日粮不同苏氨酸水平对仔猪生产性能和血液生化指标的影响

在必需氨基酸模式为赖氨酸（ＬＹＳ），蛋氨酸（ＭＥＴ）＋胱氨酸（ＣＹＳ）：色氨酸（ＴＲＰ）：异亮氨酸（ＩＬＥ）＝１００：６５：２０：６５的基础日粮中（含苏氨酸０．５４４％）．分别添加Ｌ－苏氨酸０、０．０６８％、０．１３６％．０．２０４％、０．２７２％构成５种苏氨酸水平。将４０头２８日龄断奶的大白仔猪，随机分为５组，进行了为期２８天的对比实验。发现不同苏氨酸水平时仔猪的采食量、日增重和饲料转化率都有显著影响。其中日粮苏氨酸水平＊为０．７４８％时，仔猪的采食量、体增重、血清谷丙转胺＊酶最高，饲料转化率和血清尿素氮最低。仔猪的血清胆＊固醇和甘油三酯在苏氨酸水平为０．６８％时最低，而碱＊性磷酸酶最高。结果表明，有利于仔猪最佳生产性能的＊必需氨基酸模式力：ＬＹＳ：ＭＥＴ＋ＣＹＳ：ＴＨＲ：ＴＲＰ：＊ＩＬＥ＝１００：６５：６５：２０：６５。     

苏子饼日粮对产蛋鸡的饲喂效果

４００只３７周龄产蛋鸡按随机法等分为４组,试验期２０周,观察并测定１０％、１５％、２０％苏子饼日粮的饲喂效果。试验结果表明：１０％、１５％日粮组鸡产蛋性能与“玉米＋豆粕”型日粮对照组无明显差异（Ｐ＞０．０５）,鸡血浆总蛋白、球蛋白、Ａ／Ｇ、ＢＵＮ、ＧＰＴ、血液ＵＡ无明显变化,肝、肾、甲状腺未出现异常病变,而血清ＩｇＧ、ＩｇＭ明显上升（Ｐ＜０．０５）：２０％日粮组鸡产蛋量下降,料蛋比上升,每ｋｇ鸡蛋饲料成本增加,血浆ＢＵＮ、ＧＰＴ、血液ＵＡ明显下降（Ｐ＜０．０５）。由此认为：苏子饼在产蛋鸡日粮中占１５％是可行的。     

饲粮类型和蛋白质水平对早期断奶仔猪生产性能的影响

选４８头２８±２日龄断奶仔猪（平均体重约５．５千克），随机分成８组，采用２×４设计研究２种饲粮类型与４个粗蛋白质（ＣＰ）水平（２２、１８、１７和１４％）对仔猪生产性能的影响。试验结果显示：①低蛋白质饲粮使仔猪血浆尿素氮（ＰＵＮ）含量和腹泻指数显著降低（Ｐ＜０．０５或０．０１）。②采食全植物蛋白型饲粮的仔猪，其平均日增重（ＡＤＧ）和平均日采食量（ＡＤＦＩ）低于（Ｐ＜０．０１）采食复合蛋白型饲粮的仔猪。前者的料肉比（Ｆ／Ｇ）趋于高于后者，但差异不显著（Ｐ＞０．０５）。前者的ＰＵＮ含量高于（Ｐ＜０．０１）后者。③对于ＡＤＧ、ＡＤＦＩ和ＰＵＮ指标，存在饲粮类型×ＣＰ水平的交互作用（Ｐ＜０．０５或０．０１）。④全植物蛋白型饲粮和复合蛋白型饲粮取得最大日增重的ＣＰ水平（％）分别为１８．９和１９．９。试验结果表明，复合蛋白型饲粮的饲养效果优于全植物蛋白型饲粮。饲粮类型不同，蛋白质的适宜水平也不同。     

