1,720,998 research outputs found
Twenty-four-hour rhythm patterns of plasma melatonin in short-day and long-day breeders maintained under natural environmental conditions
Full text linkPhotoperiodic treatments have been of practical interest in controlling seasonal reproduction in sheep, goats and horses. Melatonin is the principal mediator of the environmental photoperiodic message. To investigate the intra- and inter-subject variability of melatonin 24 h rhythm, ten female Italian Saddle horses (8–10 yrs old, mean body weight 525 ± 30 kg), ten female Sarda breed sheep (2–3 yrs old, mean body weight 40.5 ± 2.8 kg) and ten female Sarda breed goats (3–4 yrs old, mean body weight 38.9 ± 4.1 kg), housed individually in a 4 × 4 m soundproof box equipped with 50 × 100 cm opening windows, were subjected to a natural photoperiod of the vernal equinox (sunrise 06:00 h; sunset 18:00 h). Blood samples were collected from each animal, every 3 h over a 48 h period starting at 00:00 h of day 1 and ending at 00:00 h of day 3. Plasma melatonin concentrations were determined by direct radioimmunoassay (MelatoninDirect RIA, Labor Diagnostika Nord GmbH, Nordhorn, Germany). The application of single cosinor method substantiated a circadian rhythm of melatonin with a nocturnal peak in all studied species. The application of two-way ANOVA on the rhythmic parameters indicated statistically significant differences between the three species in all of the cosinor analysis-derived parameters of MESOR, amplitude, acrophase and robustness of rhythm. Analyses of intra- and inter-subject variability indicate that organization of the melatonin 24 h rhythm is characterized by great accuracy of control within and between the individuals of a breed. In conclusion, features of the 24 h rhythm of melatonin among species; however, the 24 h rhythmicity of melatonin each species showed high stability within the various subjects and within the same subject. These findings must be taken into consideration when applying photoperiod and melatonin treatments for breeding purposes
Daily variations of serum lipids in Ovis aries under different lighting and feeding conditions
No full textThe aim of this study was to discriminate the impact of lighting and feeding conditions on the regulation of lipid metabolism in Ovis aries. Six clinically healthy female Comisana ewes, not pregnant and not lactating were kept under different environmental conditions: 12:12 light-dark (LD) cycle, constant darkness and fasting. Blood samples were collected at the end of each period of treatment every 4 h for a 24-h period. Blood concentration of triglycerides, total cholesterol and non-esterified fatty acid showed robust daily rhythmicity in ewes maintained under 12:12 LD cycle and fed ad libitum. Conversely, either constant darkness or fasting had a deep impact on all lipid parameters investigated. Our results suggest that lighting and feeding conditions have an impact on daily variations in lipid metabolism in ewes
Seasonal variations in daily rhythms of activity in athletic horses
No full textCircadian rhythms reflect extensive programming of biological activity that meets and exploits the challenges and opportunities offered by the periodic nature of the environment. In the present investigation, we recorded total activity of athletic horses kept at 4 different time of the year (vernal equinox, summer solstice, autumn equinox and winter solstice), to evaluate
the presence of seasonal variations of daily activity rhythms. Athletic Thoroughbred horses were kept in individual box with paddock. Digitally integrated measure of total activity of each mare was continuously recorded by actigraphy-based data loggers. Horse total activities
were not evenly distributed over the day, but they were mainly diurnal during the year. Daily activity rhythms showed clear seasonal variations, with the highest daily amount of activity during the vernal equinox and the lowest during the winter solstice. Interestingly, the amount of activity during either photophase or scotophase changed significantly throughout the year. Circadian analysis of horse activities showed that the acrophase, the estimated time at which the peak of the rhythm occurs, did not change during the year; it always occurred in the middle of photoperiod.
Analysing the time structure of long-term and continuously measured activity and feeding could be a useful method to critically evaluate athletic horse management systems in which spontaneous locomotor activity and feeding are severely limited. Circadian rhythms are present in several elements of sensory motor and psychomotor functions and these would be
take in consideration to plan training schedules and competitions in athletic horses
Modification of some haematological and haematochemical parameters in horse during long distance rides.
