Jan Trávníček

Effect Of Organic Selenium And Iodine Supplementation On Selenium And Thyroid Hormones Status Of Lactating Ewes And Lambs

Abstract The aim of this research was to determine the influence of 56-days (from day 4 to day 60 post partum) of simultaneous supplementation of selenium (Se) and iodine (I) enriched Chlorella algae on blood and urine Se concentrations and thyroid hormone levels in ewes and lambs. The study included 18 Šumava sheep ewes and their lambs divided into three groups (CON, HSe, HSeI). Selenium and I content in the diet of ewes measured 0.2 and 0.7 mg (CON), 0.4 and 0.7 mg (HSe), 0.4 and 1.3 mg (HSeI) per kg of dry matter. During the experimental period a significantly higher blood serum Se concentration was determined in ewes of the HSeI group (P< 0.001) and urine (P< 0.01). A significantly higher (P< 0.001) blood serum Se concentration was found also in lambs of the HSeI group. The highest Se concentration in the blood serum was recorded in ewes (128.0 μg/L) and lambs (74.2 μg/L) on the 26th day of the experiment. The results demonstrate a higher utilization of Se administered in the organic form accompanied by a higher intake of I applied also in the organic form. Plasma thyroid hormone levels in ewes were not explicitly affected by higher Se and I supplementation. A higher Se concentration in the lambs’ blood serum led to significantly higher (P< 0.05) T3 levels up to 30 days post birth.

Morphological and histometric parameters of the thyroid gland in slaughter cattle

Morphological and histometric parameters of the thyroid gland in slaughter cattle The study presents an evaluation of morphological and histometric parameters of the thyroid gland of slaughtered cattle (29 cows, 10 bulls, 7 heifers and 4 calves). The thyroid gland of bulls contained 34.7% of large follicles while their content in cows and heifers was 32.6% and only 19.2%, respectively. The average follicle length was 162.0±19.8 μm in bulls, 153.5±24.8 μm in cows and 122.4±10.1 μm in heifers. The highest thyreocytes were found in heifers and bulls (9.45±1.17 and 9.42±1.50 μm, respectively) and the lowest in cows (8.46±2.13 μm). A positive relationship was determined between the iodine content of the thyroid gland and the percentage of large follicles (r = 0.55) while the relationship between iodine content and thyreocyte height was negative (r = -0.21). In the thyroid gland of older cows medium and large follicles with low cubic to flat thyreocytes were dominant. Some follicles contained necrotic thyreocytes and the cytoplasm contained lipofuscin. The results suggest the influence of an increased iodine content in the thyroid gland on follicle size and thyreocyte height.

Influence of age, gender and sire line on young cattle behaviour traits.

The aim of this study was to test effects of age, gender, and sire line on dairy cattle behaviour. We have analyzed results of ethological tests for 40 Holstein breed animals (23 males and 17 females), offsprings of three sires. Maintenance behaviour were observed at the age of 90, 130 and 170 days. Behaviour in the maze was conducted at the age of 119 days, an open-field test was applied at the age of 124, 168, and 355 days. The social behaviour was determined by feeding on 155th day of the age. The times and the number of periods in all activities of maintenance behaviour were changing significantly (P<0.001) according to the age. The total time of lying, lying with ruminating, ruminating, feeding was increasing from the age of 90 days to the age of 170 days, on the other hand the time of standing was decreasing. The times of total lying, lying with ruminating, total ruminating, feeding were increased, and time of standing was decreased from the age of 90 days to the age of 170 days. Calves spent more time lying on the left side than on the right side. The number of ruminating periods was increasing according to the age. Eating periods were decreasing from the age of 90 to 170 days. The most of lying periods were recorded at the age of 130 days. The differences between sex were found in total time of lying, lying on the right side (P<0.05), and the males rest longer and had more periods of lying than females. We have found differences in times of feeding (P<0.001), total lying, standing (P<0.01), and lying on the left side (P<0.05) according to sire by comparing behaviour of the calves. Sire genotypes were significantly manifested in period number of total lying (P<0.001), lying on the right side, feeding (P<0.01), and standing (P<0.05). Males stood in the first part of maze longer than females (P<0.001), also length of total standing was longer by bulls (P<0.01). Heifers took shorter time to leave the maze than bulls (P<0.05). Sire lineages significantly differed in times of standing in the first part of maze and maze leaving. We did not find any significant differences either among sire lineage groups or between genders in locomotor behaviour measured by the number of crossed squares in open-field test. During all observations were more mobile heifers. No significant differences were found between males and females in social behaviour. The sire line influenced only the number of total duels (P<0.001). We found significant positive relationship between live body weight and time of staying in the first part of maze (r=0.3957**), time of maze leaving (r=0.3720**), and number of total and win duels (0.4031**, 0.3216*). Significant relationships were recorded in almost maintenance behaviour activities (P<0.001). Consistency of locomotor behaviour was proved only between the ages of 124 and 168 days (r=0.3177*). Significant relationship between maze behaviours and number of crossed squares were found only in ages of 119 and 124 days (r=-0.3721**; r=- 0.4110**; r=-0.3994**).