饲粮蛋白质水平对早期断奶仔猪大肠蛋白质腐败作用和腹泻的影响

选５７头２８日龄断奶仔猪（平均体重约４．５ｋｇ），研究饲粮粗蛋白质（ＣＰ）水平对早期断奶仔猪大肠蛋白质腐败作用和腹泻的影响。结果显示：（１）饲粮ＣＰ水平分别与仔猪的ＣＰ、未消化ＣＰ日摄入量，结肠内容物中大肠杆菌、挥发性盐基氮（ＶＢＮ）和氨氮（ＡＮ）含量，以及腹泻指数之间存在显著（Ｐ＜０．０５）或极显著（Ｐ＜０．０１）的正相关。（２）结肠内容物中ＶＢＮ和ＡＮ含量分别与仔猪腹泻指数呈显著（Ｐ＜０．０５）的正相关。（３）饲粮ＣＰ水平分别与盲肠内容物中ＶＢＮ和ＡＮ含量之间的相关关系不显著（Ｐ＞０．０５）。（４）随着饲粮ＣＰ水平的升高，仔猪结肠组织病理变化亦增加。（５）与ＣＰ２０．４％的全植物蛋白型饲粮和ＣＰ１９．２％的复合蛋白型饲粮比较，低蛋白质氨基酸平衡饲粮（ＣＰ１６．５％）可有效地降低仔猪结肠内容物中ＶＢＮ和ＡＮ含量及腹泻指数。试验表明，饲粮ＣＰ水平对结肠蛋白质腐败作用可产生显著的影响。随着饲粮ＣＰ水平的升高，结肠内蛋白质腐败、结肠组织病理变化和仔猪腹泻指数均有增加。平衡饲粮氨基酸使ＣＰ水平降低可减少结肠内蛋白质的腐败和仔猪断奶后腹泻。     

早期断奶仔猪饲粮添加喷雾干燥血浆蛋白粉效果试验

从１２窝杜长大杂种仔猪选取８８头，２８日龄断奶，按体重、窝别分为两组，每组４４头，公母比例１∶１，预饲１０天，组平均体重９．５２ｋｇ，组间差异不显著（Ｐ＞０．０５），开始试验。试验组饲粮（添加喷雾干燥血浆蛋白粉，ＳＤＰＰ）组成（％）：玉米６４、豆粕１...     

饲粮蛋白质及赖氨酸水平对早期断奶仔猪胃肠道消化酶活性、大肠蛋白质腐败作用和腹泻的影响

试验采用早期断奶仔猪（２５±３日龄，平均体重６．７８ｋｇ），用简单的玉米 豆粕 鱼粉型日粮饲喂，研究了不同蛋白质水平（１８％，２０％）和赖氨酸水平（１．０％，１．３％和１．６％）对仔猪胃肠道内容物消化酶活力、结肠蛋白质腐败作用和腹泻的影响。试验结果表明：日粮蛋白质水平较高时（２０％），仔猪腹泻率提高，这与大肠腐败作用无关；高蛋白质水平导致了大肠细菌活动的加强和小肠液淀粉酶活力的下降；不同赖氨酸水平对以上观测指标无影响。     

猪育种进展及其发展趋势

哺乳母猪日粮含消化能１４．２１ＭＪ／ｋｇ，粗蛋白１６．３～１９．２％（随猪只日增重的不同而调整），赖氨酸０．８２～１．０３％（随猪只日增重的不同而调整）。加拿大提出的最低营养标准为：中猪（２０～６０ｋｇ）（见表３）；哺乳母猪合消化能１４．０００ＭＪ／ｋｇ，粗蛋白１６％，赖氨酸０．８％，钙０．９％，磷０．７％，ＶＡ７ ５００ＩＵ／ｋｇ、ＶＤ７５０ＩＵ／ｋｇ，ＶＥ３５ＩＵ／ｋｇ，胆碱６００ｍｇ／ｋｇ；生物素０．３０ｍｇ／ｋｇ。 猪育种的进展，有赖于遗传理论的创新和育种技术的改进，国际上以遗传学为理论指…     

