Nephrotoxicity and hepatotoxicity in calves apparently caused by experimental feeding withNarthecium ossifragum

Seven calves were fed a mixture of bog plants containing 15 g (wet matter)Narthecium ossifragum per kg live weight for two consecutive days. Their serum creatinine, urea and magnesium concentrations increased, whereas the serum calcium concentration decreased. Histopathological examination of the kidneys of the 5 calves that were killed revealed tubular epithelial cell degeneration and necrosis. There were signs of liver dysfunction in all the calves including increased aspartate aminotransferase (ASAT), glutamate dehydrogenase (GLDH) and -glutamyltransferase activities.All the calves refused to ingestN. ossifragum after 2 days feeding, and their appetite for hay and concentrate was also reduced. It can be concluded thatN. ossifragum is nephrotoxic and hepatotoxic to calves.Abbreviations ALP alkaline phosphatase - ASAT aspartate aminotransferase - -HBA -hydroxybutyric acid - CK creatine kinase - d.m. dry matter - -GT -glutamyltransferase - GFR glomerular filtration rate - GLDH glutamate dehydrogenase - MCV mean cell volume - RBC red blood cells - SEM standard error of the mean - WBC white blood cells - w.m. wet matter     

Tolerance to the Nephrotoxic Component of Narthecium ossifragum in Sheep: The Effects of Repeated Oral Doses of Plant Extracts

Young adult sheep were dosed with extracts of Narthecium ossifragum plants by the oral or parenteral routes and the resulting nephrotoxicity was assessed from the increases in the concentrations of creatinine and urea in the serum. Following single intraruminal or intraperitoneal doses of extracts derived from 30 g N. ossifragum (wet weight) per kg live weight (kg lw), serum creatinine concentrations increased from about 100 mol/L to between 260 and 510 mol/L. The serum urea concentrations increased from about 5–8 mmol/L to between 11 and 66 mmol/L in individual sheep. Daily intraruminal administration of 5–30 g/kg lw to three sheep over a 10- or 15-day period increased creatinine concentrations from 100 mol/L to 300–760 mol/L, and urea concentrations from 5–8 mmol/L to 35 mmol/L. A single intraperitoneal challenge dose of 30 g/kg lw, delivered 7 or 12 days after the final intraruminal dose, did not lead to increased serum creatinine or urea concentrations, indicating that oral treatment had apparently resulted in an increased tolerance to the nephrotoxic principle(s) in N. ossifragum.     

The effect of transfer factor treatment on two challenge infections ofHaemonchus contortus in immuno-competent 7-month-old lambs

A number of immuno-competent Blackface lambs were infected with 10,000Haemonchus contortus third stage larvae and were later challenged with a second dose of 10,000H. contortus third stage larvae. One group of lambs was treated with dialysed transfer factor prior to the second challenge dose.Histological changes in the abomasal wall, reductions in abomasal worm burdens at slaughter and faecal egg counts monitored throughout the experiment suggested the presence in some animals of (1) an innate resistance, (2) a self curing effect, (3) an enhancement of this self curing effect in the transfer factor treated group and (4) a response in one transfer factor treated animal comparable to classical self cure.     

Plasma,Urinary and Biliary Residues in Cattle Following Intramuscular Injection of Nortestosterone Laurate