The influence of high selenium intake of ewes on leukocytes in newborn lambs.

Abstract The aim of this work was to determine the impact of high selenium intake on pregnant ewes considering the number of leukocytes and the representation of T cell subsets in the blood of newborn lambs. An experiment was conducted on nineteen sucking newborn lambs of the Sumava sheep breed. The ewes were divided into three groups of five animals: control C (without Se supplementation), experimental E1 (sodium selenite supplementation, Se content 160 μg.kg-1 DM) and E2 (Chlorella as a carrier for selenium, Se content 160 μg.kg-1 DM). After birth blood samples were taken from lambs on days 1, 3, 10, 30 and 60. The WBC count and proportion of lymphocytes in blood smear were detected by microscopic analysis, and the CD4+ and CD8+ T cell subsets in blood were detected by flow cytometry. The differences determined were not statistically significant due to high variabilities within the groups. In lambs whose mothers were supplemented with selenium bound to the alga of the genus Chlorella a statistically significant increase in the proportion of both subsets of T lymphocytes was proved. The results document a tendency to a lower level of the selected parameters of immunity in lambs without Se supplementation.

Effect of High Iodine Intake on Selected Parameters of Immunity in Sheep

Abstract The study aimed at defining the immunity risks connected with high iodine supplementation in ewes and their lambs. The feed ration for control group (C) of ewes (n=6) contained 3.1 mg of iodine per kilogram of dietary dry matter and for experimental group (E) of ewes (n=6) 5.1 mg of iodine per kilogram of dietary dry matter. The animals were fed the diets for 8 months. Parallelly with different iodine supplementation, some immunological parameters (percentage of γ-globulins, concentration of immunoglobulin G, and white blood cell count) were examined in ewes and their lambs. The difference in the average concentration of immunoglobulin G between the ewes of group C and E was not significant during the experiment. A significant decrease (P<0.01) in the concentration of immunoglobulin G from 19.6 mg/mL before the experiment to 9.8 mg/mL on day 60 of the experiment was demonstrated in the ewes of group E. The average percentage of γ-globulins in the whole period after parturition was lower in the ewes of group E than in group C. The concentration of immunoglobulin G and the percentage of γ-globulins in lambs from dams in group E was continually lower (P<0.01) for the entire period of 1-30 d and demonstrated immunological risks of the excessive intake of iodine. The obtained results document a dangerous influence of high iodine intake on immunity in the prenatal period in ewes and mainly in the postnatal period in their lambs.

