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PubMed2002

Position of the abomasum in dairy cows during the first six weeks after calving.

The position of the abomasum in six cows was examined by ultrasonography at regular intervals for six weeks after they had calved. Its position was established by determining the distance between the margin of the left side of the abomasum and the ventral midline at two sites. During the last weeks of pregnancy, the abomasum was positioned in a small region of the left ventral side of the abdominal cavity. At parturition it was positioned high on the left side and then descended. The abomasum was furthest from the midline immediately after parturition. Its position was related to the interval after calving, the cow's feed intake, and the pH and osmotic pressure of the rumen fluid. There was considerable variation between the cows in the position of the abomasum, which was in part due to analytical variation, and in individual cows it had a circadian rhythm.

Abomasum↗
PubMed1997

Nutritional risk factors in the etiology of left displaced abomasum in dairy cows: a review.

The transition period occurring 2 wk prepartum through 2 to 4 wk postpartum is the major risk period in the etiology of left displaced abomasum. The prepartum depression of intake and the slow postpartum increase in intake are risk factors causing lower ruminal fill, reduced forage to concentrate ratio, and increased incidence of other postpartum disorders. Uncomplicated ketosis, retained placenta, metritis, and hypocalcemia at parturition are risk factors for left displaced abomasum. Excessive amounts of concentrate during the prepartum period increase the risk of left displaced abomasum, which may occur from the lower ruminal fill caused by greater prepartum intake depression and reduced forage to concentrate ratio, decreased ruminal motility from lower ruminal fill and higher volatile fatty acid concentration, and decreased abomasal motility and emptying from higher concentrations of volatile fatty acids. Effects of volatile fatty acids on motility may be exacerbated by low ruminal absorption of volatile fatty acids during the transition period. Minimal intake of concentrate during the prepartum period may increase the risk of left displaced abomasum through failure to increase the absorptive capacity of the ruminal papillae and failure of the microbial population of the rumen to adapt prior to the intake of high energy postpartum diets. Increased risk of left displaced abomasum in cows that are hypocalcemic at parturition may be due to decreased ruminal and abomasal motility.

Abomasum↗
PubMedDate not supplied

Nervous regulation of abomasum motor activity in sheep.

Pharmacological studies of abomasum motor activity were carried out in 3 sheep with chronic fistulae in the rumen and the fundus and pyloric part of the abomasum. The contractions of these parts of the stomach were recorded by the balloon method. The obtained results showed that in the abomasum stimulation of alpha-adrenergic receptors raises the degree of motor activity while stimulation of beta-adrenergic receptors inhibits it. It has been shown also that the sympathetic system has a greater influence through the beta-adrenergic receptors on the motor activity of the pyloric part than on that of the fundus of the abomasum. The analysis of the records obtained after bilateral vagotomy demonstrated that the automatism of the pyloric part was greater than that of the fundus of the abomasum.

Abomasum↗
PubMed1995

Maturational effects of cortisol on the exocrine abomasum and pancreas in fetal sheep.

The role of cortisol in the prenatal development of digestive enzymes in the abomasum (prochymosin and pepsinogen) and pancreas (amylase, trypsin, chymotrypsin) has been investigated in the fetal lamb during late gestation. The abomasum and pancreas were collected from 22 unoperated control fetuses (99-145 days gestation; term, 145 +/- 2 days), from seven pairs of twins infused with either saline or cortisol for five days preceding delivery at 127-133 days, and from four 139-143-day-old fetuses adrenalectomized at 120-123 days. Developmental increases (2-8-fold) occurred in protease concentrations in the fetal abomasum and in amylase and chymotrypsin contents in the fetal pancreas. These increases paralleled the normal prepartum rise in fetal plasma cortisol. In addition, the enzyme values were significantly higher in cortisol-infused than in saline-infused fetuses (with the exception of pancreatic amylase) and were significantly lower in adrenalectomized fetuses than in control fetuses at term. The pH of abomasal fluid remained neutral (pH 6.8-8.0) during late gestation and was not affected by cortisol treatment or adrenalectomy. The results suggest that cortisol stimulates the development of the exocrine abomasum and pancreas in fetal sheep and may, thereby, increase the digestive capacity in neonatal lambs. Compared with the pig, another long-gestation species, the sheep has an early development of gastric pepsinogen but a late development of gastric acidity and pancreatic protease activities.