The synthetic androgen 19-nortestosterone (-NT) has been used illegally as a growth promoter in cattle production in the European Union. Elimination of -NT and its metabolites in plasma, urine and bile was studied in three cattle with cannulated gallbladders following intramuscular injection at a single site of 500 mg of the laurate ester (NTL) containing 300.5 mg -NT. Using enzyme immunoassay quantification, plasma Cmax of free -NT was 0.5±0.15 g/L (mean±SEM). Concentrations of free -NT in plasma were consistently greater than the assay limit of quantification (0.12 g/L) for 32.7±13.42 days. Mean residence time for free -NT in plasma was 68.5±20.75 days. Following sample preparation by immunoaffinity chromatography, high-resolution GC-MS was used to quantify -NT and -NT in urine and bile. -NT was detected irregularly in urine from two of the three animals post injection. The principal metabolite present in the urine, -NT, was detected for 160.3±22.67 days post injection. Cmax for -NT in urine was 13.7±5.14 g/L. Mean urinary AUC0–183 days for -NT was 845.7±400.90 (g h)/L.In bile, -NT was the only metabolite detected for 174.3±8.67 days post treatment. Cmax for -NT in bile was 40.8±12.70 g/L and mean biliary AUC0–183 days for -NT was 1982.6±373.81 (g h)/L. Concentrations of -NT in bile samples were greater than those in urine samples taken at the same time. The mean ratio of biliary:urinary AUC0–183 days was 3.0±0.72. It is concluded that bile is a superior fluid for detection of -NT following injection of NTL, owing to the longer period during which residues may be detected after administration.     

The use of cultured hepatocytes from goats and cattle to investigate xenobiotic oxidative metabolism

The oxidative metabolism of aldicarb (ALD), a carbamate pesticide, and fenbendazole (FBZ), an anthelmintic, was studied using cultured hepatocytes obtained from 4 goats and a bullock and incubated with ALD (50 mol/L) and FBZ (10 mol/L). The parent compounds and the metabolites were measured by HPLC. Both compounds are metabolized at the sulphur atom via two sequential oxidations, first to the sulphoxide (aldicarb sulphoxide and oxfendazole, respectively) and then to the sulphone. Oxfendazole and fenbendazole sulphone from FBZ, and aldicarb sulphoxide from ALD were found in both species. Aldicarb sulphone was not produced by the hepatocyte preparations from the bullock. The good correlation obtained comparing the in vitro results of FBZ metabolism with published in vivo dat obtained on FBZ kinetics in the same species confirmed the usefulness of in vitro models for predictive analysis of in vivo xenobiotic biotransformations.Abbreviations ALD aldicarb - ALDSON aldicarb sulphone - ALDSOX aldicarb sulphoxide - BSA bovine serum albumin - ID internal diameter - EGTA ethylene glycol bis(-aminoethyl ether) N,N,N,N-tetraacetic acid - FBZ fenbendazole - FBZSON fenbendazole sulphone - HBSS Hanks' balanced saline solution - HPLC high-pressure liquid chromatography - LDH lactate dehydrogenase - MFO mixed function oxidase - NCS newborn calf serum - OXF oxfendazole - WME Williams' Medium E     

Identification of Functional α-Adrenoceptor Subtypes in the Bovine Female Genital Tract During Different Phases of the Oestrous Cycle

The concentration and functionality of the -adrenoceptor (-AR) subtypes in the genital tract of cyclic heifers were investigated. In each tissue sample, a single class of ₁-ARs was observed, whereas two distinct classes of ₂-ARs were discriminated: low-affinity (LA) and high-affinity (HA) ₂-ARs. Statistical analysis showed the presence of significantly (p < 0.05) higher concentrations of all -AR subtypes in the follicle than in the corpus luteum. No significant differences were found in the ovary or myometrium between the luteal and follicular phases. In the ovary, the density of ₁-ARs was significantly (p < 0.05) higher than that of ₂-ARs. By contrast, there were significantly (p < 0.05) more ₂-ARs than ₁-ARs in the myometrium. As far as ₂-ARs are concerned, LA ₂-ARs were significantly (p < 0.05) higher than HA ₂-ARs in all tested tissues. Competition studies suggested that the rank order of potency of antagonists for ₁-ARs was prazosin > phentolamine > yohimbine, whereas for ₂-ARs the order of potency was yohimbine phentolamine > prazosin. Functional assays performed on myometrium showed that noradrenaline, phenylephrine and clonidine elicited concentration-dependent contractions only in dioestrus and pro-oestrus preparations and that clonidine was more effective than phenylephrine as a contractile agent. It appeared that there were no significant modifications in -AR affinity or concentration during the different stages of bovine oestrous cycle, whereas the uterine spontaneous activity and the responsiveness to -adrenergic stimulation was strongly influenced by hormonal levels. The modifications of uterine contractility observed during the oestrous cycle may be related to modifications induced in the transductional mechanisms of -ARs.     

