Effect of molecular weight and concentration of legume condensed tannins on in vitro larval migration inhibition of Haemonchus contortus

The effect of molecular weight of condensed tannins (CT) from a variety of warm-season perennial legumes commonly consumed by sheep and goats on anthelmintic activity has not been previously explored. The objectives of this study were to determine if molecular weight of CT from warm-season perennial legumes could predict the biological activity of CT relative to anthelmintic activity against ivermectin resistant L3 stage Haemonchus contortus (HC) using a larval migration inhibition (LMI) assay. A second objective was to determine if CT from warm-season perennial legumes possess anthelmintic properties against L3 stage (HC). Lespedeza stuevei had the greatest concentration of total condensed tannin (TCT; 11.7%), whereas, with the exception of Arachis glabrata, a CT-free negative control, Leucaena retusa had the least TCT (3.3%). Weight-average molecular weight of CT ranged from 552 Da for L. stuevei to 1483 Da for Lespedeza cuneata. The treatments demonstrating the greatest percent LMI were L. retusa, L. stuevei and Acacia angustissima var. hirta (65.4%, 63.1% and 42.2%, respectively). The ivermectin treatment had the smallest percent LMI (12.5%) against ivermectin resistant L3 HC. There was a weak correlation (R² = 0.34; P = 0.05) between CT M_W and percent LMI, suggesting that molecular weight of CT is a weak contributing factor to CT biological activity as it relates to LMI of L3 stage HC. L. stuevei, L. retusa and A. angustissima var. hirta STP5 warrant further evaluation of anthelmintic properties in vivo.     

3个品种鸭的屠宰性能及肌肉营养成分比较

将番鸭、樱桃谷鸭、高邮鸭饲养到70日龄屠宰。测定屠宰性能,同时取胸肉和腿肉测定营养成分。结果表明:樱桃谷鸭早期生长速度最快;番鸭是3个鸭品种中肉用性能最好的优质肉鸭,樱桃谷鸭的腿肉比例偏小,高邮鸭的胸、腿肌率均未达到优质肉鸭的要求。番鸭鸭肉中水分含量较高,樱桃谷鸭与高邮鸭鸭肉中脂肪含量较高。     

Comparison of the time required to administer three different fluke and worm combination products to commercial beef cattle at housing

Larger livestock units, a decline in the farm labor force, animal welfare concerns, and a trend toward more selective use of drugs have increased the focus on animal handling, time management, convenience, and compliance in administering veterinary therapeutics. This study was undertaken to quantify and compare the time needed to treat commercial beef cattle with three fluke and worm combination products with different administration profiles. Young beef cattle (n = 270) weighing approximately 400 kg were allocated to batches of five, which were randomly assigned to receive ivermectin + clorsulon injection, ivermectin + closantel injection, or levamisole + triclabendazole oral drench. The mean time needed to administer ivermectin + clorsulon (single injection) to five cattle was 31 seconds, which was significantly less than the 100 seconds needed for ivermectin + closantel (two injections) and the 126 seconds needed for levamisole + triclabendazole (P less than .001). Such quantitative data can allow for better planning and selection of parasiticide treatment approaches at the farm level.     

Dry Matter and Crude Protein Degradability of Four Parasitic Plants (Mistletoes) Associated with Browse Trees in Botswana

Four parasitic plants (Tapinanthus lugardii, Erianthenum ngamicum, Viscum rotundifolium and Viscum verrucosum) associated with browse trees in Botswana were evaluated for the degradability of their dry matter (DM) and crude protein (CP). All these plants have high levels of crude protein, ranging from 144.5 to 163.4 g/kg DM, with a significant (p<0.001) difference in crude protein content between the plants. The rate of degradation of DM was highest for V. rotundifolium (0.197 h⁻¹) and lowest for E. ngamicum (0.031 h⁻¹). The two Viscum species had the highest effective DM degradability at an outflow rate of 0.05%. The rate of degradation of crude protein was highest for V. rotundifolium (0.144 h⁻¹) and lowest for T. lugardii (0.0346 h⁻¹). The effective degradability (ED) of crude protein was highest for V. rotundifolium at 0.03 and 0.05 h⁻¹ outflow rates. T. lugardii and E. ngamicum had an apparently low effective degradability, but this may result from an association of their protein with tannins, which would be able to supply amino acids in the small intestine after dissociation due to the abomasal pH. This revised version was published online in July 2006 with corrections to the Cover Date.     

