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The ribosomal protein SA (RPSA), also known as 37-kDa laminin receptor precursor/67-kDa laminin receptor (LRP/LR), has been identified as a multifunctional protein, playing an important role in multiple pathologies like cancer and prion diseases. Since RPSA is involved in the binding and internalization of the prion protein, mutations in the ovine RPSA gene, influencing the RPSA-PrP^C/PrP^Sc binding, can potentially play a part in the resistance to prion diseases. Our goal was to further characterize the complex RPSA gene family and to detect structural mutations which can play a role in this disease. In a prior study, 11 ovine pseudogenes were detected experimentally. As the whole genome shotgun ovine genome became accessible, an in silico genome-wide screening was performed and 37 new pseudogenes (36 processed and one semi-processed pseudogene) were detected, bringing the total to 48 ovine RPSA pseudogenes. Additionally, the complete bovine genome was screened in silico and 56 pseudogenes were identified. Once these sequences were known, it was possible to analyze the presence of mutations in the coding sequence and exon-flanking regions of the ovine functional full-length RPSA gene without the interference of pseudogenic sequences. Nineteen mutations were found: one in the 5' UTR, a silent one in the coding region, and seventeen in the exon-flanking regions, including an interesting mutation in the SNORA62 gene, localized in intron 4 of RPSA, leading to potential ribosomal defects. Structural mutations of the RPSA gene can be ruled out to play a role in transmissible spongiform encephalopathies but regulatory mutations still can have an effect on these diseases.

A comparative analysis of reproduction parameters and hatchability results of pheasants raised under two different housing systems (cages and aviaries) was performed. In the first system the pheasants were housed in 420 cages, 3780 from the total were females. In the second housing system, 3200 pheasant hens were placed in eight aviaries, where 50 cocks and 400 hens were kept in each. The following parameters were calculated: laying rate, the percentage of hatching, small and cracked eggs, hatchability from set and fertilized eggs, dead embryos up to day 8 of incubation and, finally, dead embryos after day 8 of incubation as well as unhatched, crippled, and weak chicks. The laying rate for the whole period of reproduction in pheasants kept in cages was significantly higher in comparison with aviaries (59.6 vs 27.2%). A higher (P ≤ 0.05) percentage of small and damaged eggs ( = 13.6) was recorded in aviaries. The percentage of dead embryos for eggs derived from aviaries, up to day 8 of incubation, was also significantly higher (-x = 4.7%). There were no significant differences between the housing systems with respect to the remaining features. The results of the investigation made it possible to conclude that pheasants kept in cages were characterized by a higher laying performance with fewer eggs unsuitable for incubation. A lower mortality of embryos during the incubation process was found in eggs derived from pheasants reared in cages. Although there were no significant differences between the analyzed housing systems in terms of hatchability, a higher laying rate for pheasants kept in cages implies that more chicks could be obtained from every female.

Freemartinism, a primary disorder of sex development (DSD) in cattle, is associated with leukocyte chimerism (60,XX/60,XY). The diagnosis of DSD is easy if it is known that a heifer with abnormally developed reproductive tracts originates from a heterosexual twin birth, but it is not so obvious in the case of single born calves. In the present study twelve DSD heifers which were single born (singletons) and culled due to the abnormal development of internal genitalia were studied using cytogenetic and molecular techniques. Among the heifers 7 appeared to be chimeric (60,XX/60,XY and the presence of the genes residing in the Y chromosome: SRY and AMELY) and 5 had a normal female karyotype (60,XX and a lack of the Y-linked genes). In addition, milk productivity was analyzed in relation to the incidence of twinning at a local Dairy Cattle Breeding Centre, from which 8 studied singletons (6 chimeric and 2 with a normal female karyotype) originated. It was found that in the years 2005-2013 an upward trend for average milk yield (from 9700 kg in 2005 to 11 500 kg in 2013) was associated with the increase of twin births (from 1.5% in 2005 to 5.9% in 2013). Our study showed that approximately 60% of single born heifers with abnormally developed internal genitalia were freemartins (a male co-twin died during pregnancy), while DSD etiology of the other cases (60,XX and a lack of the Y-linked genes) remains unknown. It cannot be excluded that some of these heifers represent a testicular/ovotesticular DSD (60,XX and SRY-negative). In conclusion, our study suggests that the occurrence of freemartins and other DSD in single born heifers seems to be an underestimated problem in cattle breeding.

