunit locus LMP2, are also found in the class IIb region, demonstrating that these genes need not be in close proximity to other MHC genes to function normally. The MHC class I and class II gene products of ruminants present processed peptides to T lymphocytes which mediate helper and cytotoxic functions. Identification of peptide binding motifs of cattle MHC class I molecules indicates that ruminant MHC molecules function in a similar manner to those of mice and humans. These functional studies provide a firm molecular basis for a number of well-documented associations with infectious diseases, although a detailed understanding of the immunogenetic mechanisms underlying these associations has yet to be elucidated.

Animals↗
PubMed1990

Immune responses against Toxoplasma and Sarcocystis infections in ruminants: diagnosis and prospects for vaccination.

Toxoplasma gondii and a variety of Sarcocystis species are common cyst-forming coccidian parasites of domestic ruminants worldwide. T. gondii infection is a major cause of ovine and caprine abortion and perinatal mortality, but does not appear commonly to cause significant disease in other ruminants. Sarcocystis infections are probably most important in growing ruminants in which they can cause subclinical anaemia and reduced weight gain. The life cycles, pathogenesis and current knowledge of immunity to these protozoa, in ruminants, are reviewed. Although clinical signs may suggest a diagnosis, confirmation requires the use of specific immunological methods such as serology and immunohistochemistry. These are discussed and the necessity for using characterised antigens and antisera is emphasised. Whereas live Toxoplasma "vaccines" may be effective in sheep and goats, the eventual preparation of a killed vaccine capable of inducing long-term protection is of the utmost importance. To achieve this goal it will be necessary to identify the specific antigens capable of stimulating protective immunity and to conduct further research on both the pathogenesis of toxoplasmosis and fundamental aspects of the immune response of pregnant ruminants to T. gondii.

Animals↗
PubMed1995

Characteristics of plant cell walls affecting intake and digestibility of forages by ruminants.

Even under the intensive concentrate feeding systems of ruminant animal production in the United States, forages continue to represent the single most important feed resource. Cell-wall concentration and digestibility limit the intake potential and energy availability of forage crops in beef and dairy production. Identification of cell-wall characteristics that should be targets of genetic modification is required if plant breeders and molecular biologists are to successfully improve forages for livestock feeding. As the forage plant cell develops, phenolic acids and lignin are deposited in the maturing cell wall in specific structural conformations, and in a strict developmental sequence. Lignin is the key element that limits cell-wall digestibility, but cross-linkage of lignin and wall polysaccharides by ferulic acid bridges may be a prerequisite for lignin to exert its affect. Lignin composition and p-coumaric acid in the wall are less likely to affect digestibility. Voluntary intake of forages is a critical determinant of animal performance and cell-wall concentration is negatively related to intake of ruminants consuming high-forage diets. Cell walls affect intake by contributing to ruminal fill. A simple model of cell-wall digestion and passage in which ruminal fill is a function of rates of digestion and passage, as well as the indigestible fraction of the cell-wall indicates that cell-wall concentration and rate of passage are the most critical parameters determining ruminal fill. Plant factors that affect rate of passage include those that affect particle size reduction by chewing and those that affect particle buoyancy in the rumen. The latter is primarily affected by 1) the ability of the particulate matter to retain gases, which is probably related to plant anatomy and rate of digestion of the plant tissue, and 2) the rate at which the gas is produced, which is affected by the potentially digestible fraction of the particulate matter and the rate of digestion of this fraction. Increasing rate of digestion should increase rate of passage by diminishing the gas produced and increasing density over time. A reduction in the indigestible cell-wall fraction is beneficial because this will decrease fill and increase digestibility. Animal production and economic benefits from reduced cell-wall concentration and increased digestibility are significant. Because of the high cell-wall concentration and large digestible cell-wall fraction of grasses, reduction in cell-wall concentration would probably be of greater value than improving digestibility in these species. Legumes represent the opposite situation and may benefit more from improvements in the digestibility of their cell walls.

Animal Feed↗
PubMed1986

Grain processing effects on starch utilization by ruminants.