Abomasum↗
PubMed2000

Partitioning of amino acids flowing to the abomasum into feed, bacterial, protozoal, and endogenous fractions.

We partitioned the flow of amino acids (AA) to the abomasum among rumen undegradable protein (RUP) and bacterial, protozoal, and endogenous fractions using four Holstein cows in midlactation that were equipped with ruminal and abomasal cannulas. A 2 x 2 factorial design with four diets, combinations of high or low ruminally degradable organic matter, and rumen degradable protein, was employed. Crude protein (CP) and AA contents of ruminal bacteria and protozoa and abomasal digesta were determined. Equations for the source compositions and in vivo flows of CP and 16 AA were then solved simultaneously with a linear program to estimate the contribution of RUP, bacterial, protozoal, and endogenous CP to AA flows. The flows of RUP and bacterial AA were not affected by diet. Low dietary RDP increased the flow of protozoal AA to the abomasum, but the ruminally degradable organic matter content of the diet did not affect protozoal AA flow. Across diets, RUP, bacterial, protozoal, and endogenous fractions provided 55, 33, 11, and <1% of the CP, and 62, 26, 12, and <1% of the AA that reached the abomasum. The linear program was a useful tool for partitioning AA that flows to the abomasum. The technique may also allow dietary effects on ruminal microbes and the AA profile of protein flowing to the duodenum to be better understood and perhaps manipulated.

Abomasum↗
PubMed1998

Dry cow diet, management, and energy balance as risk factors for displaced abomasum in high producing dairy herds.

The objective of this study was to determine prepartum risk factors for displaced abomasum. The design was a prospective study of 1170 multiparous Holstein cows from 67 high producing dairy herds in Michigan. Each farm was visited four times within a 6-wk period. At each visit, data on nutrition and management were collected. All multiparous cows within 35 d of projected calving were assigned a body condition score, and blood was sampled to determine the concentration of nonesterified fatty acids in plasma. A multivariable linear regression model was used to determine risk factors associated with the incidence of displaced abomasum during lactation on a herd basis. A multivariable logistic regression model with random effect was used to determine risk factors for displaced abomasum on an individual cow basis. Significant risk factors for displaced abomasum included a negative energy balance prepartum (as estimated from plasma nonesterified fatty acids), a high body condition score, suboptimal feed bunk management prepartum, prepartum diets containing > 1.65 Mcal of net energy for lactation/kg of dry matter, winter and summer seasons, high genetic merit, and low parity.

Abomasum↗
PubMed1985

Histological development of bovine abomasum.

The histological development of the bovine abomasum during fetal and neonatal periods was studied. The abomasum in a fetus of 2.3 cm in length (estimated to be 1 month old) was a separated compartment situated to be caudo-ventral to the primordium on the median plane. On the later stages, the primitive stomach became distinctly separated into rumen, reticulum, omasum and abomasum. The epithelium of abomasum was pseudostratified histologically, consisting of cells low differentiation. The stomach in a fetus of 13-14 cm in length (estimated to be 3 months old) displayed the morphological feature with nearly same proportion as an adult stomach. In this stage, abomasal epithelium had a shape of simple column and also formed gastric pits. Pyloric gland cells could be recognized earliest of all the gastric exocrine cells in fetuses of 16-18 cm in length (estimated to be 3-4 months old). Mucous neck cells could be found in fetuses 43-45 cm in length (estimated to be 5-6 months old). Pyloric gland cell and mucous neck cell contained neutral and sialo- or sulfo mucosubstances in neonates. Chief cells, could be noticed in fetuses 58-65 cm in length (estimated to be 6-7 months old), and were devoid of demonstrable mucosubstance as well as parietal cells. Main abomasal gland cells began to develop to increase rapidly in number in the latter half period of gestation. All the types of gastric cells became to be present and mature in form at birth.