Influence of phosphatic fertilization on the yield and chemical composition of grass pasture

While the distribution of P fertilizer had an insignificant influence on the DM production of a grass pasture over a three‐year period, the level of both N and P was highly significant. Growth patterns were unaffected by any of the fertilizer treatments and would appear to be determined primarily by environmental and genetic factors. With respect to crude protein and phosphorous content of the herbage this was determined primarily by the level of N and P fertilization, although the distribution of P in split applications tended to improve P content in the late summer.     

Impact of different approaches to calculate the economics of disease in pig farming

Diagrams for analyzing the economics of sow and fattening farms are described and discussed. The diagrams are used to quantify the economic significance of a change in technical results for pig farms in the Netherlands. Sensitivity analyses show the importance of taking into account feed savings of piglets and sows due to, for instance, less litters per sow per year. To see whether there was an effect of the economic environment and the structure of the fanning system, the same calculations were carried out for Minnesota (USA). The economic effect of a change in results (e.g. days open) was smaller for Minnesota, but economic effects were similarly influenced by specific factors, such as feed intake and price. Subsequently, several scientific publications on the estimation of the costs of Aujeszky's disease in pigs were compared with respect to the economic methods used and the outcomes obtained. Because of different estimation procedures, the costs of the disease varied significantly. Differences are mainly due to the loss items that were taken into account, the way the loss items were calculated and the structure of the farming system that was included. There is a need for a standardized framework of how to conduct a sound economic evaluation, in order to make the outcome of different calculations more comparable and interpretable.     

Using indirect ELISA to assess different antigens for the serodiagnosis of Fasciola gigantica infection in cattle, sheep and donkeys

An indirect enzyme-linked immunosorbent assay (iELISA) was evaluated for its diagnostic capability in detecting antibodies against Fasciola gigantica infection in cattle, sheep and donkeys sera using crude worm, excretory–secretory and glutathione S-transferase antigens prepared from adult liver fluke. Presence of F. gigantica worms at post-mortem examination of cattle, sheep and donkey’s livers was taken as a gold standard for the evaluation of the assay. The diagnostic sensitivity, specificity and accuracy percentages of iELISA were determined for each antigen. Excretory–secretory antigen gave the best results for the serodiagnosis of F. gigantica infection in cattle, sheep and donkeys using iELISA with diagnostic sensitivity percentages of 93.3%, 94.9% and 93.3%, respectively, while the specificity percentages were 96.7%, 97.2% and 96.3%, respectively, whereas the accuracy percentages were 95%, 96% and 95.7%, respectively. The diagnostic sensitivity percentages of iELISA using crude worm antigen were 96.7%, 100% and 93.3%, respectively, while the specificity percentages were 80%, 83.3% and 85.2%, respectively, whereas the accuracy percentages were 88.3%, 86.7% and 87%, respectively. The diagnostic sensitivity percentages of iELISA using glutathione S-transferase antigen were 66.7%, 71.8% and 60%, respectively, while the specificity percentages were 70%, 77.8% and 77.8%, respectively, whereas the accuracy percentages were 68.3%, 74.7% and 73.9%, respectively. Conclusively, excretory–secretory antigen dependent iELISA can be used as a reliable serodiagnostic test for F. gigantica infection in cattle, sheep and donkeys.     

Proanthocyanadin (condensed tannin) content of Brachystegia spiciformis browse harvested at different stages of growth from three sites in Zimbabwe

The extractable and insoluble (bound to protein or neutral detergent fibre [NDF] proanthocyanadin (PA) of the tree species Brachystegia spiciformis (Musasa) harvested at different stages of growth from three sites with different soil types in Zimbabwe was analysed by the n-butanol-HCl method. Brachystegia spiciformis samples from one site showed significantly lower (P < 0.05) PA values than those from the other two sites. Higher (P < 0.01) proportions of insoluble PA (insoluble PA/total PA) were observed in leaves than in twigs. Substantial levels of PA were detected as bound tannins, ranging from 470–804g kg^?1. These results suggest that measurement of bound condensed tannin is necessary when identifying forages containing condensed tannins. The higher contents of PA in the leaves that were harvested when mature than in young leaves could explain why animals prefer eating young rather than mature leaves of B. spiciformis.     

Agreement among three different equine venipuncture sites with regard to measurement of packed cell volume and total solids

The primary objective of this study was to determine the agreement between the packed cell volume (PCV) and total solids (TS) values in blood collected from the jugular vein (JV) in comparison with the cephalic vein (CV) and the transverse facial venous sinus (TFVS) in healthy adult horses. A total of 72 samples were taken from 24 horses. We found high agreement that reflects no clinically relevant differences between the PCV and TS values obtained from the CV or the TFVS in comparison with the JV in standing healthy adult horses.     

