The use of vascular access ports in nonanesthetized green iguanas (iguana iguana) to collect baseline arterial blood gas parameters.

The green iguana, Iguana iguana, is used as a model in reptile anesthesia research because of its size, availability, and the body of knowledge characterizing its physiology. Arterial blood gas values in nonanesthetized green iguanas have not been determined because of the technical difficulty involved. Vascular access port (VAP) placement to facilitate blood sampling has been described in other species, but not lacertilians. This abstract describes the technique for placement of VAPs and the values for arterial blood gas parameters in seven 1 kg adult green iguanas. Using sterile technique, a 1.5 cm incision was made on the lateral side of the neck. Blunt dissection ventral to the external jugular vein revealed the internal and external carotid arteries near their bifurcation. The catheter was inserted into the internal carotid artery and then guided to the common carotid artery. The other end of the catheter was tunneled below the skin to a subcutaneous location, caudal‐dorsal to the iSPSilateral scapula. The skin was closed and the port was flushed twice a week with heparinized saline. Post‐operatively, the VAPs were well tolerated by the iguanas. Difficulties included port disconnection (n = 1), inability to aspirate blood after a few weeks (n = 2), and infection (n = 1). The iguanas were breathing room air prior to and during blood collection. From the five functional VAPs, the blood pH, PCO₂, PO₂, HCO^‐₃, and BE (measured at 37 °C) were 7.45 ± 0.06; 37.5 ± 7.0 mm Hg, 99.0 ±16.6 mm Hg, 25.4 ± 2.5 mmol L^–1, and 1.5 ±2.4 mmol L^–1 respectively (mean ± SD). VAPs can be successfully used to facilitate collection of arterial blood gas samples in green iguanas. These values are similar to those reported for most mammalian species. This technique should facilitate research in anesthesiology and respiratory physiology of iguanas and other lacertilians.     

An information system for the control of Puccinia hordei: I—Design and operation

The design and operation of a farm-level computer-based management information system for advising farmers about the use of fungicide for the control of brown rust of barley are described. Once the disease has been observed in the field, epidemics are projected forward using simulation components to model key weather variables and the resultant progress of the rust. The strategies open to a farmer midway through the growing season are assessed using the criteria of expected monetary value and expected utility. The results of preliminary validation work are presented, and the usefulness of the information system is discussed.     

ANIMAL PREFERENCE IN RELATION TO THE CHEMICAL COMPOSITION AND DIGESTIBILITY OF VARIETIES OF COCKSFOOT

Assessments of animal preference (measured as mean % herbage removed) were made on varieties of cocksfoot in Yorkshire and in Scotland, and parallel chemical analyses were carried out. A similar range of varieties were examined at progressive stages of spring growth at Cambridge. In vitro digestibility tests were made also. In the Yorkshire trials, a significant positive relationship was established between soluble carbohydrates and animal preference and a negative correlation between fibre and animal preference. In Scotland, the relationship between soluble carbohydrate and animal preference was less pronounced. Animal preference in the spring was for the early varieties which have thick and succulent stems up to the stage of ear emergence. In the aftermath animal preferences were less marked.
In trials at Cambridge, the early varieties, notably Scotia, were higher than the late varieties both in digestibility and in soluble carbohydrates. This tendency was also present in Scotland but was less pronounced.     

Extraction of light filth from unground marjoram: collaborative study

The present method for filth in underground marjoram is conducted in 2 parts. The first of these, which is for heavy filth and sand, requires the spice to be boiled with petroleum ether, then floated off with chloroform and, if needed, carbon tetrachloride. The second part, which is for light filth, is dependent on completion of the heavy filth section. After the spice is air-dried, the light filth is extracted with heptane and water. The proposed method was developed to make light filth independent of heavy filth analysis, improve filth recoveries, and reduce microscopic examination time. The light filth is extracted by ethanol defatting followed by a combination 15-60% ethanol/mineral oil extraction in a Wildman trap flask. Tween 80-NaEDTA solution is added to the trapping system to reduce the rising of excess plant material to the trap interface. The official method (AOAC 13th edition secs 44.142, 44.120(b)) produced an average of 8 extraction papers per test portion and microscopic examination took an average of 88 min per test portion. The official method gave average recoveries of 14% for rodent hairs and 26% for insect fragments with 2 spike levels of 15 and 30 for each filth element. Recoveries of the 2 levels of each spike were not significantly different (P greater than 0.05). The proposed method gave average recoveries of 73% for rodent hairs and 70% for insect fragments. The proposed method has been adopted official first action to replace AOAC 13th edition secs 44.142 and 44.120(b) for unground marjoram only.     

Facial eczema management protocols used on dairy farms in the North Island of New Zealand and associated concentrations of zinc in serum

AIMS: To describe and evaluate the current practices used to manage and prevent facial eczema (FE) in North Island dairy herds, and determine the within-herd prevalence of cows with elevated activities of gamma glutamyl transferase (GGT), and with concentrations of Zn in serum <18?μmol/L.

