Long Chain Fatty Acids of Diet as Factors Influencing Reproduction in Cattle

Cattle are fed moderate amounts of long chain fatty acids (FA) with the objective to enhance lactation and growth; however, recent interest on lipid feeding to cows has focused on reproduction, immunity and health. Increasing the caloric density of the ration by fat feeding has generally improved measures of cow reproduction, but when milk yield and body weight losses were increased by fat supplementation, positive effects on reproduction were not always observed. Feeding fat has influenced reproduction by altering the size of the dominant follicle, hastening the interval to first postpartum ovulation in beef cows, increasing progesterone concentrations during the luteal phase of the oestrous cycle, modulating uterine prostaglandin (PG) synthesis, and improving oocyte and embryo quality and developmental competence. Some of these effects were altered by the type of FA fed. The polyunsaturated FA of the n-6 and n-3 families seem to have the most remarkable effects on reproductive responses of cattle, but it is not completely clear whether these effects are mediated only by them or by other potential intermediates produced during rumen biohydrogenation. Generally, feeding fat sources rich in n-6 FA during late gestation and early lactation enhanced follicle growth, uterine PG secretion, embryo quality and pregnancy in cows. Similarly, feeding n-3 FA during lactation suppressed uterine PG release, and improved embryo quality and maintenance of pregnancy. Future research ought to focus on methods to improve the delivery of specific FA and adequately powered studies should be designed to critically evaluate their effects on establishment and maintenance of pregnancy in cattle.     

Recurrent somatic embryogenesis and plant regeneration in Coriandrum sativum L.

An efficient method of repetitive somatic embryogenesis and plant regeneration was established in Coriandrum sativum L. Embryogenic callus was induced from cotyledon and hypocotyl segments on Murashige and Skoog (MS) medium with 4.52 μM 2,4-dichlorophenoxy acetic acid (2,4-D), upon subculturing on medium having same level of 2,4-D at an interval of 3 weeks developed somatic embryos, which progressed to cotyledonary stage through early developmental stages of somatic embryogenesis. The transfer of somatic embryos at an early cotyledonary and cotyledonary stage in clumps in succession to fresh 4.52 μM 2,4-D supplemented medium developed embryos in a cyclic manner. Upon transferal to embryogenic clumps (cotyledonary embryos) to modified MS medium (4 g l⁻¹ KNO₃, 0.29 g l⁻¹ NH₄NO₃, 3 mg l⁻¹ thiamine HCl, 0.5 mg l⁻¹ pyridoxine HCl, and 5 mg l⁻¹ nicotinic acid), the embryos irrespective of the cycles underwent maturation and germination. Germinating embryos transferred to half-strength MS medium favored healthy growth of plantlets. The system of recurrent somatic embryogenesis in coriander offers a system for genes transfer and also scale-up production of modified plants.     

Assessment of survey radiography as a method of diagnosing bilateral laryngeal paralysis in dogs

The gold standard for diagnosis of laryngeal paralysis is laryngoscopy under light anesthesia. This prospective analytical cross-sectional study aimed to determine whether a radiographic assessment of the larynx could be used as a non-invasive screening tool for diagnosing laryngeal paralysis in non-sedated animals, as the laryngeal ventricles may appear wider in affected animals. The laryngeal ventricles of 18 dogs with bilateral laryngeal paralysis composing the affected group and 25 non-sedated dogs presenting no respiratory abnormality composing the control group were evaluated using right lateral radiography of the larynx. Three observers measured the ratios of the maximal ventricular length and surface to the body length of the third cervical vertebra (MVL/LC3 and VS/LC3, respectively). They also subjectively assessed the ventricular shape as either normal or rounded. The most accurate criterion was found to be MVL/LC3, as the respective areas under the ROC curves were 0.96 (95% confidence interval [CI]: 0.95–0.97), 0.89 (95% CI: 0.87–0.91), 0.80 (95% CI: 0.65–0.95) for MVL/LC3, VS/LC3, and ventricular shape evaluation, respectively. Based on ROC curve analysis, two thresholds of clinical interest were set for the MVL/LC3; bilateral laryngeal paralysis was very unlikely for values < 0.3 and very likely for values > 0.5. The findings of this study support the use of lateral laryngeal radiography as a screening tool for diagnosing bilateral laryngeal paralysis. However, further diagnostic tests remain required if MVL/LC3 lies between these threshold values or if clinically indicated. Further studies are warranted to explore the use of laryngeal radiography in unilateral paralysis and other laryngeal or oropharyngeal diseases.     

Dead wood in European beech (Fagus sylvatica) forest reserves

Data were analysed on the volume of dead wood in 86 beech forest reserves, covering most of the range of European beech forests. The mean volume was 130 m³/ha and the variation among reserves was high, ranging from almost nil to 550 m³/ha. The volume depended significantly on forest type, age since reserve establishment and volume of living wood. More dead wood was found in montane (rather than lowland/submontane) reserves, longer-established reserves (time since designation) and reserves with higher volumes of living wood.

On average, fallen dead wood contributed more to the total dead wood volume than standing dead wood. The percentage of dead wood that was standing was almost twice as high in montane than in lowland/submontane forest reserves (45% versus 25%). The volume of dead wood at selected sites changed considerably over time. The fluctuations were significantly higher in lowland/submontane than montane reserves, possibly connected with differences in the disturbance regimes and especially damage caused by windstorms. In NW Europe, the blow down of formerly managed, even-aged stands led to extraordinary high volumes of dead wood shortly after reserve establishment.

The implications for forest management and biodiversity conservation are discussed. An increase in dead wood volumes must be carried out in accordance with the local/regional forest type and disturbance regime. Thus, in order to fulfil the requirements of as many wood-depending organisms as possible, it is important to preserve not only larger amounts of dead wood, but also dead wood of different types and dimensions as well as securing a long-term continuity of dead wood.     

