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ABSTRACT: Uterine torsion is a twisting of the uterus or uterine horn perpendicular to its long axis. We report a case of uterine torsion in an adult breeding Sprague Dawley rat. The rat died a month after her last recorded delivery. Post mortem examination of the rat revealed 270 degrees torsion of the right uterine horn. The uterus contained a single foetus. The liver was pale and enlarged. The rest of the viscera appeared normal. Histopathological examination showed acute hepatic necrosis and pulmonary congestion with mild lymphocytic infiltrates peribronchially. The acute hepatic necrosis may have been associated with septicaemia due to compromised blood vessels following the uterine torsion. The presence of a single foetus could have resulted in foeto-maternal disproportion with resultant uterine torsion. Torsion of the uterus can be accompanied by haemostatic and metabolic complications, which could have caused the death of the rat. Although uterine torsion is a rare condition in rats, it should be considered as a potential complication of gestation in animal breeding units.
Journal of the South African Veterinary Association 09/2011; 82(3):183-4.
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ABSTRACT: We report, for the first time, an incidental finding of Calodium hepaticum infestation in a sub-adult female Cape ground squirrel (Xerus inaurus). Post mortem examination of the squirrel revealed severe haemoperitoneum, splenomegaly and hepatomegaly with miliary white spots distributed diffusely throughout the hepatic parenchyma. Histologically the portal tracts in the liver showed granulomatous inflammation with fibrosis and numerous giant cells. Occasional adult worms were identified and there were multiple C. hepaticum eggs distributed diffusely throughout the portal tracts and the parenchyma. The spleen also contained C. hepaticum eggs. The genus Rattus is the primary host and reservoir of C. hepaticum, but C. hepaticum infections have been reported previously in other Sciuridae. Based on our findings, people should be cautious of the zoonotic potential of C. hepaticum, when they come into contact with the Cape ground squirrel.
Journal of the South African Veterinary Association 12/2009; 80(4):276-7.
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ABSTRACT: Conventionally, the management of exocrine pancreatic insufficiency (EPI) involves the consumption of a specific diet as well as the replacement of pancreatic enzymes, the effectiveness of which is usually measured by a classical method of blood analyses of non-esterified fatty acids (NEFA) and triglycerides (TG). Dietary supplementation with a pancreatic enzyme preparation (PEP), in conjunction with a high-fat diet, on growth performance, digestibility and absorption (analysed using turbidimetry) of dietary fat in pigs with EPI was investigated.
EPI was developed by surgical ligation of the pancreatic duct of six male pigs, 6 weeks of age. The pigs were fed a high fat diet (twice daily). A PEP containing 1800 mg entero-coated pancreatin was included in the high fat meals. Blood, urine and faecal samples were collected. The urine and faeces were analysed for dry matter, crude protein and fat content. The lipaemic index and plasma lipid profiles were assessed.
EPI completely stopped growth of the pigs. Treatment with PEP significantly increased (P<0.05) growth and body mass as well as the digestibility of dry matter and crude protein. PEP significantly improved the co-efficient of fat absorption, the lipaemic index (measured by turbidimetry methods) and caused significant changes in plasma nonesterified fatty acids and triglyceride concentrations.
The short term enzymatic replacement therapy together with a high fat meal has immediate beneficial effects on diet digestibility and on the growth retardation observed in EPI pigs. The turbidimetry method used to measure lipaemic index is a reliable, quick and efficient technique in measuring plasma lipid profiles and thus a good tool for assessing fat absorption.
Advances in Medical Sciences 01/2009; 54(1):7-13.
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ABSTRACT: The litter from six Sprague-Dawley rats was used to study the short-term effects of African potato (AP) corm extracts in suckling rats. Ten days after birth, the pups in each litter were assigned to treatment groups and received alcohol (AL) or aqueous (AQ) extracts of AP (50 mg kg(-1) b.w. in 0.9% saline, 10 ml kg(-1) b.w., and a high dose 200 mg kg(-1) b.w. in 0.9% saline, 10 ml kg(-1) b.w.) via a stomach tube, for 5 consecutive days. A fifth group (control) received 0.9% saline (10 ml kg(-1) b.w.). Between gavage, the pups were kept with their dams. The pups were then killed and the viscera removed for gross and microscopic morphometric measurements. The low dose of AQ and AL extracts of AP significantly increased (P<0.01, ANOVA) the mean weight gain. The high dose of AQ significantly increased (P<0.05, ANOVA) the weight of the caeca whilst the low dose of the AL extract reduced pancreas weight compared to the control and low dose AQ groups. All other morphometric parameters of the viscera measured did not differ significantly between the groups. The small intestinal villi and crypts did not reveal any signs of pathology.
