The Influence of Calcium Intake During the Period of Sexual Maturation of Pullets on its Retention and Eggshell Quality of Laying Hens

The aim of the study was to determine the calcium requirements in preparation period of the sexual mature and egg-laying and evaluate development of calcium retention in the first laying period of the hybrid combination Bovans Brown hens. The experimental trial lasted from 14 to 30 weeks of hens age. The animals were fed ad libitum with a pelleted complete feed mixture with 42 g/kg of calcium content. The amount of calcium retained by pullets gradually increased along with feed intake depending on age and preparation for sexual maturity and was around 0.39 +- 0.19 g Ca in the first period. Ca retention increased up to an average of 0.85 g Ca from 8 day before laying the first egg. Retention dropped sharply on the day of laying the 1st egg and a negative Ca balance occurred. Shell output was 1.75 +- 0.21 g/day for the beginning of laying and subsequently increased to 2.23 +- 0.08 g/ day during evaluate peak laying. The range weight of the first laid eggs was 45 +- 5 g. Percentage of eggshell move around an average of 10 +- 0.37% throughout the observed period. The daily calcium intake of pullets was 3.56 +- 0.26 g/day. With the beginning of laying, the daily intake increased to an average of 4.51 +- 0.43 g/day Ca. Before reaching sexual maturity, the calcium apparent digestibility of laying hens was relatively low, averaging around 22%, but the moment the hens began to lay, the apparent calcium digestibility began to increase to an average of 50%. Feeding a non-standard feed mixture with a higher calcium content than usual in mixtures for pullets did not have a negative effect on the finishing of animal development, the onset of sexual maturity, or deterioration of the observed parameters of eggs quality.O

Microelement Supplementation in Dairy Cows by Mineral Lick

The aim of this experiment was to verify the option of providing microelement supplementation to dairy cows in the dry period through supplemented mineral lick, and then to compare the content of microelements in the blood, colostrum and milk. The experiment was carried out on a farm with Czech Fleckvieh dairy cows. We formed an experimental group (E), supplied with mineral lick ad libitum enhanced with organic forms of microelements (Se, Zn, Cu, Mn) for four to five weeks before parturition and 1 week after parturition. The control group (C) did not receive any mineral lick. The use of mineral lick by cows was very uneven, its total consumption oscillated between 0 to 250 g of lick per animal per day. Lick feeding did not result in evidential increase of concentrations of monitored microelements in the cows’ blood, colostrum and milk. Only a tendency to increased concentrations of Se and Cu in the blood of group E of cows was observed; the average Se concentration increased by 60 μg l-1 (Cu by 9 μmol l-1), whereas in group C, Se increased only by 30 μg l-1 (Cu by 6 μg l-1). The concentration of microelements in colostrum after parturition dropped quickly. Significant drops were determined for Se, Cu and Zn on the first (for Mn on the second) day after parturition. Selenium concentration in the first colostrum was 5 times higher than in milk, Cu concentration 3 times higher, Zn concentration 4 times higher and Mn concentration 1.3 times higher

Titres of Specific Antibodies against Toxoplasma gondii in Goats and their Kids

The aim of our study was to perform repeated determination of specific antibody levels in mothers and their kids in order to assess indirectly the possibility of vertical transmission of toxoplasmosis in goats. Twenty-eight goats with their kids were included in the study. The following variables were assessed: number of born kids in relation to antibody titres of goats; levels of specific antibodies in the blood of goats and kids; and concentrations of immunoglobulins (Ig), total protein (TP) and total globulins (G) in order to define the end of colostral immunity and the start of active production of antibodies in kids under 69 days of age. Specific antibodies against Toxoplasma gondii in goats were detected by IFAT in titres ranging from 0 to 1 280. Out of a total of 28 animals, 5 goats were negative (17.9%) and 23 goats were seropositive (82.1%). The goats delivered 42 kids. A total ratio of number of kids to number of mothers was 1.5. Partial evaluation of results in goats without positive titre against T. gondii before parturition and goats with positive titre showed that negative goats tended to have more kids (p p < 0.01) of monitored non-specific immunity indicators. During this period, we observed increased titres of specific antibodies against toxoplasmosis in 20 kids (5 kids 41 days old, 5 kids 55 days old, and 10 kids 69 days old) and thus we could assume the possibility of vertical transmission of toxoplasmosis

Changes in the somatic cells counts and total bacterial counts in raw goat milk during lactation and their relationships to selected milk traits