断奶仔猪色氨酸需求参数的研究

试验选取６０头体重约８ｋｇ的三元杂交（杜×（大×长））断奶仔猪,随机分为５组,每组２个重复,分别饲喂色氨酸水平为０．１３０％、０．１５５％、０．１８０％、０．２０５％和０．２３０％的玉米———玉米蛋白粉型饲粮,以探讨断奶仔猪对色氨酸的需求参数。结果表明,在０．１３０％～０．２０５％的色氨酸水平内,随着饲粮中色氨酸水平的提高,仔猪的采食量、平均日增重和饲料转化率（Ｇ／Ｆ）都极显著提高（Ｐ＜０．０１）,采食每单位色氨酸所获得的体增重显著增加（Ｐ＜０．０５）,血清尿素氮浓度显著降低（Ｐ＜０．０５）。并且在饲粮色氨酸０．２０５％水平组,仔猪的各项指标最佳。但饲粮色氨酸０．２３０％水平组仔猪平均日增重又显著降低（Ｐ＜０．０５）,采食量和饲料转化率趋于降低（Ｐ＞０．０５）,采食每单位色氨酸所获体增重显著减少（Ｐ＜０．０５）,血清尿素氮浓度趋于升高（Ｐ＞０．０５）。以上结果提示,８～２０ｋｇ断奶仔猪获最佳生产性能的色氨酸需求参数为０．２０５％,饲粮中赖氨酸和色氨酸比例为１００：１８,相应的表观可消化色氨酸需求参数为０．１６３％。     

低聚果糖对仔猪生长性能的影响

６６头体重２０ｋｇ左右的仔猪分成２组，每组３个重复，每个重复１１头，分别饲喂含抗生素和低聚果糖日粮，研究其对仔猪生长性能的影响。结果表明，与抗生素组相比，添加０．１５％低聚果糖组日增重提高４．７１％（Ｐ〉０．０５），采食量提高５．８６％（Ｐ〉０．０５），饲料转化率降低１．２％（Ｐ〉０．０５），生物学综合评定值提高１．８％。由此可见，低聚果糖可替代抗生素应用于仔猪饲饲粮中。     

利用合成氨基酸配制仔猪低蛋白日粮研究

选择４２ 日龄平均体重１１．００ｋｇ 的三元杂交断奶仔猪３０ 头, 随机分为对照组和试验组。分别饲喂２０％ 蛋白日粮（ 含异亮氨酸０－６４ ％ ） 和低蛋白（１６ ％ ） 低异亮氨酸（０－４１％ ） 日粮＋ 合成异亮氨酸（０－２３） 。试验结果： 试验组日增重和日采食量分别比对照组提高６ ．２ ％ 和１８ ％ （Ｐ＞０ ．０５） ,饲料增重比降低３ ．７％ （Ｐ＞ ０ ．０５） 。血清尿素氮、总游离氨基酸、葡萄糖、胰岛素和皮质醇含量组间无显著差异。血清氨含量试验组显著低于对照组（Ｐ＜ ０ ．０５） 。结论：通过合理补充合成氨基酸, 能够节约仔猪日粮蛋白质４ ％ ; 通过补充合成异亮氨酸, 血球粉在断奶仔猪日粮中的用量可提高至６％ 而不会降低仔猪生长性能。     

白术、微米白术和白术多糖对断奶仔猪生长性能和肠道形态及微生态区系的影响

试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。     

Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia

Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal (GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April 2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes. But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia.     

Y‐chromosomal variation of local goat breeds of Turkey close to the domestication centre

Genetic variations in chromosome Y are enabling researchers to identify paternal lineages, which are informative for introgressions and migrations. In this study, the male‐specific region markers, sex‐determining region‐Y (SRY), amelogenin (AMELY) and zinc finger (ZFY) were analysed in seven Turkish native goat breeds, Angora, Kilis, Hair, Honaml?, Norduz, Gürcü and Abaza. A SNP in the ZFY gene defined a new haplotype Y2C. All domestic haplogroups originate from Capra aegagrus, while the finding of Y1A, Y1B, Y2A and Y2C in 32, 4, 126 and 2 Turkish domestic goats, respectively, appears to indicate a predomestic origin of the major haplotypes. The occurrence of four haplotypes in the Hair goat and, in contrast, a frequency of 96% of Y1A in the Kilis breed illustrate that Y‐chromosomal variants have a more breed‐dependent distribution than mitochondrial or autosomal DNA. This probably reflects male founder effects, but a role in adaptation cannot be excluded.     