Antibody production in sheep fed a diet containing brown seaweed

Antibody production in sheep fed a diet containing brown seaweed The study is aimed to determine the effects of brown seaweed supplement in diet on immunoglobulin (IgG) and specific tetanus toxoid (TT) antibody production in gimmers. The experiment took 280 days. The experimental group E (n=6) was given 71 mg of brown seaweed in its daily diet for the whole period of the experiment, whereas the control group had no supplements in its diet. On the 245th day of the experiment the animals were vaccinated with TT to find out if the levels of antibody production would vary. The revaccination of TT was done 15 days after that. Blood samples were collected 7, 14, 21, 30 and 35 days after the first vaccination. During the study no significant differences of IgG were recorded in the blood serum between group E and C. The results suggest, in agreement with findings of other authors, that the specific TT antibody production decreases by 16% to normal during brown seaweed feeding and should be taken in consideration during targeted immunization.

Effects of High Temperatures on Milk Production of Dairy Cows in East Central Europe

Summer climates causes stress in dairy cows leading to depress production. Heat stress increases maintenance energy requirements, lowers dry matter intake, especially forage intake, making it difficult to meet energy needs. The most noted negative effects of heat stress are decreased milk yield. The objective of this paper was to evaluate the effect of high temperatures on dairy cow milk production in southern Slovakia. We tested the hypotheses that the milk yield is impacted by the breed (Red Holstein, Slovakian Pied cattle and Holstein) and by the cooling (fan or fogger+fan), and the season. Production data included 57,927 test-day records belonging to 20 herds. Four herds were Red Holstein cattle (9,365 records), 8 herds had Slovakian Pied cattle (22,936 records), and cows of Holstein breed were in 8 herds (25,626 records). All herds were situated in lowlands, from 130 m to 182 m above sea level. Herds were distributed according to cooling of cows during high temperatures. First group of cows (10 herds) was evaporative cooled before milking by water spray cooling equipment installed in the holding pen twice daily. Second group of cows (10 herds) was cooled using only forced ventilation (automatically controlled fans without misting in housing and feeding areas). In the months June to August were recorded 84 summer and 50 tropical days. Eighty four days were with the temperature-humidity index above 72.0 and 50 days above 78.0. The highest performance for the year was found in Holstein cows (9637.8 ± 405.0 kg; P<0.01). Evaporative cooled cows produced more milk than non-cooled (9234.4 ± 387.8 versus 8288.4 ± 392.7 kg; P<0.001). The average monthly milk yield was non-significantly higher in evaporative cooled cows for the whole period with high temperatures (from May to September). The highest milk production per month was found in Holstein cows and the lowest in Slovakian Pied cattle (P<0.05). In the season comparison, the highest production was recorded in the period January-April (P<0.001).

Effect of the Season at the Birth on the Performance and Health of Calves

Heat stress negatively affected production by hutch calves. Summertime heat adversely affects productivity by the decreased feed intake and daily gain. The objective of this paper was evaluate effects of high temperatures on the growth, feed consumption and health condition of calves kept in individual hutches in southern Slovakia (East Central Europe). We tested a hypothesis that the calf performance would be influenced by the season at birth, sire lineage and gender. Sixty-three Holstein calves were used. They were reared in individual hutches from the second day of life to weaning at the age of 8 weeks and then in group pens. The calves originated from 5 sires. All calves were divided according to the season at birth. The same conditions of nutrition were ensured. Feed and water refusals were removed and weighed back each morning. Air temperature and relative humidity were accurately recorded during the entire 24 hour periods. Fluidity, color, consistency, odor of feces and health condition was evaluated two times daily. The data were analyzed using a GLM ANOVA. We recorded 52 summer days and 14 tropical days for this summer period. Eighteen days with the THI value above 72.0 were found in the June, in the months July and August we found 22 and 26 these days. The total number of days with the THI values higher than 78.0 was twenty-six for summer period. The calves born during the summer had the lowest live body weight from the first week to the 90th day of age. The highest growth was recorded in calves born in the fall. A significant difference was detected also for the period from birth to weaning (P<0.01). The tendency of lower growth of calves born in summer was confirmed in the period to the 180th day of life. Calves born in the spring drank up 36.4 kg of water to the weaning, calves born in the summer drank up 73.6 kg, and calves born in the fall drank up 54.2 kg of water. However, we did not obtain sufficient evidence of effects exerted by the sire lineage and gender. No significant differences were found in parameters of health and feces.