Seasonal diet composition and forage selectivity of Boer goats in a semi-arid gypsophilous grassland

Botanical and chemical compositions of Boer goat diets, determined with repeated collection of forage samples taken from the goat’s mouth, were studied in a gypsophilous grassland during four seasons of the year. Ten pluriparous goats were used to collect selected forage species. Shrubs were a minor dietary component throughout the year (<7.5%). Goats selected more (p?<?0.01) grass during autumn and winter (34.2–37.8%) than during spring (21.2%) and summer (29.0%). During all seasons goat diets were dominated by forbs (>59%). Diets were lowest (p?<?0.05) in percentage of crude protein during spring, summer and autumn (13.2?±?3.5, 13.2?±?2.4 and 14.2?±?3.9, respectively) than winter (17.5?±?2.9) with levels above the recommended quantities for goats throughout the year. In vitro dry matter digestibility of forages selected by goats did not differ between seasons (range 47.4–53.3%). It was concluded that in this particular ecosystem goats preferred forb species over grasses across all seasons. In addition, goats maintained relatively stable diet quality by forage-class mixing of diets.     

饲料中不同水平的蛋白质和脂肪对红笛鲷幼鱼生长和肌肉成分的影响

本文研究了饲料中不同水平的蛋白质和脂肪对初重(0.44±0.10)g红笛鲷幼鱼的存活率、生长(体长、体重和增重率)、蛋白质效率、饵料系数、肌肉成分和肝指数的影响。试验采用3×3因子设计,蛋白质设48%、51%和54%三个水平,脂肪设9%、12%和15%三个水平,共9组。试验期为60d。结果表明,饲料中蛋白质和脂肪含量分别为54%和12%时,红笛鲷体长、体重和增重率达到最大值,而饵料系数最低;蛋白质和脂肪含量分别为51%和9%时,红笛鲷的体蛋白蓄积量最高,而体脂含量最低。从增重率、饵料系数和鱼体品质综合考虑,饲料中蛋白质和脂肪的适宜量为54%和12%。     

Chemical composition and in sacco dry matter degradability of residue and by-products of palm fruit processing in the rumen of steers

The nutritive value of residue (palm calyx leaves (PCL)) and by-products (palm press fiber (PPF) and palm oil sludge (POS)) of palm fruit processing were studied through analysis of their chemical components and degradability of their dry matter (DM) in the rumen of steers. Chemical analysis showed that the materials have similar organic matter components (mean = 95.2%), while crude protein (CP, g/100 g) and metabolisable energy (ME, MJ/kg DM) were highest in POS (10.02 and 9.43), followed by PPF (7.02 and 8.61) and least in PCL (5.42 and 8.04). An opposite trend of CP and ME was noticed in NDF and ADF contents, being 61.53 and 49.11% in PCL, 44.84 and 32.08% in PPF and 25.35 and 20.29% in POS. Mineral contents showed that PPF and POS had the lowest and highest concentration, respectively, of Mg (0.07 vs. 0.11%), Cu (58.5 vs. 143.9 mg/kg) and Fe (1374.5 vs. 4086.0 mg/kg). Dry matter degradation characteristics and effective degradability varied significantly ( P  < 0.05) and were consistently highest in POS and least in PCL. Results have generally shown that the residue and by-products could be ranked for their potential feeding value as POS > PPF > PCL. It is concluded that POS and PPF can be harnessed directly as feed resources for ruminant animals, while PCL will require some treatments to enhance its nutritive value in ruminants.     

Chemical composition, in vitro digestibility and gas production of straws from different varieties and accessions of chickpea

Chemical composition, in vitro digestibility and gas production of straw from four different varieties of Kabuli chickpea (Cicer arietinum) were studied. Kinetics of fermentation of straws from 19 different accessions of chickpea was also evaluated using gas production technique. Significant difference (p < 0.05) was observed in the yield of straw [from 1041 to 1174 kg dry matter (DM)/ha] from different varieties. The proportion of seed/straw from different varieties varied from 0.61 to 0.93. Crude protein, neutral detergent fibre and acid detergent fibre content of straw ranged from 28.1 to 35.8, 598.6 to 645.4 and 459.2 to 473.4 g/kg DM respectively. Organic matter digestibility was different (p < 0.05) among varieties and varied from 471.4 to 535.5 g/kg DM. Potential gas production (A), the rate constants (c and d) and lag times of straws from different chickpea varieties were not different (p > 0.05). However, the rate constants (c and d) and lag times were different (p < 0.05) among accessions. Potential gas production (A) differed (p < 0.05) approximately twofold among different accessions. The results emphasized that in any evaluation of chickpea varieties or accessions, where straw of this legume seed is used as an animal feed, not only seed yield but also yield and quality of straw should be taken into consideration.     