A brief history of the prevention of infectious diseases by immunisations

Infectious diseases have always been a terrible scourge for humans. The appearance of these plagues, as they were called without distinction, was generally connected to various conditions: asters, climatic changes or religious reasons. The concept of contagious, and then infectious, diseases came slowly. Variolation, i.e. transmission of ‘virulent’ matter to induce a natural disease and the immunity against it, was brought from Constantinople to England by Lady Montague, in 1721. This ‘variolation’ technique was also often performed in veterinary medicine against diseases like sheep-pox or pleuropneumonia. As ‘vaccination’ is the term generally accepted for ‘immunisation’, variolation can be the word designating such a technique. The second period of the history of immunisation began, in 1880, with the studies of Pasteur and his collaborators. A great number of bacterial vaccines were developed: dead, live but attenuated or only parts of pathogens. The viruses were produced in animals, then in eggs and at last, in tissue cultures. Second generation vaccines appeared with genetic engineering: recombinant vaccines, vector vaccines, nucleic acids vaccines, and markers vaccines, among others. These novel technologies can permit the development of new ones and improve the quality of the vaccines already existing.     

Micronutrient Content of Certain Tropical Conventional and Unconventional Feed Resources of Southern India

The ash, silica and certain important micronutrients were estimated in conventional and unconventional feed and fodder resources available in Southern India. Commonly used dry roughages, such as paddy straw, ragi straw, maize kadbi/stalk, jowar kadbi/stalk, bajra stalk and wheat straw, were high in ash (9.9% +/- 0.77%) and silica (6.4% +/- 0.65%) and low in most of the other micronutrients, except iron, with paddy straw containing most silica (>9%). Cultivated non-leguminous (maize, jowar) and improved green crops (hybrid napier, guinea, green panic, NB-21, CO-1) were also high in ash (10.5% +/- 0.60% and 12.5% +/- 0.51%) but were moderate sources of P, Mg and Cu and good sources of Zn (98 +/- 13.8 ppm and 55 +/- 6.7 ppm). Leguminous green fodders (stylosanthus, lucerne, cow pea, soyabean) were excellent sources of Ca (1.9% +/- 0.16%), Mg (0.40% +/- 0.05%), Cu (30 +/- 5.2 ppm), Zn (121 +/- 14.7 ppm) and Fe (1234 +/- 166 ppm) and moderate sources of P. Mixed local grasses and weeds were high in silica (6.9% +/- 1.00%) but were good sources of Cu, Zn and Fe. Cereal grains (maize, wheat, rice, ragi) were low in ash (2.9% +/- 0.33%) and were relatively poor sources of Ca (0.22% +/- 0.03%), Mg (0.19% +/- 0.03%) and Cu (13 +/- 3.1 ppm). Pulses were low to medium sources of most minerals and good sources of Fe (1230 +/- 293 ppm). Oil seed cake/extractions (groundnut cake, cotton seed cake, soyabean meal, sunflower cake, safflower cake) and cereal by-products (rice polish, rice bran, wheat bran) were excellent sources of P (1.1% +/- 0.47% and 2.3% +/- 0.19%) and good sources of Zn (65 +/- 3.9 ppm and 66 +/- 10.7 ppm) and Fe (938 +/- 130 ppm and 662 +/- 126 ppm). Among the unconventional feeds screened, orange peel, sunflower heads, meat meal, rubber seed cake, spirulina algae and sea weeds contained plentiful Ca, Zn and Fe: tree leaves/top feeds (mulberry, erythrina, glyricidia, banana, subabul, groundnut haulms) were excellent sources of Ca (1.5% +/- 0.13%), Zn (120 +/- 22.9 ppm) and Fe (1033 +/- 133 ppm) but relatively poor sources of P. Soyabean husk, cocoa seed husk, rubber seed cake and meat meal were moderate to good sources of P (1.0% and 0.33%). The high Zn and Fe values of most feeds/fodders were probably due to soil contamination. This account of the micronutrient content of feed/fodder resources should help in strategic supplementation intended to alleviate local deficiencies.     

