Sulfur-induced polioencephalomalacia in sheep: some biochemical changes.

The effect of high dietary sulfur (S) supplementation on blood thiamine (B1) concentration, biochemical indices of liver, muscle and kidney damage and selected plasma electrolytes was studied in six sheep. Three of these sheep received an additional 230 mg thiamine/kg diet (Group 2). After approximately 2.5-3 weeks on this diet, all three sheep in the non-B1-supplemented group (Group 1) showed loss of appetite and developed mild neurological signs: depression, intermittent signs of excitation and head pressing. Increases in blood B1 concentration and plasma creatine kinase (CK) and aspartate aminotransferase (AST) were observed during this time in all affected animals. Clinical signs lasted only for two to five days. Sheep in group 2 were clinically normal throughout the experiment, but all of these animals also had elevated blood B1 concentrations and plasma CK activity at the 3 wk sampling. Plasma magnesium concentrations of group 1 sheep were elevated at the 2.5-3 wk and 6 wk samplings but they declined significantly (p less than 0.05) to low normal levels thereafter. Magnesium concentrations of group 2 sheep were low at the beginning but progressively increased during the course of the experiment. At necropsy, brain lesions suggestive of polioencephalomalacia (PEM) were observed in all sheep but were most marked in group 1. It is speculated that PEM may be caused by a direct toxic effect of S, S metabolites or B1 antimetabolites in the brain rather than by an in vivo B1 deficiency per se.     

Diagnostic value of serum gamma-glutamyl transferase and alkaline phosphatase activities in hepatobiliary disease in the cat

The diagnostic value of serum gamma-glutamyl transferase (GGT) activity and serum alkaline phosphatase (ALP) activity in the detection of liver disease in the cat (n = 69) was compared. On the basis of histologic examination of the liver, cats were assigned to 8 groups: group 1--complete extrahepatic bile duct obstruction (n = 5), group 2--cholangiohepatitis-cholangitis syndrome (n = 11), group 3--hepatic lipidosis (n = 15), group 4--neoplasia, including lymphosarcoma and myeloproliferative disease (n = 9), group 5--hepatic necrosis (n = 7), group 6--cirrhosis (n = 3), group 7--portosystemic vascular anomaly (n = 4), and group 8--miscellaneous (n = 15). Cats assigned to group 8 lacked substantial histologic abnormalities of the liver. The mean value +/- SD of GGT in 20 clinically normal cats was 0.44 +/- 0.26 IU/L. The highest GGT activity in clinical patients developed in groups 1, 2, and 6. The highest ALP activity developed in groups 1 to 4. Significant correlations between GGT and ALP activities were detected only in groups 2 (P less than 0.001) and 5 (P less than 0.10). Among 54 cats with hepatic disease, only 11% had both the GGT and ALP activities within the normal ranges. Comparatively, 52% had ALP activities within the normal range, and 17% had GGT activities within the normal range.(ABSTRACT TRUNCATED AT 250 WORDS)     

Alternate grazing of horses and sheep as control for gastro-intestinal helminthiasis in horses

Gastro-intestinal helminth of a group of three yearling mare Shetland ponies, which were set-stocked on a small pasture from February until September, were compared with those of a similar group of ponies, which grazed a similar pasture from February to July and subsequently was removed to a pasture which had been grazed by sheep from April to July. In addition both groups were treated with cambendazole when the latter group was removed to the sheep pasture.Pasture larval counts and worm counts demonstrated that the group grazed after the sheep acquired considerably smaller burdens of nematodes of the subfamilies Cyathostominae and Strongylinae, but considerably higher burdens of Trichostrongylus axei than the group which remained on the same pasture. The T. axei infections in the former group caused an increase in the serum pepsinogen levels within two weeks after removal to the sheep pasture followed by a gradual decrease. At necrospy T. axei populations consisted almost exclusively of inhibited early third state larvae.     

Colostral transfer of gamma glutamyl transferase in lambs

Serum gamma glutamyl transferase (GGT) levels in blood samples taken from normal lambs which had suckled colostrum were found to be up to 140 times normal adult levels. These high serum levels declined rapidly reaching a stable level approximately 60% higher than normal adult values by 24 days of age. Newborn lambs which had not yet consumed colostrum had GGT levels which would be considered normal in adult sheep. The GGT concentration in ewes' colostrum was up to 470 times normal serum levels. There was a significant positive correlation between serum GGT and gamma globulin levels in blood samples taken from lambs within 24 hours of birth.