No full textThe aim of this study was to evaluated the effect of the low-intensity long-lasting trial on some haematological and haematochemical parameters during an international endurance race. Six clinically healthy and regularly trained Sella Italiana mares were used. On blood sample collected at rest, at 30 km, and 30’ after the trial, haematological (Red Blood Cell, Haemoglobin, Haematocrit; Mean Corpuscolar Volume, Mean Corpuscolar Hemoglobin, Mean Corpuscolar Hemoglobin Concentration, White Blood Cell and Platelets), and haematochemical parameters (Glucose, Aspartate aminotransferase, Total protein and protein fraction (albumin, α1-globulins, α2-globulins, β-globulins and γ-globulins), Triglycerydes, Cholesterol, Creatinine, Urea, Potassium, Sodium and Chloride) were assessed. One way repeated ANOVA showed a statistical significant effect of low-intensity long-lasting trials on the following parameters: Red Blood Cell (p≤0.009), Haematocrit (p≤0.031), Mean Corpuscolar Hemoglobin Concentration (p≤0.013), White Blood Cell (p<0.0001), Platelets (p<0.0001), α1-globulins (p≤0.038) and γ-globulins (p≤0.009), Creatinine (p≤0.023) and Potassium (p≤0.012). Our results confirm the effects of endurance trial on horse metabolism, underlining that haematological and haematochemical profiles could be an useful index for the prevention of many typical diseases of the athlete horse other than in the assessment of the fitness of the endurance horse
Daily rhythmicity of circulating melatonin is not endogenously generated in the horse
No full textMelatonin secretion exhibits daily rhythmicity in many vertebrate species. In mammals, the rhythmicity is believed to result from two related processes: inhibition of pineal activity by environmental light during the day and stimulation of pineal activity by the master circadian clock at night. While circadian modulation of melatonin secretion under constant environmental conditions has been documented in numerous mammalian species, no extensive survey has been conducted. In this study, we investigated daily/circadian rhythmicity of plasma melatonin concentration, as well as of body temperature and of plasma sodium concentration, in horses maintained under a light-dark cycle and in extended darkness. All three variables exhibited robust 24-h rhythmicity under the light- dark cycle. Whereas rhythmicity of body temperature and sodium concentration persisted in extended darkness, rhythmicity of melatonin concentration did not. These findings strongly suggest that melatonin secretion in the horse is not under circadian control and is modulated only by environmental light
A comparison of daily total locomotor activity between the lactation and the dry period in dairy cattle
No full textThe objective of this study was to investigate the influence of farming management on the total locomo- tor activity (TLA) behaviour in dairy cattle. We recorded 24 h/day TLA in five not pregnant Holstein Frie- sian cows during parts of the lactation and dry periods, by means of an activity monitoring system (Actiwatch miniÒ) for seven days in each period. During mild lactation (period 1) animals were milked and fed twice a day. During the dry (period 2) they were kept to graze all day. In both periods hay and water were available ad libitum. Differences between the photophase and the scotophase were evaluated with a Student t-test. One-way repeated measure ANOVA was used to determine a statistical significant effect of time. A trigonometric statistical model was used to describe the main rhythmic parameters: mean level, amplitude, acrophase and robustness of rhythm.
Our results showed a circadian rhythm of daily TLA in both periods, with different percentages of robustness, and acrophase in the middle of the photophase. The different patterns of activity in the two periods were attributed to the management practise during milking period. These results could be taken in consideration during farming management for the evaluation of such systems used in livestock, with respect to production and welfare
The willingness to pay of Sicilian consumers for a wine obtained with sustainable production method: An estimate through an ordered probit sample-selection model
Full text linkThe growing presence of Sicilian sustainable wine has pushed the research group to investigate and analyse the consumers' behaviour and their potential willingness to pay a premium price for the wine obtained through sustainable production processes. The analysis of the consumer's behaviour towards the wine made with sustainable production methods is carried out in order to provide potentially useful indications to Italian and in particular Sicilian wine enterprises regarding the production and marketing strategies to undertake in a future perspective. This study shows the result of an empirical investigation on the consumption of sustainable wine in Sicily. Through the Ordered (demographic profile, preference and attitudes), which influence the consumers' choices regarding sustainable wine. The assessment, based on the submission of a questionnaire, has highlighted the willingness to pay a premium price on the part of the 546 consumers interviewed. The study points out that the knowledge of sustainable production methods significantly influences the decision to support a premium price for wine consumption. This attests to the fact that a more attentive and informed consumer is ready to pay more for products obtained according to the principles of environmental sustainability
Anaplasma Phagocytophilum Intragranulocytic Morulae in Aborting Sheep: A Herd Case in Sicily
No full textThe present report describes the haematological and serological findings observed in a dairy sheep farm during an aborting outbreak. Fifty ewes divided into two groups were included in the study: group A consisted of 35 healthy ewes and group B consisted of 15 ill subjects. From each ewe, blood samples were collected for microscopic examination and serological assay. After 3 months, all ewes were subjected to microscopic examination, serological and biochemical assay. Morula-containing granulocytes characteristic of A. phagocy- tophilum was observed in all animals of group B. Antibodies against A. phagocy- tophilum were observed in only one animal of group A. Seroconversion was observed after 3 months in five ewes of group A and all animals of group B. Only one subject with negative serology was positive to PCR. Our results con- firm the endemicity of sheep tick-borne fever (TBF) in Sicily and the problem to breeding in an endemic area. We suggest that is necessary to combine the different assays depending on the stage of infection for a correct diagnosis in endemic areas. Periodic evaluation of seroconversion could be helpful to evaluate the progression of TBF in a flock
Clotting profiles in newborn Maltese kids during the first week of life
No full textThe neonatal period is probably the only time when a higher incidence of spontaneous
thromboembolic complications may occur in the otherwise normal, healthy individual. This study was
designed to determine the postnatal development of the kid coagulation system. Ten clinically healthy and fullterm-
born Maltese kid goats (5 males and 5 females) were used. In each kid, during the first week after birth,
the prothrombin time (PT), the activated partial thromboplastin time (aPTT), the thrombin time (TT), and
fibrinogen were assessed. Analysis of variance showed a highly significant effect of age on PT, TT, and
fibrinogen. Our results of this study indicate that the clotting mechanism in kids is influenced by growth. This
investigation contributes to the knowledge of clotting adaptations in kids during the first 7 days of life and
provides useful information for the diagnosis and treatment of some neonatal diseases
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