Food and Chemical Toxicology 01/2008; 46(1):136-9. · 3.00 Impact Factor
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ABSTRACT: Presented is an African giant rat (Cricetomys gambianus) following zinc ingestion. The sick rat was lethargic, withdrawn, had soft, mucus-impregnated faeces and diahorrea, foot twitching and icterus. Comparative age, sex and body weight (b.wt.)-matched analyses were made with a healthy giant rat. Twelve-hourly Urine volume (UV), Haematocrit (Hct), urinary glucose, plasma zinc and Alkaline Phosphatase (ALP) were performed over an 8-week period. Full blood counts were performed and differential WBC counts and microscopic observations were made on blood smears obtained from both healthy and sick rats. Consecutive blood samples were drawn at the end of each week (Weeks <2-6 treatment; Weeks 7-8 post-treatment). Treatment involved oral vitamin B12 supplement at 4 microg/day and 2 ml diethylenetriaminepentaacetic acid (DTPA) intramuscular injections at 1 ml/450g b.wt./5 wks (Week 2 - 6). Day 1 showed neutropaenia, Heinz bodies on RBCs (reticulocytes and immature forms). Zinc (Day 1 - end Week 7), glucose (Day 1 - end Week 4), ALP (Day 1 -Week 4) and UV were elevated (Day 1 - end Week 6). Indications of moderate zinc toxicosis following ingestion and stress-associated glucosuria were concluded.
Journal of the South African Veterinary Association 10/2007; 78(3):163-5.
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ABSTRACT: Introduction Cowpea (Vigna unguiculata) is a valuable protein source that can contribute towards overcoming a predicted protein deficit equivalent to more than 1 000 000 t oilcake in Southern Africa by the year 2000 (Nell et al. 1992). However, like most other legumes, cowpeas contain antinutritional factors (ANFs) (Makinde et al. 1996). It has also been shown that feeding raw cowpea causes reduced growth and histomorphometric changes in the various segments of the intestine (Makinde et al. 1997) attributable to ANFs. The major ANFs in the cowpea are trypsin inhibitors, tannins and phytates (Aletor and Aladetimi 1989). Although the protease inhibitors are found in most legumes, only soybean inhibitors have been thoroughly investigated (Liener and Kakade 1980), and trypsin inhibitors in other legumes have received little attention.
J Anim Physiol a Anim Nutr 08/2007; 82(2‐3):57 - 65. · 0.86 Impact Factor
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ABSTRACT: Two antisecretory factor (AF)-derived peptides have been studied in relation to effects on motility of guinea pig colon. Colon segments were isolated from adult guinea pigs and incubated in Tyrode Ringer. Motility was measured as the force and frequency of contractions upon addition of the derived peptides AF 1 (8 amino acids (aa)) and AF 3 (10 amino acids). At the lowest concentration (5 pM), peptide AF 1 induced a negative effect on the force of contraction in colon segments; an effect that was abolished by the cholinergic agonist carbachol. Peptide AF 3 induced a significant increase in the force of colon contractions at all concentrations (5-180 pM), with carbachol only reducing the effect of peptide AF 3 at a concentration of 15 pM. Both peptides increased contractile frequency, although the overall response was lower for peptide AF 3 than for peptide AF 1. It is concluded that antisecretory factor-derived peptides may play a role in regulating colon motility such that under pathophysiological conditions, they may serve to hasten the evacuation of noxious agents from the large intestine.
Comparative Biochemistry and Physiology - Part A Molecular & Integrative Physiology 11/2004; 139(2):143-8. · 2.23 Impact Factor
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ABSTRACT: The gastrointestinal tract (GI tract), which extracts nutrients, electrolytes, minerals, and water, is prone to injury as a result of oral drug administration. Clinical assessment of the GI tract is often limited to measurements of transit time and observations of vomiting or diarrhoea, despite the existence of methods and techniques capable of assessing specific changes in GI function at the membrane, cell, and whole animal levels. Membrane studies, record the uptake of solutes, and electrolyte transport, assessing the affects of compounds on transepithelial GI transport and flux. Such methods lend themselves to permeability, immunohistochemistry, morphology, and molecular biology techniques. Isolated cells from the GI tract or cultured cell lines provide knowledge of regulation and function at a cellular level, whilst motility patterns, taken in vivo or from biopsies, provide information at a more integrated level. In anesthetised animals, ligated segments of the intestine can be infused with test compounds, providing information about absorptive and secretory processes important for the treatment of diarrhoea. Computer simulations and modelling are used to predict the disposition of a chemical and its metabolite and can, to some extent, replace animal testing, thereby reducing development costs. Indeed, software programs can be used to simulate the dissolution, absorption, distribution, metabolism, and excretion (ADME) properties of potential drugs in the human GI tract. Finally, advances in the field of imaging, combined with endoscopy, have resulted in a wireless capsule, allowing the inspection of the GI tract anatomy and pathology without surgical intervention. It is concluded that the field of safety pharmacology could rapidly, cheaply, and routinely incorporate membrane, isolated tissue, and endoscopy techniques for GI tract testing of drugs.