Intestinal atresia and stenosis: A review comparing its morphology

A review of the literature on intestinal atresia of domestic animal species and humans was done. The 5 types of intestinal occlusions described in human infants are atresia type 1, atresia type 2, atresia type 3, stenosis, and the apple peel or Christmas tree deformity. The intestinal defects described in domestic animal species such as the bovine, equine and porcine are similar to those of human infants. The T-formation, an intestinal defect of the bovine resembling atresia type 3, and rectal stricture, an acquired intestinal defect of the porcine resembling stenosis, were described recently. Intestinal atresia is similar in several species and these similarities raise the questions as to whether the pathogenic mechanism and possibly etiologies of intestinal atresia are similar in these species.     

Antibody Responses in Sheep Vaccinated against Staphylococcus aureus Mastitis: A Comparison of Two Experimental Vaccines Containing Different Adjuvants

A double-blind, placebo-controlled study was conducted to compare two vaccines using different adjuvants with regard to their ability to stimulate antibody production against the - and -toxins and the exopolysaccharide of Staphylococcus aureus. The vaccines contained identical antigens, consisting of inactivated whole bacteria of two strains of S. aureus in addition to - and -toxoid. One vaccine contained mineral oil, while the other used a water-soluble acrylic acid polymer resin (Carbopol) as adjuvant. Saline served as the placebo. One hundred and forty ewes were vaccinated twice before lambing, by subcutaneous injection with vaccine or placebo in the region of the supramammary lymph node, and were observed and sampled over a period of 6 months. The vaccine containing mineral oil as adjuvant induced significantly greater immune responses to the - and -toxins than did the vaccine containing Carbopol. The latter vaccine induced higher levels of antibodies to exopolysaccharide. The degree of local adverse reactions did not differ between the two groups. The results indicate differences between the oil-adjuvanted and Carbopol-adjuvanted vaccines with regard to their ability to stimulate antibody production against S. aureus protein antigens in sheep.     

Feed intake and rumen motility in dwarf goats. Effects of some α-adrenergic agonists,prostaglandins and posterior pituitary hormones

The purpose of the present investigation was to test the hypothesis that drug-induced changes in rumen contractions influence feed intake in dwarf goats. Intravenous (i.v.) administration of clonidine (1 g kg^-1 min^-1 for 10 min), xylazine (1 g kg^-1 min^-1 for 10 min), and PGF-2 (10 g kg^-1 min^-1 for 15 min) caused bradycardia and inhibition of rumen contractions. However, no appetite-stimulating effect of these drugs was observed. Other clinical changes induced by the ₂-adrenergic agonists included slight sedation and a decrease in body temperature; all clinical effects of clonidine and xylazine were partly antagonized by tolazoline pretreatment (10 g kg^-1 min^-1 for 30 min). These results suggest that the CNS control of feeding differs in ruminants and monogastric species.In dwarf goats fasted for 2 h, i.v. administration of oxytocin (0.01 IU kg^-1 min^-1 for 15 min), vasopressin (0.01 IU kg^-1 min^-1 for 15 min), octapressin (0.003 IU kg^-1 min^-1 for 15 min) or PGE (0.8 g kg^-1 min^-1 for 15 min) did not change feeding behaviour during the two observation periods (0–30 min and 180–210 min after drug infusion, respectively). In previous studies, similar doses of these drugs induced changes in heart rate and inhibition of rumen contraction in goats. These findings demonstrate that drug-induced changes in forestomach contractions do not simply cause changes in feeding behaviour. The i.v. infusion of the PGF₂ analogues etiproston (10 g kg^-1 min^-1 for 15 min), luprostiol (30 g kg^-1 min^-1 for 15 min), cloprostenol (1 g kg^-1 min^-1 for 15 min) and tiaprost (1 g kg^-1 min^-1 for 15 min) induced hypophagic effects and stimulated intestinal propulsion.     