日粮粗蛋白水平对反刍动物瘤胃发酵和微生物区系影响的研究进展

蛋白质是反刍动物的必需营养素,不同蛋白质水平日粮使瘤胃发酵参数发生改变。本文就不同蛋白水平日粮对瘤胃pH、NH3-N、VFA的浓度和瘤胃微生物区系组成的影响研究进展情况进行综述,为进一步开展相关研究奠定基础。     

不同代谢能和粗蛋白质水平对合浦鹅日粮养分消化率及生长性能的影响

本文旨在研究日粮不同代谢能和粗蛋白质水平对合浦鹅日粮干物质、粗蛋白质、粗脂肪、粗纤维、钙和磷等养分的消化率及生长性能的影响.将120只28日龄的合浦鹅随机分成6个组,进行2个饲养和消化试验:试验1组饲喂粗蛋白质水平为15.10%,代谢能水平分别为10.03、11.00和11.85 MJ/kg的3种日粮;试验2组饲喂代谢能水平为11.50 MJ/kg,粗蛋白质水平分别为12.50%、14.85%和17.83%的3种日粮.用4 mol/L HCI ALA方法测定日粮的养分消化率.结果表明:粗蛋白质水平为15.10%和代谢能水平为10.03 MJ/kg的日粮,具有较高的养分消化率,但不同代谢能水平对试鹅的生长性能影响差异不显著(P>0.05);代谢能水平为11.50 MJ/kg和粗蛋白质水平为12.50%的日粮也具有较高的养分消化率,但不同粗蛋白质水平对试鹅的生长性能影响差异也不显著(P>0.05).因此,28日龄以后的合浦鹅的日粮粗蛋白质和代谢能水平分别为15.10%和10.03 MJ/kg,或分别为12.50%和11.50 MJ/kg时,均具有较高的养分消化率,但对合浦鹅的生长性能无显著影响.     

Chemical composition of alfalfa silage with waste date and its feeding effect on ruminal fermentation characteristics and microbial protein synthesis in sheep

This study was conducted to evaluate the effect of feeding ensiled alfalfa with waste date on ruminal fermentation characteristics, microbial protein synthesis, protozoa population and blood parameters in sheep. Eight rams were used in a 2 × 2 change over design. Each experimental period consisted of 21 days including 16 days for adaptation and 5 days for sampling. For ensiling, fresh alfalfa (Medicago sativa L.) with different levels of waste date (Phoenix dactylifera L.) were mixed together and ensiled in 100‐l containers for 45 days. Chemical composition of silages such as dry matter (DM), crude protein, NH₃‐N, organic matter, NDF, ADF and pH were determined. Then, it was used as 30% (DM basis) in diets. The experimental diets were as follows: (i) control (diet containing alfalfa silage without waste date), (ii) diet containing alfalfa silage with 5 g waste date/95 g DM, (iii) diet containing alfalfa silage with 10 g waste date/90 g DM, and (iv) diet containing alfalfa silage with 15 g waste date/85 g DM. The results of this experiment showed that adding waste date to alfalfa during ensiling, improved silage quality, DM and energy level. Total protozoa population and all of holotrich, cellulolytic and entodinia in rumen fluid were increased linearly by increasing the level of waste date. Nitrogen (N) intake, urinary N excretion and nitrogen retention were affected by dietary treatments. Also, allantoin, uric acid, total purine derivatives, microbial protein synthesis, cholesterol level and blood urea nitrogen were significantly different. In conclusion, direct ensilage of alfalfa can be attained by mixing 15 g waste date/85 g DM and positive associative effects such as increased metabolizable energy (ME) and silage quality occurred.     

高温干旱胁迫下三个多年生黑麦草品种叶绿体和线粒体超微结构的变化

以多年生黑麦草的3个草坪型品种爱神特、百舸和球道为试验材料,研究了在高温和干旱胁迫下,各品种叶肉细胞叶绿体和线粒体等超微结构的变化情况。结果表明,35℃连续高温胁迫下3个品种的叶绿体均膨大变圆,并向细胞中央靠拢,且叶绿体内部分布有一定数目的脂质球体;PEG-6000(w/v)溶液(浓度为25%)处理的干旱胁迫下以球道的叶绿体结构受干旱胁迫伤害程度较重,出现基粒和被膜轻度破损,片层膨胀分化或溶解消失。高温干旱胁迫下3个品种的线粒体形态变化不甚显著,但其数量均有所增加,且3个品种叶肉细胞线粒体对高温干旱胁迫的耐受性均强于叶绿体。爱神特对高温干旱胁迫处理的耐受性相对较强,球道和百舸的耐热抗旱性较弱,但两者差异不明显。