Influence of lidocaine and diazepam on peri-induction intraocular pressures in dogs anesthetized with propofol–atracurium

The purpose of this study was to evaluate the effects on the intraocular pressure (IOP) of lidocaine or diazepam administered intravenously (IV) before induction of anesthesia with propofol-atracurium and orotracheal intubation in normal dogs, as well as the effects on the IOP of lidocaine applied topically to the larynx after induction with propofol-atracurium. We randomly assigned 32 random-source dogs, obtained from municipal pounds, to receive the following: lidocaine, 2 mg/kg IV, with saline, 0.1 mL/kg topically applied to the larynx (LIDOsal); saline, 0.1 mL/kg IV, with lidocaine, 2 mg/kg topically applied to the larynx (SALlido); diazepam (Valium), 0.25 mg/kg IV, with saline, 0.1 mL/kg topically applied to the larynx (VALsal); or saline, 0.1 mL/kg IV, with saline, 0.1 mL/kg topically applied to the larynx (SALsal). We measured arterial pressure directly, by means of an indwelling catheter placed in a peripheral artery. Anesthesia was induced with propofol, 8 mg/kg IV, until loss of jaw tone, followed by atracurium, 0.3 mg/kg IV. We measured the IOP in triplicate in each eye before premedication, before induction, before intubation, and after intubation. After induction, the IOP was significantly increased except in the VALsal group, in which the IOP was significantly lower than in the negative-control group before intubation. After intubation, the IOP was significantly elevated in all the groups compared with the values before induction. Cardiovascular parameters were essentially similar in all the groups, except for a significant increase in blood pressure after intubation in the SALlido group. Thus, propofol-atracurium anesthesia causes an increase in IOP that is blunted by diazepam. However, diazepam does not blunt the increase in IOP observed with intubation.     

日粮中添加植酸酶和锌对断奶仔猪生产性能及其组织锌浓度的影响

通过三个试验测定日粮中植酸酶、过量的锌及两者共同对哺乳仔猪的影响。在所有的试验中,每个处理组有5～7栏,每栏有6～7头猪,当日粮中添加植酸酶时,则日粮中钙和有效磷的水平降低0.1%,锌是通过氧化锌的形式添加,试验日粮中含锌水平均为127mg/kg,本试验的周期为19～21d。在试验1中,试验采用2×3因子试验设计,两个水平的植酸酶(即0和500植酸酶单位/kg)和三水平过量的锌(即0,1000和2000mg/kg)。仔猪(5.7kg和18日龄)被随机分配采食以上日粮。试验表明,平均日增重(ADG)和平均日采食量(ADFI)随日粮中锌含量的增加而线性增加,第一阶段为(P=0.01～0.06),第二阶段为(P=0.02～0.09),整个试验阶段为(P=0.01～0.02),肉料比(G∶F)也随日粮锌含量的增加而线性增加,但仅限于第一阶段(P=0.01)。当仔猪采食1000或2000mg/kg锌时的同时添加植酸酶可降低第二阶段ADG(锌与植酸酶互作;P=0.10),但对整个试验周期内ADFI没有影响(P=0.27～0.62),并可降低第二阶段G∶F(P=0.01),及整个试验周期内G∶F(P=0.07)。随着日粮锌添加量的增加,血浆中锌含量也随之增加(Zn2,P=0.01),并且不受植酸酶添加的影响(P=0.70)。在试验2中,试验采用2×2因子试验设计,两个水平的植酸酶(即0和500植酸酶单位/kg)和两水平过量的锌(即0和2000mg/kg)。仔猪(5.2kg和18日龄)被随机分配采食以上日粮。试验表明,日粮中锌含量的增加可使第二阶段ADG和肉料比增加(P=0.02～0.09)和整个试验阶段的ADG和G∶F增加(P=0.07～0.08),但对第一阶段ADG和整个试验阶段ADFI的变化没有影响。植酸酶的添加可增加第二阶段ADG(P=0.06)和G∶F(P=0.01)。当仔猪采食2000mg/kgZn和植酸酶时,G∶F值最大(锌与植酸酶互作;P=0.01)。骨(20日龄)中锌和血浆锌(7和20日龄)随着日粮中锌的添加量的增加而增加(P=0.01),但不受植酸酶添加的影响(P=0.51～0.90)。在试验3中,仔猪(5.7kg和19日龄)被随机分配采食添加500植酸酶单位/kg的植酸酶或不添加植酸酶的基础日粮或添加500植酸酶单位/kg的植酸酶或不添加植酸酶且钙和有效磷含量降低0.10%的基础日粮。试验表明,植酸酶的添加对仔猪生产性能没有影响(P=0.21～0.81)。降低钙和有效磷的含量,可降低整个试验周期内ADG,ADFI和G∶F(P=0.02～0.08)。这些试验结果表明,日粮中添加过量的锌可增加ADG及血浆和骨中锌的浓度。日粮中植酸酶对血浆和骨中锌的浓度没有影响。     

