Occurrence, isolation and serotyping of Erysipelothrix rhusiopathiae in cattle and pig slurry

In a survey on the occurrence of potential pathogenic bacteria in slurry, Erysipelothrix rhusiopathiae (E. rh.) was found in samples from 49 % of 84 cattle herds, 44 % of 32 pig herds, and 39 % of 67 cattle and pig herds. Among E. rh. isolates from 81 of the herds, 16 different serotypes were distinguished, including 1 serotype not previously described, which was designated serotype 23.Procedures of isolation and serotyping are presented and discussed, and the serotype distribution within the different herd categories is outlined.     

Intracellular distribution of copper and zinc in the liver of copper-exposed cattle from northwest Spain

The intracellular distribution of copper (Cu) and zinc (Zn) in the livers of normal and moderately Cu-exposed cattle was investigated with the aim of improving understanding of the pathophysiology of Cu accumulation in cattle. At total liver Cu concentrations within the generally accepted normal range (25-100 mg/kg fresh weight) the large-granule fraction was the main subcellular compartment for Cu accumulation, followed by the cytosol and the nucleus, whereas in the microsomal fraction Cu accumulation was very low. With increasing Cu exposure, the capacity of the large-granule fraction to accumulate Cu decreased, proceeding towards a plateau (estimated at about 80 mg/kg at a projected total liver Cu concentrations of 450 mg/kg), accompanied by progressively greater Cu accumulation in the nucleus and cytosol. Total liver Cu concentration had little influence on subcellular Zn distribution, with hepatic Cu concentrations being only moderately correlated with Zn concentration in the large-granule fraction. There was a strong association between the proportion of total Cu bound to metallothionein (MT) and the proportion of total Zn in the large-granule fraction, suggesting that Zn displaced from MT is taken up by the lysosomes for excretion. This pattern of Cu accumulation, as in sheep, may be due to the limited capacity for metallothionein binding of Cu and excretion in bile.     

牦牛血液铜锌超氧化物歧化酶cDNA克隆测序

本试验从牦牛血液中提取总RNA,然后用AMV反转录酶对其进行反转录产生第一条cDNA链。根据奶牛Cu/Zn-SODcDNA序列（序列号：NM174615）设计一对PCR引物,对反转录后产生的第一条cDNA链进行PCR扩增,并克隆测序,测序结果为483bp。结果证实可从牦牛血液中提取到少量合成的铜锌超氧化物歧化酶的mRNA。     

The role of metallothionein and zinc in hepatic copper accumulation in cattle

The role of metallothionein (MT) and zinc (Zn) in hepatic copper (Cu) accumulation in calves from a region in North-West Spain has been investigated. In this region there is intensive pig farming, and animals with liver Cu concentrations above normal are not uncommon. Concentrations of hepatic MT were not related to Cu accumulation but were strongly dependent on the Zn status of the animal. When analysing the metal content bound to MT it was observed that Cu-MT values, in the same way as Zn-MT, were directly correlated with MT concentrations in the liver, indicating that although Cu is a poor inducer of MT synthesis, it can compete with Zn for MT binding sites. The ability of Cu to displace Zn from MT is highly dependent on the Cu:Zn ratio in the cell, Cu being the main metal in MT at the higher levels of Cu exposure in Galician cattle. In spite of this, the percentage of the total hepatic Cu bound to MT is very low in these animals, indicating that cattle have a very limited capacity to accumulate Cu-MT in the liver, and may therefore have a greater susceptibility to Cu toxicosis.     