Haemophilus influenzae and the β-adrenergic system: A review

Haemophilus influenzae is a bacterium that often can be isolated from the deeper respiratory airways of patients with chronic asthmatic bronchitis. In the present study the effects ofH. influenzae vaccination on guinea pig pulmonary -adrenoceptor number and function (in vitro and in vivo) have been evaluated. Functioning of -adrenoceptors is determined by measuring the -mimetic effect of isoprenaline on the inhibition of anaphylactic mediator release and isolated tracheal strip relaxation. The number of -adrenoceptor binding sites was measured by means of a³H-dihydroalprenolol binding assay.Also the mechanism of action underlying the changes in -adrenoceptor functioning was evaluated. Furthermore, it was established that the effect on the -adrenoceptor system was not specific forH. influenzae and that other respiratory pathogens were also biologically active in this respect.     

Endotoxin in the conscious piglet: Its effects on some general and gastrointestinal myoelectrical parameters

The effect of an intravenous bolus injection of endotoxin, 0.1, 1 or 10 g/kg, on rectal temperature, clinical appearance, haematological parameters, and on gastrointestinal electrical activity was examined in 11 conscious piglets of 4–5 weeks of age, with implanted electrodes in the antrum pylori, duodenum, jejunum and ileum. All doses resulted in a significant and dose-dependent increase in rectal temperature, in pronounced clinical signs and in distinct changes in haematological values. These included shivering, depression, respiratory distress, a leukopenia (0.1 g/kg) or a leukocytosis (1 g/kg) with a shift to the left, an accelerated sedimentation rate and a decreased packed cell volume. Doses of 1 and 10 g/kg induced a transient inhibition of gastroduodenal electrical activity. These results suggest that, in the piglet, endotoxin primarily manifests general clinical signs and that the gastrointestinal effects coincide with these.     

The phenomenon of stress: Concepts and mechanisms associated with stress-induced responses of the neuroendocrine system

Stress, stressors and the stress response are terms which represent concepts rather than oeing precisely definable. No single theory of stress has been universally accepted. Selye's General Adaptation Syndrome of stress remains the primary theory for the basis of stress research in food-producing animals; however, other concepts and theories have been developed. This paper reviews current theories and suggests that the complexity of research on stress in food-producing animals can be attributed to the lack of concrete theories and concepts regarding identifiable stressors, the endocrine responses stimulated by potential stressors and the complex and integrated biological changes in the neuro-endocrine system resulting from exposure to hypothesized stressors.     

Uterine motility of the sow during the oestrous cycle and early pregnancy

With electromyography and strain gauges the uterine motility of the sow during the oestrous cycle and early pregnancy was studied. Special attention was paid to characterization of myometrial activity at the time of intrauterine migration of blastocysts.From recordings of 4 animals (3 became pregnant) 3 types of electrical spiking activity (each could be correlated with an elevation of the strain gauge tension) were discerned. Two of them appeared regularly and were suitable for analysis: High Voltage Slow Acticity (with relative high amplitude and low frequency of spikes) and Low Voltage Fast Activity (with relative low aplitude and high frequency of spikes).The sexual status markedly influenced myometrial activity: during prooestrus and oestrus only one type of electrical activity was present whereas the myoelectrical complex (an episode of this activity and the subsequent interval of inactivity) was shorter than 10 min. During dioestrus the myoelectrical complex was longer than 10 min and High Voltage Slow Activity (solely on the cervix and bifurcation) and Low Voltage Fast Activity occurred simultaneously in episodes which mainly appeared to originate on the bifurcation.The characteristics of uterine activity during pregnancy were similar to those of a cyclic sow until day 12. It was only on day 12 that gestation appeared from an increased frequency of myoelectrical complexes.It is concluded that Low Voltage Fast Activity as it was found on the uterine horn at days 8–9 might be involved in the process of intra-uterine migration of blastocysts. In cyclic and in pregnant animals the patterns of Low Voltage Fast Activity were similar. Therefore, the occurrence of Low Voltage Fast Activity is independent of the actual presence of blastocysts. It seems to be exhibited in dependence on the ovarian hormones.     