Starch utilization may be markedly enhanced by proper grain processing; however, extent of improvement is primarily dependent upon the ruminant species, grain source and method of processing. Grain processing has less impact on starch digestion by sheep than cattle. The magnitude of improvement is inverse to the starch digestion values for nonprocessed (or minimally processed) grains. Utilization of sorghum grain starch is improved most by extensive processing, and then corn, with little improvement in barley starch digestion. Studies comparing processing effects on barley or wheat starch utilization by cattle were not found. Steam-flaking consistently improves digestibility of starch by cattle fed corn- or sorghum grain-based diets over whole, ground or dry-rolled processes. Other extensive processing methods appear to enhance starch digestibility of corn and sorghum grain to a similar extent as steam-flaking, but comparative data are too limited to quantitate adequately effects of these methods. This improvement in starch utilization appears to be the primary reason for enhanced feed conversion of cattle fed diets high in these processed grains. The major site of cereal grain starch digestion is usually the rumen. Processing increases microbial degradation of starch in the rumen and decreases amounts of starch digested post-ruminally. Rates of in vitro amylolytic attack of starch in cereal grains by both ruminal microbial and pancreatic enzyme sources are improved by processing methods employing proper combinations of moisture, heat and pressure. In vitro and in situ studies suggest that much of the increase in ruminal starch fermentation with steam-flaking is due to changes in starch granular structure, which produces additive effects beyond those of decreasing particle size. Thus, efficiency of ruminal starch fermentation by cattle appears to be improved by proper processing of corn and sorghum grain. Processing and grain source studies both suggest that maximal total tract starch digestibility is positively related to the extent of digestion in the rumen.

Animal Feed↗
PubMed1992

Metabolism of albendazole and albendazole sulphoxide by ruminal and intestinal fluids of sheep and cattle.

1. The metabolism of albendazole (ABZ), albendazole sulphoxide (ABZSO) and albendazole sulphone (ABZSO2) by ruminal, abomasal and ileal fluids of sheep and cattle was investigated under anaerobic conditions in vitro. 2. None of the compounds was metabolically changed by incubation with abomasal fluids of sheep and cattle. 3. ABZ and ABZSO were extensively metabolized by sheep and cattle ruminal and ileal fluids. ABZSO2 was unaffected by incubation with these gastrointestinal fluids. 4. The rate of ABZ oxidation into ABZSO was greater for cattle ruminal and ileal fluids than for sheep fluids. 5. ABZSO was reduced back to ABZ by ruminal and ileal fluids of both species. This reducing activity was significantly higher for both ruminal and ileal fluids of sheep compared with those of cattle.

Abomasum↗
PubMed1993

Nutritional regulation of postruminal digestive enzymes in ruminants.

Nutritional regulation of digestive enzymes has received limited study in ruminants. Comparable studies with nonruminants report adaptations occurring in pancreatic and mucosal enzyme concentrations and synthesis in response to increased consumption of carbohydrate, lipid, or protein. Adaptations in carbohydrases apparently are mediated through changes in blood glucose and insulin, and changes in lipase are mediated through changes in circulating beta-hydroxybutyrate. Increased synthesis and secretion of pancreatic proteases apparently are mediated directly through luminal effects of protein, possibly through a messenger peptide. Available information for ruminants suggests that pancreatic alpha-amylase concentration increases with increased energy intake, but not with increased carbohydrate intake, independent of energy. This result may indicate an adaptation mechanism similar to that of nonruminants, one that is mediated through increased glucose turnover, not intestinal carbohydrate supply alone. Increased intake of energy or increased intestinal supply of carbohydrates results in little or no increase in mucosal carbohydrases in the ruminant. Comparable data for effects of changing intestinal supply of protein are limited to the developing ruminant. Experiments involving lipid feeding are not available, but duodenal lipid infusion decreases pancreatic lipase secretion. Ruminant data are inadequate to predict accurately an adaptive response to feeding any diet.

Animal Nutritional Physiological Phenomena↗
PubMed2000

Seroepidemiology of chlamydial infections of wild ruminants in Spain.