多糖和寡糖的体外发酵特性及其对鸡盲肠微生物菌群的影响

本研究采用体外累积发酵产气法和16SrDNA指纹图谱鉴定技术研究了来自香菇、银耳和黄芪的天然免疫活性多糖(LenE,TreE和AstE)及酵母胞壁甘露寡糖(MOS)对鸡肠道微生物菌群及其发酵特性的影响。结果表明,三种多糖提取物的总糖含量均占干物质的60%以上,而MOS总糖含量在90%以上。多糖和寡糖具有不同的发酵模式;MOS、AstE和LenE三种糖的发酵模式相似,呈一阶段发酵模式;TreE呈两阶段的发酵模式。三种糖中,MOS和AstE发酵速度较TreE快。MOS和AstE在发酵后总VFA产量最高,pH最低;黄芪多糖发酵后产生较多的直链脂肪酸和较低的氨。这些多糖和寡糖提取物影响肠道微生物的活性和组成成分,体现在发酵模式和发酵终产物的显著改变上。以上研究结果表明,来自香菇、银耳和黄芪的天然免疫活性多糖(LenE,TreE和AstE)及酵母胞壁甘露寡糖(MOS)在体外发酵后,均具有显著改变鸡盲肠微生物发酵终产物的含量和盲肠微生物活性的作用。     

Association of brook trout and Oncorhynchus spp. with large wood jams in a Lake Superior tributary in a northern old‐growth watershed

Wood in streams functions as fish habitat, but relationships between fish abundance (or size) and large wood in streams are not consistent. One possible reason for variable relationships between fish and wood in streams is that the association of fish with wood habitat may depend on ecological context such as large‐scale geomorphology. We studied the relationship between salmonid assemblages and large wood jams (LWJ) in four settings that differed geomorphically at the scale of the stream corridor along a tributary to Lake Superior in old‐growth conifer–hardwood forest in northern Michigan. The focal fish species of this study were brook trout (Salvelinus fontinalis), which were wild in the stream. Relocation efforts for coaster brook trout (an adfluvial life history variant of brook trout) were ongoing in the study stream. We measured fish abundance and length in pairs of pools of similar size and substrate, but varying in the presence of LWJ; this allowed us to evaluate associations of fish simply with the presence of LWJ rather than with other channel or flow‐shaping functions of LWJ. The length of Oncorhynchus spp. and young introduced brook trout was not strongly correlated with LWJ presence; however, the presence of LWJ in pools was positively correlated with larger wild brook trout. We also found that the correspondence of LWJ with the abundance of salmonids appears to be moderated by the presence of alternative habitat in this relatively natural, old‐growth forest stream.     

The role of antibody in protection against African swine fever virus

Intraperitoneal immunization of pigs with anti-African swine fever virus (ASFV) antibody protected them against the effects of challenge with ASFV. This protection, which was exemplified by a reduction in pyrexia and viraemia plus an increased survival time, appeared to be mediated through the effects of complement-dependent antibody-mediated cytotoxicity (CDAC) or antibody dependent cell mediated cytotoxicity (ADCC). Experiments suggested that the reduction in viraemia was associated with complement lysis whereas protection was conferred by ADCC.     

Fine-scale vegetation patches decline in size and cover with increasing rainfall in Australian savannas

Fine-scale vegetation patches (<5 m in width) are critically important in many landscapes because they function to obstruct surface flows of water and wind. These obstructions increase the infiltration of runoff and the capture of nutrients in runoff sediments and in wind-blown soil and litter. The importance of redistribution of runoff into runon patches from spaces between patches (fetches) is likely to be greater in drier than in wetter environments. In this paper we examine the hypothesis that the ratio of fetch to patch decreases as rainfall increases, and that this trend will be most evident on intermediate-textured soils because these soils are more prone to runoff. We measured fine-scale patches on 38 sites with sand, loam or clay soils. Sites were located along a 1000-mm rainfall gradient in the savannas of northern Australia. The width and intercept length of patches and the fetch between patches was measuring along line transects of 100–120 m oriented down slope. We found that the ratio of fetch to patch area did not decrease with decreasing rainfall, but increased on both sand and loam soils. This result was because with increasing rainfall mean spacing between patches disproportionally increased while mean patch size and cover declined. The cover of patches was negatively correlated with tree canopy cover, which significantly increased with rainfall. This negative correlation suggests that in higher rainfall savannas the size and spacing of ground-layer patches is controlled by the tree layer, and that as rainfall decreases this control decreases and runoff-runon processes increasingly structure the landscape. For savannas on clay soils these trends were not significant except that on the highest rainfall sites the cover of ground-layer patches was nearly 100% while trees were absent.     

Gastric emptying of liquids in the dog: serial test meal and modified emptying-time techniques

A serial test meal technique was used in the dog to evaluate the gastric emptying of a liquid test meal. On separate days, a phenol red test meal was placed in the stomach and completely aspirated at different times. A composite representation of the gastric emptying pattern was obtained for each dog, and a set of normative data was generated. Three emptying determinants (emptying time, half-life, and starting index) were calculated. The basic pattern of canine gastric emptying was linear and declined exponentially or as a function of the square root of the gastric volume. A modified emptying-time technique (METT) correlated well with the serial test meal and a set of normative values was determined. The METT was performed by aspirating test meal from the stomach 30 minutes after instillation. The METT was a simple and inexpensive technique that could be performed in 1 short testing period. With the METT, the half-life of gastric emptying was calculated, using the log of the percentage of retention of test meal; gastric emptying time was calculated, using the square root of the percentage of retention of test meal. Acetylpromazine was shown not to alter gastric emptying of a liquid test meal.     

Extraocular myositis in the dog.

Extraocular myositis is a rare condition in the dog and is poorly reported in the peer-reviewed veterinary literature. This case series and review are designed to be of value to those veterinary ophthalmologists seeking to investigate the disease further and also to veterinarians outside the specialty, for whom this may be their first introduction to the disease.