The influence of aging and low zinc nutrition on the choroid in the pig: II. The melanosome

The effects of low zinc nutrition and aging on central choroidal melanosomes were examined in the pig. Melanosomes of central choroidal melanocytes were morphologically and morphometrically examined in three populations of pigs (young, pregnant and aged), that were maintained on either control (C) or low zinc (LZ) diets. In C groups, the typical melanosomes decreased in size with age, although a subpopulation of larger melanosomes occurred in the oldest group. In contrast, the melanosomes of the animals on LZ diets increased in size significantly in the adult groups. The melanosomes in the pregnant and aged groups were 65% and 30–40% greater than those of the age-matched C groups. Extremely large melanosomes were frequently encountered in adult LZ choroidal melanocytes. Melanogenesis of these large bodies included the formation of one or more outer shells. Fusion of adjacent large melanosomes was also observed. Melanolysosomal-like bodies were observed, particularly among the pigmented cells in the large blood vessel region of C and LZ adults. Melanin dynamics, i.e. its production and breakdown, occurred within choroidal melanocytes throughout much of the lifespan of the pig. This dynamic was greatly influenced by low zinc nutrition, resulting in unusual and aberrant melanin activity.     

The influence of aging and low zinc nutrition on the choroid in the pig: I. The melanocyte

The effects of low zinc nutrition and aging on central choroidal melanocytes were examined in the pig. Three populations of pigs (young, pregnant and aged), were maintained on either control (C) or low zinc (LZ) diets. Twenty-five weanling boars were sacrificed at 2, 4, 8, 10, and 12-month intervals, and nine pregnant sows and eight aged sows were sacrificed after a 6-month interval. Melanocytes of the central choroid were morphologically and morphometrically examined. The melanocyte was found to be conservative in its form, which was mostly elliptical longitudinal profile, throughout the different age populations that were fed the C diet. Morphometric observations revealed that this cell type increased in size in the oldest animals, having been 40% greater than that in the younger two populations. However, the overall percentage area occupied by melanocytes remained the same throughout all age groups. In the animals that were fed the LZ diets, a large subpopulation of choroidal melanocytes was oval to round in shape in the pregnant and aged groups. Many members of this subpopulation possessed less opaque pigment than the elliptically shaped cell. Measurements of the size and percentage area occupied in these oldest groups increased significantly. In addition to the change of size, shape and melanin opaqueness, unusually large melanosomes were consistently observed in the pregnant and aged LZ groups. Low zinc nutrition had a remarkable age-related impact on the usually quiescent melanocyte.     

Evaluation of the flukicide treatment policy for dairy cattle in Galicia (NW Spain)

Fasciola hepatica infection is an important cause of lost productivity in livestock worldwide. Effective control of fasciolosis is difficult, especially in milking cows, which can only be treated during dry periods, a control strategy that has not been yet evaluated. In this cross-sectional study, we investigated the effect of the type of flukicide treatment on the prevalence and intensity of infection in dairy cattle from Galicia, an area where fasciolosis is endemic and which is also the main milk-producing region in Spain. Faecal samples were taken from 5188 dairy cows on 275 randomly selected farms for measurement of the concentration of F. hepatica coproantigens by a monoclonal antibody based immunoassay (MM3-COPRO ELISA). On the same day as the sampling, each farm owner/manager was questioned about the types of treatment used on the farm. Three groups of farms were considered according to the fasciolicide treatment: (A) flukicides were not used, (B) an anthelmintic effective against mature stages of flukes was used (albendazole or netobimin) and (C) a fasciolicide effective against immature and mature stages was used (triclabendazole: TCBZ). Results indicated that 16.0% (832/5188) cows from 61.1% (168/275) herds were infected by F. hepatica. The mean coproantigen concentration in infected herds was 13.0ng/ml (range 0.9-112.6ng/ml). The highest individual concentration recorded was 496.6ng/ml. Herd and within-herd prevalences of F. hepatica were similar in all three groups, but surprisingly, individual prevalence and antigen concentration were higher in Group C (p<0.05). The percentage of farms with within-herd prevalences >25% was very high in all three groups, and no significant differences were observed. In contrast, the percentage of herds with mean antigen concentrations >20ng/ml was significantly lower (p<0.05) in Groups A and B (14.4% and 14.9%, respectively) than in Group C (50.0%). The proportion of herds that exceeded both limits (25% for prevalence and/or 20ng/ml for coproantigen concentration) was also significantly higher (p<0.05) in Group C than in untreated animals (Group A). The survey showed that most dairy farmers are unaware of the existence of F. hepatica infection on their farms, and treatments, when given, are administered without prior diagnosis. Treatment with TCBZ administered only at drying off did not show advantages over other measures including no treatment, or treatment with other benzimidazoles. Consequently, TCBZ should only be used to treat individual animals after correct diagnosis of the infection, and correct management measures taken to control re-infection.     