The main aim of our study was to assess changes in the somatic cell count (SCC) and total bacterial count (TBC) in the raw milk of White Short-haired (WSH) goats (n = 13) during lactation and their relationships to daily milk yield (DMY), basic milk components, the acidity of milk and California mastitis test (CMT). All monitored goats were in the second lactation and throughout the study, all these goats were clinically healthy. Individual milk recording and sampling of each goat during lactation were carried, from the end of April to October on the mean 54, 89, 124, 159, 194 and 229 day of lactation and all monitored goats were milked by hand. Throughout lactation, the mean values of Log SCC ranged from 5.60 to 5.91 and the mean values of Log TBC from 2.85 to 3.58, whilst the SL had no significant effect on any of these traits. The Log SCC had a significant positive correlation (p &lt;= .01) only with CMT, which suggests that CMT may be a good predictor of the SCC. On the other hand, all correlations of Log TBC with all other traits were insignificant. Regarding the effect of the SL on all other monitored traits, it had a highly significant effect (p &lt;= .01) on the DMY, contents of fat and total protein and titratable acidity. The SL had also a significant effect (p &lt;= .05) on the pH. Nevertheless, the SL had no significant effect on lactose content and CMT. The results of our study suggest that in clinically healthy WSH goats, the SCCs in goat milk after milking should only rarely be higher than 1,000,000 cells/mL and if strict milking hygiene is applied, the TBCs should be significantly lower than 500,000 cfu/mL. The present study also suggests that the SCCs in milk in WSH goats are comparable to their counts in most other breeds.O

The effect of calcium and magnesium supplementation on performance and bone strength of broiler chickens

Aim of the experiment was evaluation of the effect of reduced calcium and magnesium content in the broiler chickens diet on its parameters of fattening, bone strength and calcium and magnesium content in liver. The trial was performed with cockerels of Ross 308 hybrid (n = 160) which were fattened in cage batteries from day 11th to 36th day of age. Cockerels were divided into 4 groups (differ in various intake levels of calcium and magnesium) in four replications. The maize-wheat-soybean basal diet contained 2.33 g Ca and 1.58 g Mg per kilogram. Calcium was added by CaCO3 and magnesium by MgSO4. Control group (C) received feed mixture with added CaCO3 in dose of 19.49 g.kg-1 and 0.41 g.kg-1 of MgSO4. Three experimental groups contain added CaCO3 in dose of 11.83 g.kg-1 and 0 g.kg-1 MgSO4 (group Exp1); CaCO3 11.83 g.kg-1 and 0.41 g.kg-1 MgSO4 (group Exp2); CaCO3 19.49 g.kg-1 and 0 g.kg-1 MgSO4 (group Exp3), respectively. The feed consumption was daily monitored and the cockerels were weighed twice a week. At the end of the study the experimental animals were weighted and slaughtered by decapitation. The weight of carcasses, liver and proportion of breast and thigh muscle was determined in the selected chickens (n = 24). The atomic absorption spectrometry was used for Ca and Mg evaluation in liver tissues. Bone strength parameter was measured at the femur bone. The statistically significant differences (p >0.05) were not detected between control and experimental groups in the case of studied parameters of fattening, bone strength and calcium and magnesium content in the chicken's liver. Based on the obtained results it could be concluded the reduction of determined elements in the chicken diet did not deteriorate parameters of yield, elements content in liver tissue as well as the bone strength of broiler chickens.O

The effect of feeding milk thistle seed cakes on quality indicators of broiler chickens meat

This study was conducted to evaluate the effect of feeding milk thistle (Silybum marianum L.) seed cakes at dose 5% and 15% in feed mixture on quality indicators of broiler chickens meat. The used milk thistle seed cakes contained 3.73% of flavonolignans and 129.83 mg.kg-1 of cyanidin-3-glucoside. A 150 cockerels of Ross 308 were divided into three equal groups. The chickens were fattened on conventional deep litter system. The experimental groups received feed mixtures containing 5% of milk thistle seed cakes (MT5), 15% of milk thistle seed cakes (MT15) and third group was control - without milk thistle seed cakes (C). The trial lasted 37 days. At the end of trial was observed significant higher average weight of chickens (2,320.31 g) in control group. Compare to that the experimental group MT5 achieved significant lower mean bodyweight 2,166.69 g. From the perspective of fattening was decreased growth of chickens where a higher percentage of milk thistle seed cakes (MT15). The group MT15 was up to 420 g lower slaughter weight compared to the control group. This was probably due to the higher content of fiber in the feed. At the end of experiment 15 birds were selected randomly from each group, weighed and slaughtered. Feathers were removed and chickens were eviscerated. Carcass yield was calculated for each group like as percentage of live weight. The MT5 and MT15 group had significantly higher breast meat tenderness that the control group. Initial pH1 was highest in group with its middle addition of milk thistle seed cakes (MT5). Significant differences were not observed between control and group MT15. Breast meat was rated as the best in parameter flavour in control and MT15 group. The thigh meat was evaluated significantly best for colour parameter in MT15 group. Fibreness was rated as the finest in MT15 group. The addition of milk thistle seed cakes do not worsened sensory characteristic of breast or thigh meat of broilers and reflects optimal sensory quality traits