Spermatozoa morphology, ultrastructure, and spermatozoa motility traits were studied in pikeperch (Sander lucioperca) after activation in various media (AM 1 - 45mM NaCl, 5mM KCl, 20mM Tris, pH 8.5; AM 2 - 100mM sucrose, 20mM Tris, pH 8.5; AM 3 - 100mM sucrose, 1mM CaCl₂, 20mM Tris, pH 8.5) during a 48-hour storage period. The spermatozoon was acrosomeless and differentiated into a spherical nucleus (head), midpiece, and flagellum. The nucleus length and width measured 1.83 ± 0.03 and 1.63 ± 0.02 mm, respectively. The midpiece was located laterally to the nucleus and possessed proximal and distal centrioles and 2-4 mitochondria. Flagellar length was 33.2 ± 0.90 µm, and a pair of lateral fin-like structures projections was observed. The axoneme consisted of nine peripheral doublet microtubules and a single central pair. After a 24 h storage in all activation media at all sampling times post-activation (15, 45, 90, and 120 s), spermatozoa motility was significantly decreased. Spermatozoa were motile after the 48-hour storage at all sampling times post-activation only in AM 3. After the 48-hour storage, no motile spermatozoa were observed in AM 2 and AM 1 at 90 and 120 s post-activation, respectively. Differences in spermatozoa velocity varied with activation medium during storage. After the 48-hour storage in AM 1 and AM 2, decrease of spermatozoa velocity at 15 s post-activation was observed, while in AM 3, velocity was decreased only after the 48-hour storage. Pikeperch spermatozoa morphology and ultrastructure was found similar to that of most freshwater teleosts, with differences in the arrangement of midpiece, number of mitochondria, and position of centrioles. Viable pikeperch sperm was observed after the 48-hour storage. Motility of spermatozoa was improved by addition of Ca²⁺ to the activation medium, where higher spermatozoa velocity was observed.

The objective of the present study was to determine the association between the uterine size and age, body weight, growth rate, and reproductive status in Landrace × Yorkshire crossbred gilts. Genital organs from 310 gilts (302.6 ± 2.9 days of age, 145.2 ± 1.2 kg body weight) were examined. The gilts were classified into two groups according to reproductive status: non-cyclic (n = 86) and cyclic (n = 224). The uterine weight in non-cyclic gilts was lower than that in cyclic ones (128 ± 8.1 and 694 ± 17.9 g, P < 0.001). Likewise, the length of the uterus in non-cyclic gilts was shorter than that in cyclic gilts (123 ± 2.9 and 252 ± 4.6 cm, P < 0.001). The weight of the uteri correlated with the body weight (r = 0.48, P < 0.001) and growth rate (r = 0.33, P < 0.001) of the gilts but not with their age (P > 0.05). For every 10 kg increase in the body weight of the gilts, an increase of 67 g in uterine weight (P < 0.001) and 21 cm in uterine length (P < 0.001) was observed.

The objective of this study was to estimate heritabilities and genetic correlations of lactational and daily somatic cell scores with descriptive and linear type traits in Polish Holstein-Friesian cows. Data were: test-day somatic cell scores and conformation evaluations of 24 599 primiparous cows, daughters of 802 sires. Cows calved from 2006 to 2007. The lactational somatic cell score was calculated as the average of four test-day somatic cell scores at least. The daily somatic cell score was the test-day somatic cell score closest to the date of type evaluation. A multi-trait animal model was used to estimate genetic parameters. (Co)variance components were estimated by a Bayesian algorithm via Gibbs sampling. The heritability of lactational somatic cell score was 0.20 and it was much higher than that of daily somatic cell score (0.13). Heritabilities of type traits were high to moderate for height at rump (0.46), size (0.39), overall conformation score (0.30), two linear rump traits (0.28-0.29) and three linear teat traits (0.26-0.29). The genetic correlation between lactational and daily somatic cell scores was 0.84. In many cases, daily somatic cell score showed higher genetic correlations with type traits than lactational somatic cell score. Descriptive udder and feet and legs scores were genetically correlated negatively with both lactational (-0.22 and -0.20) and daily somatic cell scores (-0.28 and -0.33). Somatic cell traits were genetically correlated positively with rump angle (0.21 and 0.19) and negatively with fore udder height (-0.26 and -0.29), udder depth (-0.23 and -0.17) and central ligament (-0.14 and -0.16). Due to higher heritability, direct selection for lower lactational somatic cell score would be more effective than selection for lower daily somatic cell score. The magnitude of obtained heritabilities and the favourable genetic correlations indicate that the selection utilizing some type traits could improve the resistance to mastitis.