Chlamydial infections were determined serologically among wild ruminants in the Nature Park of the Sierras de Cazorla, Segura y Las Villas (CNP; Spain). Sampling was done during the period from 1990-95. There were 1,244 blood samples collected, consisting of 490 from fallow deer (Dama dama), 343 from mouflon (Ovis mussimon), 283 from red deer (Cervus elaphus) and 128 from Spanish ibex (Capra pyrenaica). Specific complement-fixing antibodies of Chlamydia spp. were detected by means of microtechnique, using lipopolysaccharide antigen. The relationship of biological (species, sex, age), temporal (year) and territorial (central and peripheral areas) factors to seropositive prevalence was examined, and preliminary data were collected on whether or not sheep and goat herds grazing in the peripheral areas of the park also were infected with Chlamydia spp. Chlamydiosis was common in the four species of wild ruminants in the CNP in all the years studied. The prevalence of Chlamydia sp. in mouflon (37%) was significantly greater than in fallow deer (30%), and both had a significantly higher prevalence rate than Spanish ibex and red deer (both 24%). The four species of wild ruminants were similar in that they act as reservoirs of Chlamydia spp., although their receptivity may be different, and the infection can certainly be maintained among these animals by intra-group transmission. The differences in prevalences and geometric mean titers (GMT), both between the sexes (male versus female) and between different ages (adult versus juvenile), were insignificant in all four species. For all species of wild ruminants both prevalence rates and GMTs were greater in populations occupying the peripheral areas of the park than in those inhabiting the central area. Herds of sheep and goats had a high prevalence of chlamydiosis. Intertransmission of Chlamydia sp. between wild and domestic ruminants occurred through grazing on the same pastures. The highest mean prevalence (44%) of patent infections (CFT titers of > or =1:80) was detected in red deer, although this frequency was not significantly different from those observed in mouflon (39%), Spanish ibex (38%), and fallow deer (37%). The proportion of patent infection was higher in females than in males, and none of the juveniles (<2-yr-old) showed patent infections. The prevalence of predicted patent chlamydial infections was always higher in the peripheral areas of the park, although only among mouflon and fallow deer were the differences statistically significant.

Animals↗
PubMedDate not supplied

[Cationic hydrogen exchanges in the reticulo-rumen and their significance in ruminants].

Up-to-date experimental results on mechanisms and physiological significance of mineral cations absorption in the reticulo-rumen of ruminants are observed in the review. Up to 90% of sodium, 100% of potassium and calcium and about 30-60% of magnesium pass across epithelium of the reticulo-rumen of domestic ruminants by electroneitral way through cation per hydrogen exchanges. In wild ruminant (reindeer) the item for sodium is up to 100%. Intracellular hydrogen ions are available due to carbonic anhydrase I function. The exchanges have great significance for the animals. The first, their organisms get cations mainly by metabolic products using. The second, hydrogen ions excretion is necessary for reticulo-rumen epithelial cells successful proliferation. The third, hydrogen ions excretion may be considered as a excretory mechanism of metabolic acidosis compensation in the digestive tract of ruminants. These moments may be observed as physiological mechanisms of adaptation of wild ruminants to seasonal dynamic of nutrition.

Animals↗
PubMed1992

Regulation of branched chain amino acid metabolism in ruminants.

The regulation of branched-chain amino acid (BCAA) metabolism has been studied in ruminants mainly during the last decade. Evidences support that the rate of BCAA catabolism is lower in ruminants than in monogastrics. This is associated with a low specific BCAA aminotransferase (first catabolic enzyme) activity and a relatively low degree of activation of the second catabolic enzyme in post-natal ruminant tissues. Similarly to monogastrics in vivo BCAA catabolism involves an interorgan cooperation in ruminants. The benefic effect of leucine excess in protein turnover has also been raised. By contrast leucine excess does not stimulate the rate of isoleucine and valine catabolism in ruminants as much as in monogastrics.

Amino Acids, Branched-Chain↗
PubMed1999

Why, why, why?: Reason-giving and rumination as predictors of response to activation- and insight-oriented treatment rationales.

This study examines the relationships among the reasons a person offers for depression, the tendency to ruminate in response to depression, and reactions to activation-oriented (AO) or insight-oriented (IO) treatment rationales. Adults from the community (N=51) completed self-report measures of reason-giving and rumination and rated the credibility of, and personal reactions to, AO and IO rationales presented in written and videotape formats. Participants who gave more reasons for depression also tended to ruminate more in response to depressed mood. Reason-giving and rumination predicted lower credibility ratings and more negative personal reactions to the AO rationale. Although no relationship was found between these variables and response to the IO rationale, specific reasons were associated with different reactions to the two rationales. We discuss the roles of reason-giving and rumination in predicting responses to psychotherapies for depression.