Milk Protein Polymorphism in Kangayam Cattle

This paper reports the milk protein polymorphism, the allele frequencies of variants and the possible linkages among various combinations of milk protein phenotypes in the Kangayam cattle of south India. Milk samples from 156 Kangayam cows were typed by starch gel and polyacrylamide gel electrophoresis for caseins and whey proteins, respectively. All the four milk protein components studied, _s1-casein, -casein, -lactoglobulin and -lactalbumin, exhibited polymorphism with high allele frequencies of 0.9231±0.0151 for _s1-casein C, 0.9263±0.0148 for -casein A, 0.9135±0.0159 for -lactoglobulin B and a relatively high frequency of 0.6218±0.0275 for -lactalbumin A. The mean heterozygosity estimated over all the four milk protein loci was 0.2420. Genetic equilibrium was observed among all the loci studied, except -lactalbumin. Linkage analysis confirmed the non-independence between _s1- and -caseins and between caseins and -lactalbumin phenotypes.     

The pharmacokinetics of fenbendazole and oxfendazole in cattle

The pharmacokinetics of fenbendazole and oxfendazole in cattle are described. The pharmacokinetics of oxfendazole were not significantly different when administered orally and by intra-ruminal injection. At a dose rate of 4.5 mg/kg, administered orally, fenbendazole gave rise to mean peak concentrations in plasma of fenbendazole and oxfendazole of 0.11 and 0.13 g/ml respectively. Oral administration of oxfendazole, at 4.5 mg/kg body weight, gave rise to plasma peak concentrations of fenbendazole and oxfendazole of 0.10 and 0.20 g/ml respectively. Following intra-ruminal administration of oxfendazole, the peak concentrations were 0.11 and 0.18 g/ml respectively.     

Kinetics of Interferon-Gamma Production and its Comparison with Anti-Listeriolysin O Detection in Experimental Bovine Listeriosis

The kinetics of the production of interferon gamma (IFN-) in whole blood culture and its comparison with anti-listeriolysin O (ALLO) detection by ELISA were studied during oral infection of calves with Listeria monocytogenes. Culture filtrate antigen (CFA), listeriolysin O (LLO), and sonicated antigen (SA) were used to prime the peripheral blood mononuclear cells (PBMCs) and the plasma from orally infected calves. IFN- and ALLO appeared as early as day 7 of an oral infection. IFN- was detected earlier with LLO than with SA. The Max50 interleukin (IL-2) activity and IFN- estimated in the culture supernatant from PBMCs primed in vitro with different antigens of L. monocytogenes revealed high induction of IL-2 and IFN- by CFA, LLO and live antigen. IFN- assay and ALLO detection were used for testing cases of repeat breeding in dairy cattle. It appeared that detection of IFN- employing LLO can be used to diagnose listerial infections.     

A study of the interaction between bromocresol green dye and bovine,ovine and equine serum globulins

In human medicine it has been shown that the bromocresol green (BCG) dye-binding method for the determination of serum albumin is not entirely specific, the dye reacting also with certain human serum globulins. This causes over-estimation of albumin when reaction times are prolonged beyond 30 seconds.In the present study, serum albumin values obtained from three animal species by the immediate, i.e. less than 30 seconds, BCG reaction were compared with those by the 10-minute BCG reaction. Albumin-depleted sera were prepared using an affinity chromatography technique and their reactions and those of purified gamma globulin preparations with the dye were studied.In cattle, sheep and horses, serum albumin values obtained by the 10-minute reaction were higher than those obtained by the immediate BCG reaction, the differences being statistically significant. Purified gamma globulin did not react with the BCG dye after 10 minutes, but other globulins did. There were differences between the species in the magnitude of the reaction of their globulins with BCG dye.     