Lambs' serum alkaline phosphatase (AP) and serum glutamate oxaloacetate transaminase (SGOT) levels also rose concurrently with the absorption of colostral gamma globulin, with the day 1 AP values being significantly correlated with the serum gamma globulin levels. Serum AP levels declined gradually but were still well above normal adult levels at 45 days of age while SGOT levels returned to normal adult levels by two to three days after birth.

It is concluded therefore that, as previously shown in calves, lambs acquire high levels of serum GGT activity from their mothers' colostrum in proportion to the amount of gamma globulin absorbed and also show a concurrent rise in serum AP activity. However the rise in SGOT levels at this time has not been observed in calves.     

A comparison of serum biochemical changes in two breeds of sheep (Red Masai and Dorper) experimentally infected with Fasciola gigantica.

Twelve Red Masai and 12 Dorper sheep aged between 6 and 9 months, were acquired from a fluke-free area and sheep of each breed divided into two equal groups of six. Each animal in one group of each breed was experimentally infected with 400 viable metacercariae of Fasciola gigantica. The other groups acted as uninfected controls. Blood samples were taken at weekly intervals for the determination of serum bilirubin, albumin, and gamma glutamyl transferase levels. Following the establishment of infection, albumin levels declined in both breeds of infected animals without any significant difference between the two breeds. However, serum bilirubin and gamma glutamyl transferase (GGT) in the infected animals were elevated significantly more in the Dorper than in the Red Masai sheep. Based on these findings, it would appear that Dorper sheep are more susceptible to the infection than Red Masai sheep.     

WHITE LIVER DISEASE OF SHEEP

SUMMARY Outbreaks of ovine white liver disease (WLD) on 7 farms in eastern Victoria were investigated. Most occurred in late spring and mainly affected lambs 3 to 6 months old, with a morbidity of 20 to 100% and mortality of 8 to 15%. Clinically affected lambs showed illthrift, emaciation and bilateral, serous, ocular discharge. Clinical pathology showed mild anaemia, elevated serum liver enzymes (GGT, OCT, AST) and low levels of serum vitamin B12. Grossly, the livers were pale, fatty and friable; microscopically there was parenchymal fatty change, bile duct proliferation and ceroid pigmentation. Liver cobalt values were consistently low (mean 0.4 ± 0.4 μmol/kg D.W.). Levels of cobalt in pasture from 2 properties were very low (0.34 μmol/kg D.W.). The diagnosis of white liver disease was made on the basis of clinical features, specific liver pathology and low cobalt status. Treatment trials established that cobalt injections or oral bullet administration resulted in clinical improvement, significant weight gains, and improved serum vitamin B12 levels. WLD did not recur in previously affected sheep using these treatments. However, when blocks containing cobalt were available continuously, WLD recurred 2 years after the initial outbreak.     

Diagnostic efficacy of serum alkaline phosphatase and gamma-glutamyltransferase in dogs with histologically confirmed hepatobiliary disease: 270 cases (1980-1990).

The diagnostic efficacy of serum alkaline phosphatase (ALP) and gamma-glutamyltransferase (GGT) activities was examined, using the records of 270 dogs initially suspected of having hepatobiliary disease on the basis of history, findings on physical examination, results of baseline screening tests, or any combination of these data. Histologic examination of hepatic tissue was performed in each dog. Sixty-three dogs did not have histologic evidence of hepatobiliary disease and served as the control group. On the basis of diagnosis, dogs were assigned to 1 of 8 groups: dogs with cirrhosis (n = 34), steroid hepatopathy (n = 16), hepatic neoplasia (primary and secondary, n = 36), chronic hepatitis (n = 14), chronic passive congestion (n = 5), hepatic necrosis (n = 17), portosystemic vascular anomaly (n = 35), and cholestasis (extrahepatic bile-duct obstruction and intrahepatic cholestasis, n = 50). Of the 207 dogs with hepatobiliary disease, 29 (14%) had normal ALP and GGT activities, 31 (15%) had normal ALP activity, and 112 (54%) had normal GGT activity. Of the 63 control dogs, 29 (46%) had normal serum ALP and GGT activities, 32 had normal ALP activity (ALP specificity, 51%), and 55 had normal GGT activity (GGT specificity, 87%). The specificity of ALP and GGT in parallel (positive result = result of either test abnormal) was 46%, and in series (positive result = results of both tests abnormal) was 91%. The highest median activities of ALP developed in dogs with cholestasis, steroid hepatopathy, chronic hepatitis, and hepatic necrosis. The highest median activities of GGT developed in dogs with steroid hepatopathy, cholestasis, and hepatic necrosis.(ABSTRACT TRUNCATED AT 250 WORDS)     