Adult↗
PubMed1989

Variables associated with frequency of rumination in a boy with profound mental retardation.

The relationships between frequency of rumination in a boy with profound mental retardation and a variety of environmental, interpersonal, and temporal variables were investigated by collecting and analyzing data during all waking hours over a 4-week period. Low levels of rumination were associated with periods of special education programming (versus nonschool hours), individual attention (versus group activities and independent play), and time spent with caretakers who like the child (versus those who like him less). The findings also revealed a mealtime effect (decreasing rumination as time elapsed following meals) and a time of day effect (increasing rumination as the day progressed). Directions for future research and possible implications for the environmental management of rumination are discussed.

Child↗
PubMed1986

The occurrence of paranuclear vacuoles in sheep ruminal epithelium treated with distilled water in vitro and from sheep injected with a large quantity of water into the rumen.

In the histological preparation taken after animal death, paranuclear vacuoles (PV) in sheep ruminal epithelium were already present in high percentage (7.5-20.3%). With the incubation of the ruminal mucosae in distilled water (10-15 degrees C) up to 120 min, PV occurrence did not alter. With incubation in NaCl solution, however, PV value decreased with time proportional to NaCl concentration (0.5, 0.85 or 1.5%). In the preparation taken by biopsy, on the other hand, PV were rare in ruminal epithelium (less than 0.3%). With the injection of warm water (10-141/animal), however, PV occurrence in the ruminal epithelium was not affected. PV as cytoplasmic processes of the ruminal Langerhans cells are probably formed by the reaction of these cells to environmental changes in the tissue caused by animal death.

Animals↗
PubMed1976

Effect of dietary fat supplementation on the composition and positional distribution of fatty acids in ruminant and porcine glycerides.

Dietary fats which were protected from ruminal metabolism were fed to ruminants, and the constituent fatty acids subsequently appeared in the glycerides of tissues and secretory products. These dietary fat induced alterations in tissue lipid composition were particularly apparent when the fat source was enriched with linoleic acid. Similarly, when pigs were fed linoleic-enriched fats, the linoleic acid was incorporated into the adipose tissue triglycerides. Stereospecific analyses were carried out on triglycerides from various tissues and secretory products obtained from animals fed control or linoleate-enriched diets. The analysis of adipose tissue triglycerides showed that linoleate and oleate were preferentially esterified to positions 2 and 3 (cattle and sheep), and positions 1 and 3 (pigs). Of the other major adipose tissue fatty acids, palmitate was preferentially esterified at position 1 (ruminants) and position 2 (pigs), and stearate was preferentially esterified at positions 1 and 3 (ruminants), and position 1 (pigs). Stereospecific analysis of high mol wt milk triglycerides showed that linoleate was either evenly distributed on all three positions (goats), or predominantly on position 3 (cows). Furthermore, the incorporation of this linoleate did not markedly alter the positional specificity of the other major milk triglyceride fatty acids. Of these fatty acids, the short and medium chain length acids (butyratelaurate) were mainly on position 3, myristate and palmitate on positions 1 and 2, and stearate and oleate evenly distributed. Thoracic duct lymph triglycerides from sheep tended to show preferential incorporation of linoleate at position 3, palmitate at position 2, and stearate at position 1 and 3; oleate, on the other hand, tended to be evenly distributed on all three positions of the lymph triglyceride. The stereospecific arrangement of fatty acids in sheep liver triglycerides was similar to that of lymph triglycerides, and this may reflect the uptake of intact or partially hydrolysed chylomicron and/or very low density lipoprotein triglycerides by the liver. There were also some analogies in the stereospecific arrangement of fatty acids on ruminant lymph and milk triglycerides and this may reflect an incomplete hydrolysis of chylomicron and/or very low density lipoprotein triglycerides prior to uptake by the mammary gland. An unusual feature of lymph from sheep fed linoleate was the presence of phospholipids which contained large amounts of linoleate in ca. equal proportion at both positions 1 and 2 of the phospholipid molecule.

Adipose Tissue↗
PubMed2000

Effects of thymol on ruminal microorganisms.