锌对断奶后不同阶段仔猪抗菌肽PR-39 mRNA表达的影响

72头36日龄杜长嘉(♂杜洛克×♀长嘉)断奶仔猪按体重相近要求随机分成3个处理组,每个组设3个重复,每个重复8头猪(公母各半)。对照组(处理1)饲喂不添加任何锌源的基础饲粮(DE 13.2 5 MJ/kg,CP 18.5 % ) ,处理2和处理3分别饲喂添加硫酸锌(10 0 mg/kg Zn)和氧化锌(30 0 0 mg/kg Zn)饲粮。试验分两个阶段进行,分别在5 8日龄和80日龄屠宰取样。本实验室根据已报道的猪抗菌肽PR- 39和看家基因β-肌动蛋白(β- actin)基因序列,分别设计PR- 39和β- actin的引物,探讨了PCR体系中适宜的Mg Cl2 浓度、循环次数,以及两对引物间竞争情况。以此构建一优化的半定量RT- PCR法,以β- actin为内标,研究锌对不同阶段断奶仔猪抗菌肽PR- 39基因表达的影响。结果显示,5 8日龄仔猪试验组与对照组相比,高氧化锌组(30 0 0 mg/kgZn)显著提高了抗菌肽PR- 39基因的表达量,提高量为378.2 6 % (P<0 .0 1) ,硫酸锌组(10 0 mg/kg Zn)使抗菌肽PR- 39基因的表达也分别提高了38.4 % ,但统计结果差异不显著。80日龄仔猪试验组与对照组相比,高Zn O组(30 0 0 mg/kg Zn)中PR- 39基因表达量比对照组分别提高4 .5 2 % ,统计结果无显著变化,Zn SO4 组(10 0 m g/kg Zn)中PR- 39基因表达量比对照组提高了5 1.97% ,统计结果差异显著     

Influence of Age and Breed on Natural Bovine Fasciolosis in an Endemic Area (Galicia,NW Spain)

An analysis was undertaken of the effect of breed and age on bovine fasciolosis using antibody and antigen detection ELISAs. A total of 84.3% of the 1284 serum samples examined had positive antibody values and 20.4% exhibited antigenaemia. The seroprevalence of antibodies in crossbred cattle was higher than that in autochthonous Rubia Gallega, Friesian or Brown Swiss cows. The highest percentage antigenaemia occurred in the Brown Swiss cattle, but the breed differences were not statistically significant. Cattle aged 3–5 years had the highest antibody and circulating antigen prevalence and the age differences were significant. It was concluded that the apparent influence of breed was probably closely associated with the husbandry system. The autochthonous Rubia Gallega may be better adapted to fasciolosis as its percentage of antigenaemia was the lowest.     

高锌日粮对奶牛产乳性能及血锌含量的影响

选择经产期和产奶量相近的健康中国荷斯坦奶牛50头,完全随机分成5组,每组10头,分别饲喂基础日粮及添加150mg/kg和300mg/kg的有机锌和无机锌日粮。结果表明:1)添加150mg/kg和300mg/kg的锌对牛奶中乳脂率、乳蛋白、乳糖和非脂固形物(SNF)含量无显著影响(P>0.05);2)无机锌对产奶量无显著影响(P>0.05),而添加有机锌则可显著提高奶牛产奶量(P<0.05);3)高锌可极显著(P<0.01)提高血锌和乳锌含量,而且血锌与乳锌之间存在线性相关(r=0.627,n=50)。     

微量元素铁、铜、锌、硒对肉牛作用的研究进展

微量元素在肉牛日粮营养中具有重要的作用,本文对肉牛日粮中需要补充的铁、铜、锌和硒的生理功能、相互作用、促生长效果和适宜添加量的研究进展进行综述,以期为肉牛精细化养殖做好日粮配方提供依据。     

Selenium and zinc concentrations in kidney, liver and muscle of cattle from different parts of Norway.