Abomasum↗
PubMedDate not supplied

Motor activity of the abomasum in sheep.

The experiments were carried out on 5 sheep with chronic fistulae of the rumen and of the fundus and pyloric part of the abomasum. The motor activity of the parts of the stomach containing fistulae was recorded by the balloon method. The analysis of the obtained contraction curves showed that the motor activity of the pyloric part was more intense than that of the fundus of the abomasum, and the intensity increased with filling of the multichamber stomach with food, food intake increased the tonus and the intensity of peristaltic movements in the fundus and pyloric part of the abomasum, rumination had no effect on the motor activity of the fundus but increased usually the frequency of contractions of the pyloric part. It has been demonstrated also that the movements of the pyloric part of the abomasum can be inhibited for short time periods.

Abomasum↗
PubMed1980

Torsion of the abomasum in ruminants: diagrammatic representation of rotary movements based on post-mortem findings.

A theoretical analysis of the types of displacement of the abomasum in the abdomen is presented based on a study of forty-seven post-mortem examinations of calves, cows, lambs and sheep showing right-sided abomasal displacement and production of knots. These displacements are quantified following the introduction of a dual-axial system. One system (XYZ) related to displacements of the abomasum on a pendulum model, the point of suspension being situated on the visceral surface of the liver and the arms consisting of parts of the digestive tract adjacent to the abomasum. The other system (x1y1z1) comprises axes centered on the abomasum, about which this organ was able to rotate without changing its position in the abdomen. In order to make quantification of the displacements and deformations possible, the term twine is introduced. Twining results from interlacing of sections of the digestive tract, which are not normally adjacent. This limits the concept of torsion to helices appearing in the pyloro-duodenal region and the omaso-abomasal junction. To identify the various forms of abomasal displacement, a new terminology is introduced and basic elements suggested to make quantifications possible.

Abomasum↗
PubMed1997

[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.

Abomasum↗
PubMed2006

Estimation of abomasum strongyle nematode infections in sheep at necropsy: tentative proposals for a simplified technique.

Several necropsy techniques are available for estimating the abundance of gastro-intestinal nematodes in abomasum of ruminants. Standardization of techniques is needed to allow accurate comparisons between laboratories. Here we propose a standardized technique for estimating the abundance of worms. We intend to compare the worms' number estimations in lambs and ewes based on contents and washings, to determine the uniformity of worm counts in aliquots, and to estimate the total worm number from washings. The digesta (or "contents") and the washings of the abomasum are treated separately. The worms of each subsample are diluted with water and the total number of worms is estimated on a small volume (aliquots) of these subsamples. The use of aliquots assumes that the worms are uniformly distributed in the whole volume of each subsample. We first confirmed that the use of aliquots is appropriate in most cases. We then show that the use of the washings alone allows a faster and a suitable estimation of the total worm burden for all strongyle species of the abomasum in both ewes and lambs. The evaluation of our necropsy procedure is a first step to a standardized technique which should be improved by validation in other laboratories.

Abomasum↗
PubMed2000

Cooperia pectinata and C. punctata, parasites of the abomasum of cattle in northern Cameroon (Central Africa).

Cooperia pectinata Ransom, 1907 and C. punctata von Linstow, 1907 are common trichostrongyles of zebu cattle in Africa. Their intestinal localization within the digestive tract is considered by many authors to be exclusive. Nevertheless, some limited surveys in Malagasy, Mauritania, The Gambia and Cameroon reported the presence of both Cooperia species in the abomasum. The present survey was carried out in a slaughterhouse of northern Cameroon on 17 zebu cattle and confirms the infection of the small intestine and the abomasum by the two species within the total number of cattle examined. Abomasal infections especially with Cooperia punctata were heavier than those in the intestine. Due to the movements of herdbreeders in Central Africa, and to the preliminary results obtained in Mauritania, The Gambia, Burkina Faso and Malagasy, abomasal localization of C. pectinata and C. punctata may be encountered in very large areas of Africa, and that cooperiosis may contribute together with Haemonchus species to the digestive disorders involving the abomasum.