Bovine Mastitis in Selected Areas of Southern Ethiopia

A study on bovine mastitis, designed to determine the causal agents, prevalence of infection and impact of risk factors in three cattle breeds, was conducted in selected areas of southern Ethiopia. A total of 307 lactating and non-lactating cows, of which 162 were indigenous Zebu, 85 Jersey and 60 Holstein-Friesian, were examined by clinical examination and the California mastitis (CMT) test. Of these, 40.4% were positive by CMT and bacteriology for clinical or subclinical mastitis, with prevalence rates of 37.1% and 62.9%, respectively. Out of 1133 quarters examined, 212 (18.7%) were found to be infected, 83 (39.2%) clinically and 129 (60.8%) subclinically. The prevalence of mastitis was significantly higher in Holstein-Friesian than in indigenous Zebu, in non-lactating cows than in lactating cows, in the early lactation stage than in the mid-lactation stage, in cows with lesions and/or tick infestation on skin of udder and/or teats than in cows without this factor, and in the wet season than in the dry season. Mastitis increased with parity number (R = 0.9). Of 248 CMT and clinically positive udder quarter samples analysed microbiologically, 212 were culturally positive for known mastitis pathogens and 36 were negative. Of the 199 positive samples, Staphylococcus accounted for 39.2%, Streptococcus for 23.6%, coliforms for 14.1%, Micrococcus and Bacillus species for 8.0% each and Actinomyces or Arcanobacterium (Corynebacterium) for 7.0%. It was concluded that there was a high prevalence of clinical and subclinical mastitis, mainly caused by Staphylococcus aureus, Streptococcus agalactiae and Escherichia coli, in this study area.     

不同日粮氮水平对山羊氮代谢和微生物蛋白质合成的影响

本试验旨在探讨不同日粮氮水平对内蒙古白绒山羊氮代谢和微生物蛋白质合成(MCP)的影响,以达到提高氮利用率,减少环境污染和饲料资源的浪费。试验选用9只体况良好、体重为(43.83±2.95)kg,装有瘤胃瘘管的内蒙古白绒山羊,按体重随机分为3组,每组3只。日粮分为低氮7.5%、中氮10.5%、高氮13.5%3个氮水平。试验使用常规试验方法分析测定粪尿血液等生化指标,通过全收尿法和尿嘌呤衍生物法估测MCP。结果表明:随着氮水平增加,氨氮(NH3-N)浓度、氮摄入量、尿氮排出、尿中尿素氮(UUN)和MCP显著增加(P0.05),干物质采食量(DMI)显著降低(P0.01);沉积氮占总摄入氮的比例在中氮组最高,MCP在高氮组最高。综上所述,适当降低日粮氮水平可减少粪尿氮排放,提高反刍动物氮利用率。     

Microsporidial keratopathy in two dogs

A microsporidial keratopathy is described in two dogs. Both dogs presented with a unilateral stromal keratopathy characterized by multifocal coalescing opacities, and the diagnosis was made on histopathologic examination of keratectomy specimens. Transmission electron microscopy (TEM) on formalin‐fixed, paraffin‐embedded corneal tissue was performed in one dog, and the morphologic features were consistent with Nosema species infection. Both dogs were initially diagnosed and treated by superficial keratectomy. One dog received additional antifungal medication and underwent a penetrating keratoplasty following local recurrence two years later. No other systemic lesions attributable to the microsporidial infection were identified clinically. The clinical and diagnostic pathology findings, treatment, and follow‐up are discussed.     