Journal of pharmacological and toxicological methods 01/2004; · 2.32 Impact Factor
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ABSTRACT: The ostrich is unique among birds in having complete separation of urine and faeces. The coprodeal epithelium is thus during dehydration exposed to a fluid 500 mOsm hyperosmotic to plasma. We have investigated whether the coprodeum is adapted like a mammalian bladder. The coprodeal epithelium was studied by electrophysiology in the Ussing chamber, and the anatomy by light microscopy and scanning electron microscopy. ELECTROPHYSIOLOGY: The short-circuit current (SCC) and open circuit electrical potential difference were recorded. The change induced by 0.1 mmol mucosal amiloride was recorded. An average basal SCC of 162+/-29 microA/cm(2) was observed, and a resistance of 297+/-34 Omega cm(2) calculated. These values are as observed in other avian coprodea. The resistance is much lower than in mammalian bladders (10000 Omega cm(2)). The amiloride-sensitive SCC, equal to net sodium absorption, was approximately 5 micromol/cm(2)h as observed in other avian species. ANATOMY: The mucosal membrane is composed of broad irregular folds with very short intestinal glands containing an unusually high proportion of goblet cells. CONCLUSION: The ostrich coprodeum is not adapted like a mammalian bladder. The abundance of goblet cells results in a copious secretion of mucus that establishes a thick unstirred layer giving effective osmotic protection.
Comparative Biochemistry and Physiology - Part A Molecular & Integrative Physiology 05/2003; 134(4):749-55. · 2.23 Impact Factor
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ABSTRACT: Tropical grain legumes represent potentially important feed for farm animals. However, diarrhoea and poor growth performance have been reported, due to the various anti-nutritional factors they contain. This study addressed in particular whether dietary cowpea impaired the growth of pigs, whether the small intestinal Na+/D-glucose coabsorptive transport capacity was decreased, whether the Cl- secretory capacity was increased, and, finally, whether these parameters were affected by heat treatment of cowpea. Pigs, 4 weeks old, were fed for 3 weeks with one of three diets: (i) standard soy, (ii) 75% of soy substituted with raw cowpea, or (iii) 75% of soy substituted with heat-treated cowpea. The absorptive and secretory capacities of the jejunum and ileum were measured with the Ussing chamber technique. Weight gain, feed intake, pancreatic protein and enzyme concentrations and levels of the blood hormones glucagon and cholecystokinin were also measured. The Na+ transport capacity was measured as the increase in short-circuit current (Isc) when D-glucose was added to the luminal side in the Ussing chambers. Isc was significantly higher in the jejunum from raw cowpea-fed pigs than in the jejunum from standard soy-fed pigs, with no difference between the two cowpea-fed groups. The phosphodiesterase inhibitor theophylline was subsequently added bilaterally, and the increase in Isc indicated the cAMP-depedent Cl- secretory capacity. In the jejunum this was significantly higher in raw and heat-treated cowpea-fed pigs than in standard soy-fed pigs. In contrast, there were no differences in the ileal transport capacities. There were no differences in the pancreatic protein and trypsin concentrations or the blood hormones, but the raw cowpea-fed pigs had significantly lower pancreatic amylase than standard soy-fed pigs. Weight gain and feed intake were lowest in the cowpea-fed groups, with no significant difference between the two groups. In conclusion, the hypothesis of impaired small intestinal absorption of D-glucose and Na+ as causing malabsorption, and therefore impaired growth, during cowpea substitution in the feed may be firmly rejected. The increased Cl- secretory capacity, although moderate, may contribute to the higher incidence of post-weaning diarrhoea in cowpea-fed pigs, as observed in other studies. Additionally, the decreased food intake, feed conversion and weight gain were unaffected by heat treatment, further suggesting involvement of heat-stable anti-nutritional factors.
Zentralblatt für Veterinärmedizin. Reihe A 01/2000; 46(10):581-92.
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ABSTRACT: Vasoactive intestinal polypeptide is a transmitter at the neuroepithelial junction of the small intestine in cholera toxin-induced secretion. We investigated whether the secretory effect in vitro of vasoactive intestinal polypeptide in porcine jejunum was changed with age. Stripped tissue preparations from three age groups, neonatal (7-11 days), young (6-8 weeks) and adult (13-15 weeks) pigs, were mounted in Ussing chambers and short-circuited. Vasoactive intestinal polypeptide produced concentration dependent increases in short-circuit current in all three age groups with EC50 values (in nM) of 14.5 +/- 1.9, 16.2 +/- 2.0 and 147 +/- 0 in neonatal, young and adult pigs, respectively. The peak increases in short-circuit current in adult pigs were significantly decreased compared with the other two age groups. To evaluate the secretory capacity, theophylline was added to tissue preparations in which baseline short-circuit current again was established. Theophylline caused a significantly lesser increase in short-circuit current in adult pigs (25.4 +/- 2.0 microA.cm-2) than neonatal (57.1 +/- 3.6 microA.cm-2) and young pigs (63.1 +/- 2.9 microA.cm-2). In conclusion, vasoactive intestinal polypeptide showed a marked decrease in the secretory response with age in porcine jejunum, at least partly caused by a reduced secretory capacity of the enterocytes.