Abattoirs↗
PubMed2001

Plasma growth hormone (GH) responses after administration of the peptidergic GH secretagogue KP102 into the oral cavity, rumen, abomasum and duodenum in adult goats.

The study was performed to determine whether orally administered KP102 (also known as GHRP-2) stimulates GH release in adult goats, and how the orally administered KP102 passes through the digestive tract and stimulates GH release in ruminant animals. Five mg/kg body weight (BW) of KP102 dissolved in 9 ml of saline were administered into the oral cavity, rumen, omasum and duodenum of adult goats, and GH release after administration of KP102 was examined. The GH levels were significantly elevated at 20 min after administration of KP102 into the oral cavity, and plasma concentrations of GH remained significantly elevated until 60 min (P < 0.05). The GH levels after administration of KP102 into the abomasum were variable. However, the GH level tended to increase within 30 min after administration, and were significantly higher than those of controls after 120 to 150 min (P < 0.05). The GH levels after administration of KP102 into the duodenum were significantly elevated at 40 min after administration, and plasma concentrations of GH remained significantly elevated until 140 min (P < 0.05). The administration of KP102 into the rumen failed to stimulate GH release. The GH response curves (AUC) produced after administration of KP102 into the abomasum or duodenum were 2.2-fold greater than those for after administration into the oral cavity (P < 0.05). The oral administration of 5 mg/kg BW of KP102 in the powder state, not dissolved in 9 ml of saline, failed to stimulate GH release. These results suggested that orally administered KP102 dissolved in saline transiently stimulates GH release in adult goats, and this phenomenon might be due to small amounts of the peptides entering directly into the abomasum with liquid bypassing the rumen.

Abomasum↗
PubMed1998

In vitro motility disorders associated with displaced abomasum in dairy cows.

The objective of this study was to investigate in vitro abomasal motility in dairy cows diagnosed with displaced abomasum. Longitudinal muscle myenteric plexus preparations originating from the abomasal antrum of control cows, and cows diagnosed with left displaced abomasum (LDA), right displaced abomasum (RDA) or abomasal volvulus (AV) were used. In control preparations electrical field stimulation evoked an immediate cholinergic contractile response exceeding amplitude of basal contractions by 60%. In contrast, contractile activity was significantly inhibited during electrical stimulation in LDA, RDA and AV by 47%, 66% and 45%, respectively. This inhibition was reversed in the presence of L-NAME. The staining intensity of NADPH-positive myenteric neurones was significantly higher in displaced abomasa than in controls. Concentration-response curves indicated that preparations from displaced abomasa showed reduced sensitivity to acetylcholine. This study demonstrated motility disorders in displaced abomasa in vitro. The results suggested that abomasal displacement is associated with malfunctions at the level of the intrinsic nervous system combined with impaired cholinergic muscle responses. There appeared to be a predominance of nitrergic inhibitory mechanisms over excitatory mechanisms. These results might be of significance for diseases associated with gastric hypomotility and emptying disorders.

Abomasum↗
PubMed1985

Enzyme potentialities of the abomasum and pancreas of the calf. II. Effects of weaning and feeding a liquid supplement to ruminant animals.