放牧强度对高寒草地产草量及羊体质量增加的影响

以托云牧场高寒草地为研究对象,通过设置3个放牧样地,一个对照样地,研究不同强度放牧对草地地上生物量的影响以及在不同放牧压力下羊体质量增加的效果。结果表明,1）托云牧场是以银穗草（Leucopoa albida）、羊茅（Festuca arioides）、点地梅（Androsace umbellata）和棘豆（Oxytropis falcatae）为优势种的高山草地;2）高寒草地地上生物量较低,禁牧区7月地上生物量（干物质）仅830 kg·hm-2;3）放牧活动对地上生物量有较大影响,重度放牧能显著降低牧场地上生物量;4）以羊体质量增加值为评价指标,该高寒牧场在载畜量为1.05羊单位·hm-2时能获得较好的体质量增加效果。     

Colostral transfer of gamma glutamyl transferase in lambs

Serum gamma glutamyl transferase (GGT) levels in blood samples taken from normal lambs which had suckled colostrum were found to be up to 140 times normal adult levels. These high serum levels declined rapidly reaching a stable level approximately 60% higher than normal adult values by 24 days of age. Newborn lambs which had not yet consumed colostrum had GGT levels which would be considered normal in adult sheep. The GGT concentration in ewes' colostrum was up to 470 times normal serum levels. There was a significant positive correlation between serum GGT and gamma globulin levels in blood samples taken from lambs within 24 hours of birth. Lambs' serum alkaline phosphatase (AP) and serum glutamate oxaloacetate transaminase (SGOT) levels also rose concurrently with the absorption of colostral gamma globulin, with the day 1 AP values being significantly correlated with the serum gamma globulin levels. Serum AP levels declined gradually but were still well above normal adult levels at 45 days of age while SGOT levels returned to normal adult levels by two to three days after birth. It is concluded therefore that, as previously shown in calves, lambs acquire high levels of serum GGT activity from their mothers' colostrum in proportion to the amount of gamma globulin absorbed and also show a concurrent rise in serum AP activity. However the rise in SGOT levels at this time has not been observed in calves.     

喀斯特山区草地施肥对放牧乌蒙半细毛羊抗氧化系统功能的影响

为选择草地施肥的肥料种类,减少施肥对乌蒙半细毛羊产业的影响,在威宁县凉水沟种羊场多年生人工草地开展施肥和放牧试验。 结果表明:凉水沟种羊场人工草地牧草铜含量相对较低,但仍高于乌蒙半细毛羊营养需要标准;施肥极显著增加牧草氮含量(P<0.01),各施肥处理之间没有明显差异。硫酸铵施肥显著增加牧草硫和锌含量(P<0.01),显著降低了牧草硒的含量(P<0.01)。放牧试验结束时,施硫酸铵草地的乌蒙半细毛羊血液中铜、铁和硒的含量极显著低于施硝酸铵草地和对照组(P<0.01), 动物血液锌和硫含量极显著高于硝酸铵施肥牧场和对照组(P<0.01)。硫酸铵施肥牧场的乌蒙半细毛羊血红蛋白、红细胞压积容量极显著低于硝酸铵施肥牧场和对照牧场(P<0.01),血清铜蓝蛋白含量、血清超氧化物歧化酶活力、血清谷胱甘肽过氧化物酶活力和血清过氧化氢酶等抗氧化酶的活力极显著低于硝酸铵施肥牧场和对照牧场(P<0.01),丙二醛的含量显著高于硝酸铵施肥牧场和对照牧场(P<0.01)。血液其他矿质元素和血液指标及血清生化值在2个施肥处理和对照之间均差异不显著。 因此得出结论,草地施肥的种类需要根据土壤矿物质分布和含量情况确定,铜含量低的牧场不适合硫酸铵施肥,硫酸铵施肥明显影响了乌蒙半细毛羊机体抗氧化系统功能。     