The use of divalent cation chelating agents (EDTA/EGTA) to reduce non-specific serum protein interaction in enzyme immunoassay

An indirect enzyme immunoassay (ELISA) for detection of bovine antibody toBrucella abortus was modified by the addition of divalent chelating agents to the serum diluent. This addition resulted in an increase in specificity from 96.0% in the regular assay to 99.4% in the modified procedure. Of the 15 715 sera initially tested by the indirect ELISA, 691 that had given positive reactions were selected for retesting in the indirect ELISA with EDTA/EGTA added. The buffered plate antigen test (BPAT) correctly identified 98.6% of the samples as negative. The addition of chelating agents did not alter the sensitivity of the indirect ELISA, which correctly classified 609 sera from animals from whichB. abortus had been isolated as positive. The sensitivity of the BPAT was 97.8%.Abbreviations ABTS 2,2-azinobis(3-ethylbenzthiazoline sulphonic acid) - BPAT buffered plate antigen test - EDTA ethylenediaminetetraacetic acid disodium salt - EGTA ethylene glycol-bis(-aminoethyl ether)-N,N,N,N-tetraacetic acid - ELISA enzyme-linked immunosorbent assay - IgG₁ immuno- globulin G₁ - IgM immunoglobulin M - Tris tris(hydroxymethyl)aminomethane     

Muscle growth in sheep

Growth rates of muscle relative to empty body weight were computed for the Peppin Merino, a breed of sheep considered unimproved for meat production. Rates of muscle increase in the Merino sheep were comparable to growth coefficients reported for the Romney and Southdown breeds which were tabulated separately by sex. Pooled data for the Lincoln, Hampshire, Southdown, Suffolk and Welsh breeds were analyzed relative to empty body weight.No significant difference in muscle growth rates were found in direct comparisons based on starved body weights for the Romney and Southdown breeds (Fourie et al., 1970). From the standpoint of conformation these breeds might be expected to differ in muscle growth rate as the Romney is considered a leggy sheep and the Southdown a blocky animal. Growth coefficients for muscle in the Romney, Southdown and several other breeds were very similar to the Peppin Merino.     

Leukocyte and Cytokine Accumulation in the Ovine Teat and Udder during Endotoxin-Induced Inflammation

Persson Waller, K., Colditz, I.G., Flapper, P. and Seow, H.-F., 1997. Leukocyte and cytokine accumulation in the ovine teat and udder during endotoxin-induced inflammation. Veterinary Research Communications, 21 (2), 101-115The accumulation of leukocytes, ovine serum albumin and the cytokines interleukin-1 (IL-1), tumour necrosis factor- (TNF-), interleukin-8 (IL-8), granulocyte-macrophage colony-stimulating factor (GM-CSF) and interferon- (IFN-) was studied during endotoxin-induced inflammation in lactating and dry ovine udders, and in the teat cisterns of dry ewes after surgical closure of the passage between the teat and udder cisterns. Samples were taken before infusion and hourly up to 10 h after infusion of 0.1, 1 or 10 µg of endotoxin, or infusion of pyrogen-free saline (PFS) as a control. Rectal temperatures were measured.A significant dose- and time-dependent accumulation of leukocytes, mainly neutrophils, was observed in the lactating udders and in the teat cisterns. In the dry udders, the leukocyte accumulation was significant for time but not for dose. Peak numbers of cells were reached at 3-4 h in the dry udders and in the teat cisterns, but not until 10 h after infusion in the lactating udders. The changes in the ovine serum albumin concentrations mostly paralleled changes in leukocyte numbers.A role was indicated for TNF-, IL-8 and GM-CSF, but not for IL-1 and IFN-, during endotoxin-induced inflammation in the ovine udder. Release of TNF-, IL-8 and GM-CSF was most prominent in lactating udders, peaking at 2 or 3 h after infusion, but was also detected in dry udders and teat cisterns. Detectable levels of IL-1 and IFN- were occasionally found in all three groups.