Cattle slaughtered in four different parts of Norway have been examined with respect to selenium and zinc content in kidney, liver and muscle. Highest selenium concentrations were found in kidney and lowest in muscle. In spite of extensive use of standardized concentrates, geographic differences were detected with regard to selenium tissue levels, animals from the southeastern inland region having the lowest levels. According to other workers, this region has low-selenium humus soils, and selenium responsive diseases among young ruminants have been of considerable importance, especially when concentrates had not been given during winter feeding. The recorded tissue selenium levels are compared to other workers’ proposals for normal values. All animals examined in this study seem to be well within healthy limits. Kidney, liver and muscle from cattle are good sources of selenium with respect to human nutrition.As far as zinc concentrations are concerned, muscle has the highest and kidney the lowest levels. Geographic differences were found, and individuals from the midland and northern coastal regions have the highest zinc tissue levels. Cattle from the northern coastal region seems to have especially high zinc concentrations in the organs.     

Prevalence of serum antibodies to Mycobacterium avium subsp. paratuberculosis in cattle in Galicia (northwest Spain)

Prior to establishing a control and prevention program for Johne's disease in cattle in Galicia (northwest Spain), a survey was conducted to estimate the prevalence of the disease. For this survey, 61,069 animals of at least 1-year of age from 2735 randomly selected herds were bled and samples analyzed with a commercial ELISA. The estimated true individual-level prevalences – assuming the manufacturer's reported test sensitivity of 48.5% and specificity of 98.9% – were 3.02% in dairy cattle, 1.03% in beef cattle and 2.83% in animals from farms with both dairy and beef cattle. True herd prevalences (with herds declared positive if one or more animals tested positive) were 10.69% for dairy herds, 0% for beef herds and 2.71% for mixed herds. When herds were declared positive if at least two animals tested positive, true herd prevalences were 14.75% for dairy herds, 1.47% for beef herds and 12.01% for mixed herds. Assuming a higher specificity of 99.4%, true individual-level prevalences increased to 4.03% in dairy herds, 2.07% in beef herds and 3.84% in mixed herds. Herd prevalences were 27.77%/18.79%, 2.78%/2.40% and 5.70%/12.24% (using the one/two-animal cut-offs) in dairy, beef and mixed herds, respectively. In conclusion, these results seem to indicate that a small percentage of cows and a rather high percentage of dairy herds in this region are MAP-seropositive.     

Failure of zinc supplementation to prevent severe facial eczema in cattle fed excess copper

CASE HISTORY: A 400-cow dairy unit in the Waikato suffered a severe outbreak of facial eczema (FE) despite consistent zinc supplementation and significantly elevated serum zinc concentrations.

CLINICAL FINDINGS: FE prevention had begun in mid-January 2006, via zinc sulphate supplementation in the water. Photosensitisation was reported on 06 April, contemporaneous with a marked increase in the number of Pithomyces chartarum spores in pasture samples. Within 10 days of this first clinical case, 100 affected cows had been dried off, eight of which subsequently died or were culled. Blood samples were collected from ten affected cows; all had serum zinc concentrations >17 µmol/L, and eight had gamma-glutamyl transferase (GGT) activities >200 U/ml, indicating that the photosensitisation was secondary to liver damage, i.e. probably FE. Further investigation identified that this herd had been receiving excess copper supplementation; 4/6 culled cows had liver copper concentrations within or above the marginal range for copper toxicity.