Distribution of 5'-nucleotidase in the tissues of sheep and the effect of kidney and liver lesions on the activity of the enzyme in plasma and urine

The distribution of 5'-nucleotidase (5'-NT) activity in the tissues of the sheep differs from that of gamma glutamyl transferase (GGT). Nevertheless, both enzymes are released into the plasma of sheep which have been infected with Fasciola hepatica or in which the bile duct has been ligated. In a sheep dosed with sporidesmin, a fungal toxin which damages the biliary tract, there was an increase in GGT activity in the plasma and urine but no change in 5'-NT activity. Neither enzyme was released into the plasma or urine of sheep dosed with carbon tetrachloride. In sheep with renal tubular necrosis and hepatocellular necrosis caused by dosage with hexachlorobutadiene, both enzymes were released into the plasma, and GGT, but not 5'-NT activity was found in urine. In sheep with tubular necrosis of the kidney caused by the administration of mercuric chloride, GGT activity, but not 5'-NT, increased in the plasma and urine.     

The occurrence of Anthrax in New Zealand

A field outbreak of facial eczema occurred during a vitamin B12 response trial in young growing sheep. Pasture cobalt levels were in the low range for sheep <0.08 mg/kg, 1.358 µmol/kg) and mean (of 3) liver vitamin B12 levels in the sheep were low (>100 nmol/kg) during the period in which facial eczema occurred.

Mean serum vitamin B12 levels of the untreated group were low (>185 pmol/1) for the two months (January and February) preceding the period of facial eczema. However, levels showed an approximate 3.5 fold increase in both cobalt supplemented and unsupplemented groups with the onset of facial eczema in March. From February to March the mean serum vitamin B12 and glutamyl transferase (GGT) activity showed parallel increases with a positive correlation (r = 0.73) between log serum vitamin B12 and log serum GGT activity during the period January to July for both groups. This finding suggested that the increase in serum vitamin B12 was due to sporidesmin induced liver damage.

The diagnostic implication is that, in areas where facial eczema is a problem, liver is the sample of choice for determining vitamin B12 status, because sporidesmin toxicity can elevate low serum vitamin B12 levels to diagnostically normal levels.     

The effect of sporidesmin toxicity on ovine serum vitamin B12 levels

A field outbreak of facial eczema occurred during a vitamin B12 response trial in young growing sheep. Pasture cobalt levels were in the low range for sheep (<0.08 mg/kg, 1.358 micromol/kg) and mean (of 3) liver vitamin B12 levels in the sheep were low (<400 nmol/kg) during the period in which facial eczema occurred. Mean serum vitamin B12 levels of the untreated group were low (<485 pmol/l) for the two months (January and February) preceding the period of facial eczema. However, levels showed an approximate 3.5 fold increase in both cobalt supplemented and unsupplemented groups with the onset of facial eczema in March. From February to March the mean serum vitamin B12 and glutamyl transferase (GGT) activity showed parallel increases with a positive correlation (r = 0.73) between log serum vitamin B12 and log serum GGT activity during the period January to July for both groups. This finding suggested that the increase in serum vitamin B12 was due to sporidesmin induced liver damage. The diagnostic implication is that, in areas where facial eczema is a problem, liver is the sample of choice for determining vitamin B12 status. because sporidesmin toxicity can elevate low serum vitamin B12 levels to diagnostically normal levels.     