Caraway (Carum carvi L.) in Fast-growing and Slow-Growing Broiler Chickens' Diets and its Effect on Performance, Digestive Tract Morphology and Blood Biochemical Profile

The aim of this study was to evaluate the addition of caraway (1%) in fast-growing and slow-growing broiler chickens' diet and its effect on performance parameters, blood biochemical profile, and relative organ sizes and ileum morphology in slow-growing broilers. Two separated experiments were performed. On the first day of age, the broilers were divided into two equal groups (Control and Caraway) with six replicates per treatment in both experiments. Experiment I: The total of 276 male fast-growing Ross 308 broiler chickens were used. The trial lasted from the first day to 35th day of chickens' age. Experiment II: The total of 216 male slow-growing (Hubbard JA 57) broilers were used. The trial lasted from the first to 50th day of chickens' age. Mean liveweight, weight gain, feed conversion ratio, blood biochemical parameters and relative organ sizes were not significantly different in these trials. The group of slow-growing broilers supplemented with 1% of caraway in the diet showed longer villi and deeper crypt in the ileum after 50 days of life. Based on our results, it can be stated that the proportion of 1% caraway in fast-growing and slow-growing broiler chickens' diet did not influence performance parameters, blood biochemical profile and relative organ sizes. In case of the experiment with the slow-growing broilers supplemented with caraway, a significant difference in the height of the villi and the depth of the crypts was found. Caraway can be included in the broiler chickens' diets without negative effects, but further study of the effect on the intestinal morphology is necessary.O

The Influence of Zinc in Nutrition on Meat Quality of Young Goats

A total of 22 young goats were used to assess the effect of two organic zinc sources, i.e. Zn lactate and Zn chelate, compared with Zn oxide and a control treatment without Zn supplementation on meat quality and zinc concentration in muscle. Muscle pH and colour (L*– lightness, a* – redness, b* – yellowness) were determined in the triceps brachii muscles, immediately after slaughter and chilling (24 h). Zn content, chemical composition (dry matter, fat, protein and collagen content), drip losses, cook losses, hardness, cohesiveness, pH (48 h) and colour (48 h) were determined. We did not found statistical significant differences in meat quality between treatments. Significant difference was found in concentration of Zn only between control and group receiving Zn oxide (P < 0.05)

The effect of feeding wheat varieties with different grain pigmentation on growth performance, texture, colour and meat sensory traits of broiler chickens

The feeding effect of of three spring wheat genotypes (V&aacute;nek, Konini and UC66049) with different grain colour on growth performance, body composition and meat quality parameters of broiler chickens was tested. Ninety chickens were divided into three groups (control, Konini and UC) with 30 chickens in each. The tested genotypes were compares with standard variety V&aacute;nek (control) with common (red) grain colour. The two experimental groups received feed mixtures containing 38.2% of wheats with different grain colour: groups Konini (n = 30) and UC (n = 30) with. The third group (n = 30) had 38.2% of common wheat V&aacute;nek cultivar (Control group). The live weight of chickens between the experimental groups and control group was not significant different, as well as body composition and chemical analysis of breast and thigh meat of chickens. The feeding of wheat with different grain colour had no effect on performance parameters of broiler chickens. Breast meat tenderness according to the Razor Blade Shear Force was higher in control group against experimental groups. The colour change was not significantly different in all coordinates. pH values (measured after 1-hour post mortem) were found significantly higher in the group fattening with Konini wheat than control and UC groups. Chickens meat from the experimental group was characterised by steady overall quality. The effect of various feeding had no effect on meat quality in terms of relevance to consumers

The effect of hempseed expellers on selected quality indicators of broiler chicken's meat

The aim of the study was to evaluate the effect of feeding hempseed expellers in a feed mixture on the quality indicators of broiler chicken's meat. One hundred and fifty Ross 308 hybrid cockerels were used in the present study. The control group (HS0) was fed without hempseed expellers; the other two groups received diets containing 50 g.kg-1 and 150 g.kg-1 of hempseed expellers (HS5 and HS15, respectively). The birds were slaughtered at the age of 37 days, and samples of breast and thigh muscles were collected for determination of proximate chemical composition and technological properties, and sensory analyses. Feeding with hempseed expellers influenced the colour of meat with a significant difference observed for a* (redness) and b* (yellowness) values in the HS15 group. The colour of breast meat in HS15 group is more intense compared to HS5 and HS0 groups. Breast meat was evaluated as the best in terms of odour for HS15 group compared to HS0. The colour of thigh meat was better rated in the HSE supplemented groups compared to the controls. In conclusion, dietary supplementation with hempseed expellers appears to affect the colour and odour of broiler chicken's meat which is positive for the consumers. Including hempseed cakes can be recommended as a component of broiler chicken's feed.O