优质肉鸡S3系体重与体尺性状指标的主成分分析

为研究地方优质肉鸡S3系体重和体尺性状之间的内在相关性,12周龄时选取同一饲养条件下的150只鸡(公母各半)进行体重和体尺性状等7个指标的测定。结果表明:S3系公鸡的体重、体斜长、龙骨长、胸角均显著高于母鸡(P0.05);公母鸡体重、体斜长、胸宽、胫围这4项指标变异系数较大,有较大选育空间;体重与体斜长、龙骨长、胸宽、胸角、胫围呈极显著正相关(P0.01),相关系数分别为0.57、0.52、0.51、0.49和0.47,与胸深、胫长呈显著相关(P0.05),相关系数分别为0.44和0.39;其他各体尺指标间也存在不同程度的正负相关性(P0.05或P0.01);体重和7个体尺性能指标综合成5个复合指标,累计贡献率达92.6355%,其中第l、2、3、4、5主成分分别解释总变异的36.5353%、22.8642%、13.3115%、10.4535%和8.4710%;各主成分的特征根分布较广,经统计计算入选的5个主成分所包含信息的侧重点各有相同,分别都在一定程度上反映了S3鸡的体型特征和生长发育规律,为今后选育出更加符合市场需求的屠宰加工优质型肉鸡指明了的方向。     

Efficacy of tropicamide,homatropine, cyclopentolate,atropine and hyoscine as mydriatics in Angora goats

Abstract

AIM: To document the efficacy of five commercially available mydriatics for their potential for diagnostic and therapeutic use in Angora goats.

METHODS: Over 8 weeks, the mydriatic effects of 1% tropicamide, 2% homatropine, 1% cyclopentolate, 1% atropine and 0.25% hyoscine were evaluated. Given as block treatments, drugs were applied randomly to one eye of 10 Angora goats, and the contralateral eye served as a control. Vertical and horizontal pupil diameters were measured to document onset ofeffect, time to reach a difference of 5 mm in the vertical/horizontal pupil diameter between eyes, time to maximum pupillary dilation, and duration of mydriatic action.

RESULTS: Onset of mydriasis for all drugs occurred within 15 minutes. Time to reach a difference of 5 mm in the vertical pupil diameter between eyes was shortest for 1% tropicamide and 0.25% hyoscine (0.5 h), then 2% homatropine and 1% atropine (0.75 h), and longest for 1% cyclopentolate (1.5 h). The maximum vertical pupillary dilation occurred earliest with 1% tropicamide and 1% atropine (2 h), followed by 0.25% hyoscine (3 h), 2% homatropine (4 h), and latest with 1% cyclopentolate (8 h). The duration of vertical dilation of the pupil was shortest with 1% tropicamide (6 h), then 2% homatropine (12 h), 1% cyclopentolate (12 h), 1% atropine (24 h), and longest for 0.25% hyoscine (96 h).

The time to reach maximum horizontal dilation of the pupil in treated eyes was shortest with 1% cyclopentolate (1 h), followed by 1% tropicamide (1.5 h), 0.25% hyoscine (3 h), 2% homatropine (3.5 h), and 1% atropine (4 h). The duration of horizontal pupil dilation was shortest with 1% tropicamide (4.5 h), and longest with 0.25% hyoscine (48 h).

CONCLUSION: All five mydriatics induced clinical dilation. Tropicamide (1%) had the shortest duration of effect, but gave incomplete dilation. Good dilation was achieved with 1% cyclopentolate and 2% homatropine, but took too long to reach maximum dilation for routine mydriasis. The largest vertical dilation of the pupil was achieved with 1% atropine and 0.25% hyoscine, but pupils remained dilated for more than 24 h.

CLINICAL RELEVANCE: For routine mydriasis in goats, it is recommended that 1% tropicamide be used, though there may be incomplete dilation. For a longer duration of mydriasis, such as in the treatment of anterior uveitis, 1% atropine or 0.25% hyoscine would be the drugs of choice.