DIAGNOSIS: Severe FE despite zinc supplementation that increased serum zinc concentrations above recommended levels

CLINICAL RELEVANCE: As zinc supplementation significantly reduces apparent copper status, copper supplementation is often used to counteract this. Previous excess copper intake may reduce the efficacy of zinc in preventing FE, thus copper intake should be assessed prior to the start of zinc supplementation.     

Prevalence and intensity of infection of Cryptosporidium spp. and Giardia duodenalis in dairy cattle in Galicia (NW Spain)

Faecal samples were collected from 734 cattle selected at random from 60 dairy farms in Galicia (NW Spain). The animals studied were classified into 12 age groups: <1 month (53); 1-5 months (30); 6-11 months (31); 12-16 months (72); 17-20 months (64); 21-24 months (96); 3 years (94); 4 years (74); 5 years (67); 6 years (67); 7-8 years (63) and 9-13 years (23). Oocysts of Cryptosporidium spp. were identified in 104 animals (14.2%) distributed throughout all of the age groups and from 40 different farms (66.7%). The percentage of cattle infected ranged between 58.5% in calves <1 month and 7.9% in 7 to 8-year-old cows, i.e. the percentage of infection decreased significantly (P < 0.05) with increasing age. The intensity of infection in animals older than 1 month ranged between 10 and 5924 oocysts/g of faeces and there were no significant differences between the different groups. Cysts of Giardia duodenalis were identified in 221 animals (30.1%) from 56 farms (93.3%). The parasite was detected in all age groups, at rates of infection ranging between 21.8% (9-13 years) and 56.7% (1-5 months), although these differences were not statistically significant. The intensity of infection ranged between 7 and 15 412 cysts/g of faeces, with the number of cysts shed being significantly higher (P < 0.05) in calves <1 month than in calves aged 1-5 months. Significant associations between parasitisation by Cryptosporidium spp. or G. duodenalis and the consistency of the faeces were only found in calves aged <1 month and 1-5 months. Concurrent infections were more prevalent in the groups of calves of 1-5 months (23.3%) and 6-11 months (25.8%).     

日粮锌源和锌水平对断奶仔猪血清及组织铜、铁、锌沉积的影响

选用临床检查健康的(26±2)日龄"杜×长×大"三元杂交断奶仔猪100头,按体质量和性别随机分为5组,每组20头,分别饲喂基础日粮、基础日粮+2000mg/kg氧化锌、基础日粮+3000mg/kg氧化锌、基础日粮+250mg/kg蛋氨酸锌、基础日粮+500mg/kg蛋氨酸锌。试验期14d。于断奶后0,7,14d,经前腔静脉采血,用原子吸收光谱仪检测血清中铜、铁、锌水平。试验结束时,每组选5头仔猪放血致死,取心、肝、肾、脑、脾、胸腺组织,测定铜、铁、锌含量。结果显示,仔猪断奶后,血清中铜、锌水平显著或极显著下降(P0.05或P0.01);添加不同锌源和锌水平的高锌日粮能提高断奶仔猪肝、肾、脑、血清锌的含量,显著或极显著降低仔猪血清铜和心、胸腺铜以及脾铁水平(P0.05或P0.01),对血清铁及其他组织铁含量无明显影响。这表明高锌日粮能增加断奶应激仔猪体内锌水平,降低部分组织中铜、铁含量。     

断奶仔猪料中添加甲酸钙、杆菌肽锌及高铜的效果

试验采用Ｌ９（３４）正交设计，将３５日龄断奶的２７窝仔猪共２０７头，以窝为单位分成９组。试验因子为３个不同水平的甲酸钙（０，１，２％），杆菌肽锌（０，６３，１２６万效价单位／吨），及铜（０，７５，１５００ｐｐｍ）。４５～７５日龄期间进行饲养试验。结果表明，在４５～７５日龄期间，添加甲酸钙极显著影响（降低）猪的平均日增重（Ｐ＜０．０１）和经济效益；添加杆菌肽锌有利于仔猪的平均日增重，且以添加６３万单位／吨为宜。加铜后不显著影响猪的平均日增重（Ｐ＜０．１）。建议４５～７５日龄期间不再添加酸化剂。     