METHODS: Between January and May 2014, 105 herd managers from throughout the North Island of New Zealand were invited to participate in the study when regional spore counts for Pithomyces chartarum started to rise towards 30,000 spores/g pasture. Managers selected 10 representative cattle that were weighed and blood-sampled by the herd veterinarian. Blood samples were analysed for concentrations of Zn in serum and GGT activity. Pasture samples were also collected and submitted for spore count estimation. Finally a survey of farm management practices relating to prevention of FE was completed by the herd manager. A mixed-effects logistic regression model was used to determine associations between herd-level and cow-level explanatory variables and the probability of a cow having a concentration of Zn in serum <18?µmol/L.

RESULTS: Of the 1,071 cows tested, 79 (7.3 (95% CI=5.8–9.0)%) had GGT activity in serum >300?IU/L, and 35/106 (33 (95% CI=24.2–42.8)%) herds had ≥1 of the 10 cows sampled with GGT activity >300?IU/L. Of the 911 cows that were being treated with Zn, concentrations of Zn were between 18–35?μmol/L in 398 (43.6 (95% CI=40.4–46.9)%) cows, were >35?μmol/L in 32 (3.5 (95% CI=2.4–4.1)%) cows, and <18?μmol/L in 479 (52.6 (95% CI=49.3–55.9)%) cows. After adjusting for the confounding effect of region, the odds of a cow having concentrations of Zn in serum <18?μmol/L were 5.5 (95% CI=1.1–29) times greater for cows supplemented with zinc in water compared with those supplemented by drenching. Of the 105 herd managers, 103 (98%) stated that they had access to regional spore count data, but only 35/105 (33%) reported that they measured spore counts on their own farm. Overall, 98/105 (93%) managers reported that they had some form of FE management programme in place. Fungicides were used on their own or in combination with zinc treatments in 10 herds, ZnSO₄ in water troughs was used in 68 herds, oral drenching with ZnO in nine herds, and ZnO supplied in-feed in 26 herds. Estimated daily dose rates of zinc were less than that required to treat a 400?kg cow on 42/68 farms that administered ZnSO₄ in the water or ZnO as a drench.

CONCLUSION AND CLINICAL RELEVANCE: This study has shown that FE management on dairy farms in the North Island of New Zealand could be substantially improved. It is likely that improved FE management would occur if herd managers were provided with more feedback on the success (or otherwise) of their FE management programmes.     

The influence of lime and nitrogen fertilisers on spore counts of Pithomyces chartarum in pasture

AIMS: To determine whether the application of lime or nitrogen to pasture affected the spore counts of Pithomyces chartarum.

MATERIALS AND METHODS: The lime application studies were undertaken on a spring-calving, pasture-based, commercial dairy farm near Te Awamutu, New Zealand. On 6 November 2012, five randomly selected paddocks were split into three equal sections. In two of the sections, lime was applied at either 1.5 or 2.5?t/ha, and the central section was left as an untreated control. Each section was sampled for spore counting weekly from 16 January to 15 May 2013.

Starting in January 2013, five other randomly selected paddocks were monitored for spore counts. On 20 March 2013 the average spore counts in three paddocks were >100,000 spores/g of pasture. These paddocks were then divided into three equal sections and lime was applied as described above. Spore counting in each section continued weekly until 15 May 2013.

The nitrogen application study was carried out on three commercial dairy farms near Te Awamutu, New Zealand. Two randomly selected paddocks on each farm were divided into three equal sections and, on 20 December 2012, nitrogen in the form of urea was applied at either 50 or 80?kg urea/ha to two of the sections; the central section remained as an untreated control. Each section was sampled for spore counting weekly from 16 January to 15 May 2013.

RESULTS: Following pre-summer lime application, treatment at 1.5 or 2.5?t/ha did not affect spore counts over time compared with the control section (p>0.26). Similarly following autumn lime application, treatment at 1.5 or 2.5?t/ha did not affect spore counts over time compared with the control section (p>0.11). Following nitrogen application median spore counts remained <20,000 spores/g pasture throughout the trial period and there was no effect of treatment on spore counts over time (p>0.49).

CONCLUSION: This study found that application of lime before the risk period for facial eczema, in November, application of lime after a spore count rise, in March, or urea application in December did not affect changes in number of spores produced by P. chartarum.

CLINICAL RELEVANCE: This study does not support previous suggestions that fertilising pasture with lime or urea could alter the spore counts of P. chartarum. Fertiliser use does not provide an alternative to, or support, conventional methods of facial eczema control such as zinc prophylaxis or treatment of pasture with fungicides.     

加快石漠化地区草地植被恢复促进喀斯特地区生态环境建设

石漠化问题加剧了喀斯特地区的水土流失和旱涝等自然灾害,进一步加深了该地区贫困程度,越来越成为制约社会、经济和生态全面发展的桎梏.恢复喀斯特地区草地植被是解决喀斯特地区石漠化问题的根本出路和保护生态环境的最后屏障,可以在快速有效地减少水土流失的同时短期内大幅度增加农民收入,实现可持续发展.恢复石漠化地区草地植被,要在保护和合理利用现有草地资源的基础上, 与种植优质牧草、发展草地畜牧业相结合, 与推广沼气技术相结合, 与生态旅游相结合.要拓宽投融资渠道, 增加资金投入.