Comparative Biochemistry and Physiology - Part A Molecular & Integrative Physiology 10/1999; 124(1):29-33. · 2.23 Impact Factor
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ABSTRACT: Two antisecretory factor (AF)-derived peptides have been studied in relation to effects on motility of guinea pig colon. Colon segments were isolated from adult guinea pigs and incubated in Tyrode Ringer. Motility was measured as the force and frequency of contractions upon addition of the derived peptides AF 1 (8 amino acids (aa)) and AF 3 (10 amino acids). At the lowest concentration (5 pM), peptide AF 1 induced a negative effect on the force of contraction in colon segments; an effect that was abolished by the cholinergic agonist carbachol. Peptide AF 3 induced a significant increase in the force of colon contractions at all concentrations (5–180 pM), with carbachol only reducing the effect of peptide AF 3 at a concentration of 15 pM. Both peptides increased contractile frequency, although the overall response was lower for peptide AF 3 than for peptide AF 1. It is concluded that antisecretory factor-derived peptides may play a role in regulating colon motility such that under pathophysiological conditions, they may serve to hasten the evacuation of noxious agents from the large intestine.
Comparative Biochemistry and Physiology - Part A: Molecular & Integrative Physiology.
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ABSTRACT: The gastrointestinal tract (GI tract), which extracts nutrients, electrolytes, minerals, and water, is prone to injury as a result of oral drug administration. Clinical assessment of the GI tract is often limited to measurements of transit time and observations of vomiting or diarrhoea, despite the existence of methods and techniques capable of assessing specific changes in GI function at the membrane, cell, and whole animal levels. Membrane studies, record the uptake of solutes, and electrolyte transport, assessing the affects of compounds on transepithelial GI transport and flux. Such methods lend themselves to permeability, immunohistochemistry, morphology, and molecular biology techniques. Isolated cells from the GI tract or cultured cell lines provide knowledge of regulation and function at a cellular level, whilst motility patterns, taken in vivo or from biopsies, provide information at a more integrated level. In anesthetised animals, ligated segments of the intestine can be infused with test compounds, providing information about absorptive and secretory processes important for the treatment of diarrhoea. Computer simulations and modelling are used to predict the disposition of a chemical and its metabolite and can, to some extent, replace animal testing, thereby reducing development costs. Indeed, software programs can be used to simulate the dissolution, absorption, distribution, metabolism, and excretion (ADME) properties of potential drugs in the human GI tract. Finally, advances in the field of imaging, combined with endoscopy, have resulted in a wireless capsule, allowing the inspection of the GI tract anatomy and pathology without surgical intervention. It is concluded that the field of safety pharmacology could rapidly, cheaply, and routinely incorporate membrane, isolated tissue, and endoscopy techniques for GI tract testing of drugs.
Journal of Pharmacological and Toxicological Methods 49(3):187-99. · 2.32 Impact Factor
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ABSTRACT: The ostrich is unique among birds in having complete separation of urine and faeces. The coprodeal epithelium is thus during dehydration exposed to a fluid 500 mOsm hyperosmotic to plasma. We have investigated whether the coprodeum is adapted like a mammalian bladder. The coprodeal epithelium was studied by electrophysiology in the Ussing chamber, and the anatomy by light microscopy and scanning electron microscopy. Electrophysiology: The short-circuit current (SCC) and open circuit electrical potential difference were recorded. The change induced by 0.1 mmol mucosal amiloride was recorded. An average basal SCC of 162±29 μA/cm2 was observed, and a resistance of 297±34 Ω cm2 calculated. These values are as observed in other avian coprodea. The resistance is much lower than in mammalian bladders (10 000 Ω cm2). The amiloride-sensitive SCC, equal to net sodium absorption, was approximately 5 μmol/cm2 h as observed in other avian species. Anatomy: The mucosal membrane is composed of broad irregular folds with very short intestinal glands containing an unusually high proportion of goblet cells. Conclusion: The ostrich coprodeum is not adapted like a mammalian bladder. The abundance of goblet cells results in a copious secretion of mucus that establishes a thick unstirred layer giving effective osmotic protection.
Comparative Biochemistry and Physiology - Part A: Molecular & Integrative Physiology.