Thirty-nine male Friesian calves, divided into three groups (L, S and SL), were reared until they were 147 to 175 days old. Group L calves remained preruminant until slaughter. Group S calves were weaned between 5 and 9 weeks of age and then received a concentrate feed and dehydrated fescue ad libitum. Besides this diet, group SL calves received a liquid supplement containing whey powder and soyabean oil meal, supplying a total of 940 g of dry matter and 5,060 g of water per day. The slaughter age of the calves in each group was chosen so that carcass weight in the three groups was similar. At slaughter, the abomasum and pancreas of each animal were collected and the gastric (chymosin and pepsin) and pancreatic (chymotrypsin, trypsin, lipase and amylase) enzymes were assayed. Weaning caused a decrease in the chymosin content and an increase in the pepsin content of the abomasum. The amount of chymosin per kg of carcass was on the average 2.8-fold lower and that of pepsin 1.9-fold higher in groups S and SL than in group L. The amount of pepsin tended to be higher in group S than in group SL, but only the difference observed (36%) for the total amount was significant. In group S, the pancreata showed more chymotrypsin, trypsin and amylase activities but less lipase activity than in group L; the observed differences in these activities per kg of carcass were 32, 49, 70 and 24%, respectively. The activities of group SL were lower than those of group L for trypsin, chymotrypsin and lipase but higher for amylase (17, 12, 44 and 18%, respectively). Group SL exhibited lower activities than group S (55, 67, 16 and 44%, respectively, for trypsin, chymotrypsin, lipase and amylase). Weaning appeared to induce large changes in abomasal and pancreatic enzyme potentialities which exhibited patterns similar to the variations in the amounts of substrate intake. In our experimental conditions, giving a liquid supplement to ruminant calves had a depressive effect on the activities of the enzymes (except chymosin), in the pancreas and the abomasum.

Abomasum↗
PubMedDate not supplied

Left displacement of the abomasum in dairy cattle: recent developments in epidemiological and etiological aspects.

The research with respect to displacement of the abomasum (DA) in dairy cattle is reviewed. Evaluated articles describe epidemiological and experimental studies. The occurrence is elevated with regard to breed, gender, age, concurrent diseases, environmental aspects and production levels as contributing factors and emphasis is placed on the effects of nutrition and metabolism. Reviewing the experimental work, distinction is made between the research into gas production in the abomasum and hypomotility of the abomasum, since both represent presumed pathways in the development of DA. Although the different fields of research have positive contributions to the understanding of the pathogenesis of DA, contradictions in the different studies are present. This is partly due to extrapolation of results from sheep to cows, or because of a low number of cows in the experiments. Finally, general suggestions are made for further research in the field of the pathogenesis of DA.

Abomasum↗
PubMed1983

Factors influencing the digestion of dietary carbohydrates between the mouth and abomasum of steers.

Six protozoa-free steers with simple rumen and abomasal cannulas were given basal diets consisting of a concentrate mixture of flaked maize and tapioca with either barley straw (BS) or alkali-treated barley straw (BSA). Other diets used were supplemented with urea (BSU and BSAU respectively) or contained fish meal in place of tapioca BSF and BSAF respectively). The diets were given in a 6 X 6 Latin square design. Diets were isoenergetic and provided sufficient metabolizable energy (ME) to support a growth rate of approximately 0.5 kg/d. Basal diets, urea- and fish-meal-supplemented diets had estimated rumen-degradable nitrogen (RDN):ME values (g/MJ) of 0.5, 1.2 and 0.8 respectively. 103Ruthenium and polyethylene glycol were given as flow markers, and flows (g/24 h) at the abomasum of organic matter (OM) and carbohydrate components were calculated. True digestibility coefficients of OM between mouth and abomasum were significantly greater for diets containing alkali-treated straw (approximately 0.63) than for those containing untreated straw (approximately 0.55) but were not significantly affected by N supplementation. Digestibility coefficients of the neutral-sugar components of dietary polysaccharides between mouth and abomasum were 0.28, 0.34, 0.31, 0.23, 0.31 and 0.87 for mannose, galactose arabinose, xylose, cellulose-glucose and starch-glucose respectively for diet BS. Corresponding values were 0.37, 0.42, 0.56, 0.51, 0.40 and 0.88 for diet BSA. All but the mannose and starch-glucose values were significantly greater for the latter diet. N supplementation also led to increases in digestibility of all neutral sugars except mannose and starch-glucose. Fish meal produced a markedly greater effect than urea but only significantly so for cellulose-glucose. Thus, the highest digestibilities were seen for diet BSAF and were 0.68, 0.67, 0.74 and 0.64 for galactose, arabinose, xylose and cellulose-glucose respectively. Of all these sugars xylose consistently showed the greatest response in digestibility to sodium hydroxide treatment or N supplementation.

Abomasum↗