铜缺乏对奶牛肝脏金属硫蛋白代谢的影响

为阐明金属硫蛋白在铜缺乏奶牛肝脏中的代谢特征 ,选择铜缺乏区有明显临床症状的奶牛 6头 ,采集肝脏样品后用差速离心法分离肝脏金属硫蛋白 ,以Sephadex G75进行层析纯化 ,测定各部分洗脱液中金属元素铜、锌、铁、镁的含量。将 6头健康奶牛的肝脏样品作为对照。试验结果表明 ,发病奶牛肝细胞浆Sephadex G75柱层析洗脱液中铜、铁含量峰值显著高于健康奶牛 ,且在后面部分层析液中出现小峰 ;发病奶牛肝细胞浆金属硫蛋白 (MT)层析液锌、镁含量曲线峰值宽阔且高于对照组 ,第 2峰形宽大且有前移现象。结论 :铜缺乏能够改变奶牛肝脏中金属硫蛋白的代谢     

The cumulative methane production from dairy cattle slurry can be explained by its volatile solid,temperature and length of storage

In order to refine the national estimate of methane emission from stored cattle slurry, it is important to comprehend the basic characteristics of methane production. Two dairy cattle slurries were obtained from livestock farms located in Hokkaido (a northern island) and Kyushu (a southern island). The slurries were diluted with water into three levels: undiluted, three times diluted, and 10 times diluted. Three hundred mL of the slurries were put into a bottle with a headspace volume of 2.0 L, which was filled with nitrogen gas and then sealed by butyl rubber. Four levels of temperature were used for incubation: 35, 25, 15 and 5 °C. The time course of the cumulative methane production per volatile solid (VS) was satisfactorily expressed by an asymptotic regression model. The effect of dilution on the methane production per VS was not distinctive, but that of temperature was of primary importance. In particular, higher temperature yields a higher potential production and a shorter time when the cumulative production reaches half of the potential production. The inclusive and simple models obtained in this study indicate that the cumulative methane production from stored cattle slurry can be explained by VS, temperature and length of storage.     

Assessment of zinc and copper status in weaned piglets in relation to dietary zinc and copper supply

The aim of the study was to determine the effect of weaning and the effect of increasing dietary zinc concentrations on the zinc and copper status of weaned piglets (study 1) and to study the effect of high concentrations of dietary zinc and/or copper on zinc and copper status of weaned piglets (study 2). Study 1 included 54 piglets (six litters of nine piglets). One piglet from every litter was killed 1 day before weaning. The remaining 48 piglets were allocated at weaning (28 days) to four dietary zinc treatments (100, 250, 1000 or 2500 ppm) and subsequently killed 1-2, 5-6 or 14-15 days after weaning. Study 2 included 48 piglets (six litters of eight piglets) allocated to four dietary treatments, consisting of low or high dietary zinc (100 or 2500 ppm) in combination with low or high dietary copper (20 or 175 ppm). All piglets in study 2 were killed 5-7 days after weaning. In both studies, the trace mineral status was assessed by zinc and copper concentrations and alkaline phosphatase (AP) activity in plasma and mucosal tissue. In study 2, lymphocyte metallothionein (MT) mRNA and intestinal mucosa MT mRNA concentrations were included as zinc status markers. The results showed that the zinc status, measured as zinc in plasma and mucosa, was not affected by weaning of the piglets. Plasma copper concentrations decreased during the first 2 weeks after weaning. High dietary copper concentrations did not affect the concentration of copper in plasma, but increased the concentration of copper in mucosa and the concentration of zinc in plasma. The dietary zinc treatments increased the zinc concentration in plasma as well as the zinc and MT mRNA concentration in mucosa. Lymphocyte MT mRNA concentrations did not reflect the differences in dietary zinc supplementation.