Hematologic changes associated with half-body irradiation in dogs with lymphoma

BACKGROUND: Reports describe the technique and efficacy of half-body irradiation (HBI) of dogs with lymphoma, but few describe the distinctive toxicoses associated with the combination of HBI and chemotherapy. HYPOTHESIS: HBI would transiently affect myelocytic and erythroid variables as assessed by serial analysis of complete blood counts. ANIMALS: Twenty-nine dogs with lymphoma treated with HBI during 2002 and 2003. METHODS: A retrospective study of medical records of 29 dogs was performed. Two HBI protocols were used, resulting in delivery of either 6 Gy or 8 Gy to each half of the body, 1 month apart. Dogs received chemotherapy before, during, or after irradiation, or at multiple times. Serial hematology was available for all dogs. Data were analyzed between collection periods by analysis of variance (ANOVA) RESULTS: The mean granulocyte count significantly (P < .01) decreased from 10,017 cells/microL (data range 3,001-20,170 cells/ microL) before the first radiation treatment to 3,250 cells/microL (820-4,400 cells/microL) at week 5 (P < .01). Three weeks after this nadir, the mean increased to 10,150 cells/microL (900-26,700 cells/microL). The hematocrit did not change (36-38%). Thrombocytopenia (<100,000/microL) occurred in 10 dogs. Two dogs died because of complications associated with thrombocytopenia. No significant difference in toxicity was found between the 6 Gy and 8 Gy group. CONCLUSIONS AND CLINICAL IMPORTANCE: HBI was myelosuppressive but effects were short term and resolved in 22 of 24 dogs. Further studies are needed to elucidate the safety and role of HBI in the treatment of dogs with lymphoma.     

Breeding cassava for resistance to cassava mosaic disease

Summary Cassava mosaic disease (CMD) is one of the most serious and widespread diseases throughout cassava growing areas in Africa, causing yield reductions of up to 90%. Early research on breeding of cassava (Manihot esculenta Crantz) for resistance to CMD in Africa is reviewed. Changes in population size and in activity of the white-fly vector to CMD (Bemisia tabaci Genn.) in relation to changes in environmental conditions such as amount and distribution of rainfall, light intensity and temperature are discussed in relation to screening for resistance to CMD. Over the past eight years, significant progress has been made at the International Institute of Tropical Agriculture (IITA). Resistance to CMD has been successfully incorporated into high yielding cultivars of acceptable quality. The CMD resistant material has been evaluated and many promising clones have been selected in various countries in tropical Africa and India. The resistance has been effective in those countries.     

Unusual metastatic behavior and clinicopathologic findings in eight cats with cutaneous or visceral hemangiosarcoma

Eight cats with visceral or cutaneous hemangiosarcoma were evaluated, and unusual metastatic and clinicopathologic behavior was evident in each. Cutaneous hemangiosarcoma is generally believed to be locally aggressive and slow to metastasize. These 8 cats with cutaneous hemangiosarcoma, however, developed metastatic disease after initial surgical resection; only 1 had local regrowth of the tumor. All cats with visceral hemangiosarcoma had metastasis at the time of diagnosis, which is consistent with cats of other reports. Three of 8 cats had evidence of disseminated intravascular coagulation, including increased prothrombin time and partial thromboplastin time, decreased number of platelets, and anemia. These potential complications need to be considered when planning diagnostic and treatment protocols.     

Dynamic responses of cattle to thermal heat loads

The focal point of this limited review is bioenergetic research conducted in the Biological Engineering Research Unit at the U.S. Meat Animal Research Center (MARC), using recently developed instrumentation and analytical techniques. The dynamics of observed thermoregulatory responses in cattle to thermal heat load challenges are explored, with an emphasis on physiological and behavioral parameters of body temperature, respiration rate, and feed intake. Observations of body temperature, especially tympanic temperature, have shown hot environments to cause phase shifts, increased amplitude, and increased means for diurnal rhythms. Fractal analysis of body temperature records obtained at 2- to 10-min intervals has been found to be robust for objectively differentiating among responses of cattle in cool to hot environments, and it indicates a stress threshold of approximately 25 degrees C (coincident with declining feed intake). Other analyses determined a 21 degrees C threshold for increased respiration rate. The reported observations and analyses provide further understanding of how and why the animals respond to environmental challenges, an understanding that is necessary for refining performance models and developing energetic and thermoregulatory models. The dynamic responses are discussed in the context of establishing criteria for proactive environmental management for cattle during hot weather, using heat waves as an example.     

Phytomedicine in dogs and cats: web-based survey among veterinarians in Austria, Germany and Switzerland

In the last decades phytopharmaceuticals have stabilized their significance in human medicine. The aim of this study was to obtain information about the present situation of phytomedicine in three German-speaking countries. For that purpose questionnaires were sent via internet to 2675 veterinarians in Austria, Germany and Switzerland and the collected 189 answers were statistically evaluated. As shown in this paper, there is an increasing interest in veterinary phytotherapy. Presently three-quarters of the veterinarians are using phytoproducts in clinical practice. Herbal medicinal products are only seldom used in eye and ear infections as well as in endo- and ectoparasitoses but more often in diseases of the liver, joints, kidneys, heart and skin. Generally, phytodrugs are more frequently applied in chronic diseases as well as secondary medication, whereas the time of treatment usually exceeds one month. Basic advantages of medicinal phytoproducts have been shown to be the low side effects and the acceptance of the pet-owners and the only disadventage has been reported to be the lack of information. This study clearly shows the upward trend in using herbal drugs by veterinarians but the results also point to the lack of scientific knowledge about phytotherapeuticals in animal health.