Comparison of a novel form of zinc with zinc oxide bolus licensed for prevention of facial eczema,and interaction with copper oxide in sheep

To evaluate a novel elemental zinc bolus compared with a registered positive control zinc oxide bolus and assess serum zinc concentrations following concomitant treatment with a capsule containing copper oxide needles. Forty Romney-cross ewes were randomly allocated in a 2 × 2 factorial design study. On Day 0, 20 ewes received novel boluses containing elemental zinc (Investigational Veterinary Product, IVP) while 20 received a zinc oxide bolus (control; CP). Half the animals in each zinc treatment group (n = 10) were treated with a copper oxide needle capsule [Copasure® - Ewe]. Weekly, from Day −7 to 56, all ewes were assessed for signs of photosensitization, and for 10 ewes from each zinc treatment groups, samples were collected for analysis of serum GGT activity, serum zinc concentrations, faecal zinc concentrations and on Days −7 and 56, liver copper concentrations. Multivariable random-effects models assessed the effects of zinc treatment, copper treatment, treatment interactions and time on all analytes. Regression models examined associations between serum and faecal zinc concentrations and GGT activity. Low spore numbers indicated low Pithomyces chartarum challenge. Serum zinc levels were significantly higher in the IVP than in the CP group [p < 0.0001] and varied by time [p < 0.001] and positively associated with faecal zinc concentration [p < 0.001]. Copper treatment did not affect serum zinc [p = 0.82] or faecal zinc [p = 0.92] concentrations. Liver copper concentrations did not differ between zinc treatment groups on Day −7 [p = 0.6] or Day 56 [p = 0.95]. Only the CP/no copper group had no increase in liver copper concentrations.     

Effect of different times of administration of the nematophagous fungus Duddingtonia flagrans on the transmission of ovine parasitic nematodes on pasture--a plot study

Investigations were made into the timing of administration of Duddingtonia flagrans as a biological control agent against ovine parasitic nematodes including stongylid and Nematodirus spp. Faeces from 3-4 months old male lambs were deposited onto pasture plots that had never been grazed by sheep. The trial was conducted over two consecutive years (1998 and 1999). For both years, the following three plot types were involved: Sim plots had faeces containing nematode eggs and Duddingtonia flagrans spores deposited simultaneously; Post plots had faeces containing nematode eggs followed 2 weeks later by faeces containing D. flagrans spores alone; Control plots had faeces containing only nematode eggs; Prior plots (included in 1999) had faeces containing D. flagrans spores alone followed 2 weeks later by faeces containing nematode eggs. In each year, two deposition periods were involved: July and August in 1998 and June and July in 1999. During the first year pasture samples were collected at 2, 4, 6, 8 and 12 weeks after initial deposition. In 1999, additional samples were collected at 10, 16 and 20 weeks. Larvae were extracted from the pasture samples and counts performed to estimate the number and species of infective third-stage (L(3), larvae) present. The number of third-stage strongylid larvae on pasture was significantly lower on Sim plots compared to the remaining plot types for both years at all deposition times (P<0.001). This was also the case for the number of Nematodirus infective larvae in August deposition plots in 1998 (P<0. 02). There was no significant difference between treatments in both deposition times in 1999 and July deposition plots in 1998 for the Nematodirus data. These results suggest that D. flagrans, if deposited at the same time as parasite eggs prevents transmission of third-stage larvae from the faecal deposit onto pasture, including occasionally Nematodirus species, but does not have an effect on third-stage parasitic nematode larvae in the surrounding soil.     

Bovine Dictyocaulosis: Pattern of Infection and the Prevention of Parasitic Bronchitis

A combined epidemiology and control investigation was performed with parasite-free calves turned out in May on a permanent pasture naturally contaminated with lungworm larvae the previous year. Before the start the field was divided into two plots. One plot was grazed by 12 calves after the first week of May. The other plot was grazed by 12 calves turned out two weeks later. Both groups as well as the plots grazed by them were subdivided six weeks after turning out. Based on a predicted rise in the pasture larval contamination with infective lungworm larvae, one subgroup of each main group was given a tactical anthelmintic treatment six weeks and again eight weeks after their date of turning out. Patent infections from overwintered larvae were detected in both main groups after four weeks of grazing, but not in all individuals of the late turned-out group. The excreted larvae gave rise to pathogenic pasture larval contaminations on the two initial plots five to six weeks after turning out. In the control groups, early turning-out resulted in approx. 10 times higher larval recoveries in faeces and pasture compared to late turning-out. Seven to eight weeks after turning-out critical, severe parasitic bronchitis had developed in the early turned-out control group. In the late turned-out controls, clinical signs were obvious but not critical. Outbreaks were not observed in any of the experimental subgroups, and no larval excretion was observed among them within four to five weeks following treatments. Similarly, no larvae were recovered from their pastures two weeks after treatment and onwards. A third treatment was given to both experimental groups on the same date (August 21) to suppress gastrointestinal parasitism. However, the level of this infection, appeared moderate, probably due to comparatively low precipitation and extensive supplementary feeding given in late summer to compensate for scarcity of grass.     