Thymol (5-methyl-2-isopropylphenol) is a phenolic compound that is used to inhibit oral bacteria. Because little is known regarding the effects of this compound on ruminal microorganisms, the objective of this study was to determine the effects of thymol on growth and lactate production by the ruminal bacteria Streptococcus bovis JB1 and Selenomonas ruminantium HD4. In addition, the effect of thymol on the in vitro fermentation of glucose by mixed ruminal microorganisms was investigated. Neither 45 nor 90 microg/ml of thymol had any significant effect on growth or lactate production by S. bovis JB1, but 180 microg/ml of thymol completely inhibited growth and lactate production. In the case of S. ruminantium HD4, 45 microg/ml of thymol had little effect on growth and lactate production; however, 90 microg/ml of thymol completely inhibited growth of S. ruminantium HD4. Thymol also decreased glucose uptake by whole cells of both bacteria. When mixed ruminal microorganisms were incubated in medium that contained glucose, 400 microg/ml of thymol increased final pH and the acetate to propionate ratio and decreased concentrations of methane, acetate, propionate, and lactate. In conclusion, thymol was a potent inhibitor of glucose fermentation by S. bovis JB1 and S. ruminantium HD4. Even though thymol treatment decreased methane and lactate concentrations and increased final pH in mixed ruminal microorganism fermentations of glucose, concentrations of acetate and propionate were also reduced.

Animals↗
PubMed1999

Proteolytic activities of the starch-fermenting ruminal bacterium, Streptococcus bovis.

The objective of this study was to characterize the extracellular proteolytic activity of Streptococcus bovis. Strains KEG, JB1, NCFB 2476, and K11.21.09.6C produced very similar large molecular weight (160-200 kDa) extracellular proteases that were specifically inhibited by PMSF, a serine protease inhibitor. Further experiments with S. bovis KEG indicated that cultures grown with casein as the sole added N source produced the greatest level of proteolytic activity, and the level of proteolytic activity was independent of growth rate. Clarified ruminal fluid (CRF) decreased proteolytic activity by 54% compared with cultures grown with casein alone, and addition of exogenous peptides and carbohydrates (CHO) to the CRF further reduced the level of proteolytic activity by 44% and 52%, respectively. These results suggested that the proteolytic activity of S. bovis KEG was modulated by available N source and that the proteolytic activity was present for reasons other than providing N for growth. The role of S. bovis in ruminal proteolysis requires further definition, but phenotypic similarity among some ruminal strains would suggest a common niche in ruminal proteolysis. The uniformity of proteolytic activities could make S. bovis a prime candidate for manipulation in ruminal proteolysis control strategies.

Animals↗
PubMed2005

Bicarbonate exporting transporters in the ovine ruminal epithelium.

In order to stabilize the intraruminal pH, bicarbonate secretion by the ruminal epithelium seems to be an important prerequisite. The present study therefore focussed on the characterization of bicarbonate exporting systems in ruminal epithelial cells. Intracellular pH (pH(i)) was measured spectrofluorometrically in primary cultured ruminal epithelial cells loaded with the pH-sensitive fluorescent dye, 2,7-bis(carboxyethyl)-5(6')-carboxyfluorescein acetomethyl ester. Switching from CO2/HCO3- -buffered to HEPES-buffered solution caused a rapid intracellular alkalinization followed by a counter-regulation towards initial pH(i). The recovery of pH(i) was dependent upon extracellular chloride, but independent of extracellular sodium. Adding 500 microM H2DIDS significantly reduced the increase of pH(i). For further characterization of the bicarbonate exporting systems, we tested the ability to reverse the direction from HCO3- export to import in the absence of sodium and chloride. Under sodium and chloride-free conditions, counter-regulation after CO2-induced pH(i) decrease did not differ from pH(i) recovery in the presence of sodium and chloride. Existence of bicarbonate exporting systems in cultured ruminal epithelial cells and intact ruminal epithelium was verified by reverse transcription polymerase chain reaction (RT-PCR). Using RT-PCR and subsequent sequencing, expression of mRNA encoding for AE2, DRA and PAT1 could be found. Bicarbonate exporting systems could therefore be detected both on the functional and structural level.

Animals↗