Transmission of virulent footrot between sheep and goats

OBJECTIVE: To determine the infectivity of ovine and caprine strains of Dichelobacter nodosus for both sheep and goats. DESIGN: Pen experiments in which 20 sheep and 19 goats were challenged directly with the two strains, and transmission experiments on pasture, using donors infected by experimental challenge. RESULTS: Sheep and goat strains of D nodosus infected both animal species in experimental challenges. Animals so infected transmitted footrot to both sheep and goats on pasture plots. A significantly smaller proportion of goats than sheep was infected when challenged with either strain. The interval between exposure and development of footrot in goats was longer than in sheep when recipient animals were exposed to infected donors on pasture. The disease was less invasive in goats than in sheep. CONCLUSIONS: With the strains of D nodosus used there was no evidence of host specificity. Direct transmission of footrot can occur between sheep and goats in the same environment. There is a need to include goats in ovine footrot eradication programs and vice versa.     

A preliminary study of serum haptoglobin concentration as a prognostic indicator of ovine dystocia cases.

Serum samples were collected prior to the correction of dystocia in 45 sheep and from nine sheep following a normal parturition. Serum samples collected from a group of 16 non-pregnant ewes acted as non-pregnant controls. The mean serum haptoglobin concentration was significantly elevated (P less than 0.01) in those dystocia cases where dead lambs were present in utero compared to those ewes which had live lambs delivered. While the number of cases presented in this study is small, there is an indication that sheep with a serum haptoglobin concentration above 1.0 g/l represent a poor surgical risk. The three ewes which died following a caesarean operation had markedly elevated serum haptoglobin concentrations prior to surgery indicating an inflammatory reaction. Five ewes with a haptoglobin concentration of 0.4 g/l made an uneventful recovery following a caesarean operation.     

Photosensitivity in South Africa. VI. The experimental induction of geeldikkop in sheep with crude steroidal saponins from Tribulus terrestris

Geeldikkop was induced in sheep by the oral administration of crude steroidal saponins from Tribulus terrestris. Two of the sheep developed typical lesions of geeldikkop, including birefringent crystalloid material in bile ducts and concentric periductal lamellar fibrosis. The clinical pathological changes in these sheep were also consistent with those of geeldikkop: aspartate transaminase and gamma-glutamyl transferase activities in the sera of both were elevated, and one had bilirubinaemia. A third sheep became photosensitive without typical lesions of geeldikkop in the liver or changes in the activities of liver enzymes before euthanasia. The findings of these trials are consistent with reports from abroad that ovine hepatogenous photosensitization, caused by Agave lechuguilla and Narthecium ossifragum, can be induced with crude saponins from the respective plants.     

Effects of heparin, citrate, and EDTA on plasma biochemistry of sheep: Comparison with serum

The effects of various types of anticoagulants on plasma biochemistry were studied in man and various animals, but limited information is existing for sheep plasma biochemistry. Ten clinically healthy Baloochi breed of sheep were blood sampled in different tubes containing each anticoagulants and plain tube for harvesting plasma and serum. The concentrations of glucose, cholesterol, total bilirubin, urea, creatinine, total protein, albumin, calcium, inorganic phosphorus, and magnesium and the activity of aspartate aminotransferase (AST), alkaline phosphatase (ALP), creatine kinase (CK) and gamma glutamyl transferase (GGT) were measured. Except for the amounts of GGT, bilirubin and inorganic phosphorus, other measured parameters were significantly lower in citrated plasma than that of serum. For corrected citrated plasma significant differences were seen for the concentrations of glucose, creatinine, calcium and the activity of ALP.Most parameters did not show any difference, but significant increase was seen for albumin concentration when heparin was used as an anticoagulant. Using EDTA as anticoagulant caused a significant difference for the concentrations of some of the measured parameters in plasma except glucose, GGT, cholesterol, albumin, bilirubin, CK, and inorganic phosphorus comparing with serum.