A multiple-lactation random regression model was applied to test-day somatic cell score (SCS) records from the first three lactations of Czech Holstein and Fleckvieh cows. For Holstein, the data included 26 314 cows, with 244 953, 76 188 and 26 153 test-day records in the first, second and third lactation, respectively. For Fleckvieh, the data included 24 061 cows, with 223 421, 93 358 and 31 305 test-day records in the first, second and third lactation, respectively. The linear model for SCS included the following factors (for the given parity): fixed herd-test date effect, fixed regressions on days in milk within the age-season class, random regressions for the animal genetic and random regressions for the permanent environmental effect of the cow. Third-degree Legendre polynomials were used for all regressions. Gibbs sampling was used to generate samples from the marginal posterior distributions of the model parameters. The resulting daily heritability ranged from 0.08 to 0.11 in the middle part of lactation and it increased only slightly with parity. Extremely high values (0.25, 0.21) observed especially at the beginning and end of the third lactation for Holstein might be caused by the "end-of-range" problem. The average daily heritabilities computed for the part of lactation between 45 and 255 days in milk (DIM) were in the range from 0.10 to 0.14. Daily permanent environmental variances were higher than the genetic variances and daily residual variances decreased with DIM. The residual variances in early lactation increased with lactation number. For both breeds, the highest genetic correlations computed for the part of lactation between DIM 45 and DIM 255 were obtained between the second and third lactation (0.95). The lowest daily genetic correlations of SCS in the same DIM between different lactations occurred at the beginning of lactation, especially between the first and third lactation. The permanent environmental correlations for selected DIM were lower than the respective genetic correlations.

The aim of the study was to evaluate the effect of organic acids and the prebiotic fructans on egg production and eggshell quality when added to the layer diet with different levels of calcium and phosphorus. The experiment was carried out on 168 Bovans Brown hens, allocated to 14 groups of 12 replications. Each hen (replication) was kept in an individual cage 40 cm × 40 cm in size. A 2 × 7 factorial arrangement, with two dietary levels of calcium and phosphorus (normal - 3.70% Ca, 0.65% P, and reduced - 3.25% Ca, 0.60% P) and with diets supplemented by selected additives (none, 0.75% inulin, 0.75% oligofructose, 0.50% volatile fatty acids (VFA), 0.25% medium chain fatty acid (MCFA), 0.30% VFA + 0.20% MCFA, 0.75% inulin + 0.50% VFA) was used. The experiment was carried out over 34 weeks, from the age of 26 to 70 weeks. There were no statistically confirmed effects of the factors studied in this experiment on egg performance, i.e. laying rate, egg mass, feed intake and feed conversion. Reducing the dietary levels of Ca and P significantly decreased eggshell percent, thickness, density and breaking strength. The additives used had a considerable effect on eggshell quality at 46, 58 and 70 weeks of age, and these positive effects were most pronounced in the case of inulin and MCFA. There was no significant interaction between Ca and P dietary levels and the additives used. It was thus concluded that selected feed additives which lower the pH of the diet and intestinal content can beneficially influence eggshell quality in older high-producing laying hens.

An experiment was carried out on four dry Holstein cows fitted with rumen cannulas that were divided into two groups. The crossover design experiment was divided into 4 periods of 3 weeks. Each period consisted of a 17-day preliminary period followed by a 4-day experimental period. Cows were fed twice daily the total mixed ration based on maize silage and concentrate. Control cows (Control) received the basal diets while experimental animals (Yeast) received the basal diet supplemented with 3.0 g of live yeast (BIOSAF Sc 47, Lesaffre, France) at each feeding. During each experimental period ruminal pH and redox potential (Eh) were monitored continuously using a developed wireless probe. Further, in each experimental period five samples of ruminal fluid were taken at 6:30, 8:30, 10:30, 13:30 and 16:30 h to determine the content of volatile fatty acids, lactic acids and ammonia. On the last day of each period, blood samples were taken for determination of blood parameters and acid-base balance. Average daily dry matter intake throughout the experiment was 8.2 kg/day and was not affected by the treatment. The average ruminal pH in Control was 6.16 that was significantly lower than in Yeast, being 6.26 (P < 0.001). The diurnal pattern of ruminal pH showed a similar trend in both groups. Mean Eh in Control (-210 mV) differed significantly from Yeast (-223 mV, P < 0.001). The mean value of rH (Clark's Exponent) calculated for Control (5.33) was higher than that calculated for Yeast (5.09, P < 0.001). Total VFA concentrations were on average 40.8mM in Control and 57.2mM in Yeast (P > 0.05). Lactate and ammonia concentrations at individual sampling times and overall mean did not differ significantly between treatments (P > 0.05). Blood pH and CO₂ were not affected by the treatment.

Nitric oxide (NO) is a biological signaling molecule that plays a crucial role in oocyte maturation of mammalians. It is generated by the nitric oxide synthase (NOS) enzyme from l-arginine. Although the effect of NO has been shown in oocyte maturation of some species, there is no report about its effect on the in vitro maturation of sheep oocyte. So, this study aimed to investigate the importance of NO/NOS system in the in vitro maturation of ovine oocytes. Different concentrations of L-NAME (a NOS inhibitor) (0.1, 1 and 10mM) were added to maturation medium to evaluate the effect of inhibiting NOS on cumulus expansion and meiotic resumption of sheep oocytes. After 26 h culture, low and medium concentrations of L-NAME (0.1 and 1mM) had no significant effect on cumulus expansion, however, its higher concentration (10mM) decreased percentage of oocytes with total cumulus expansion as compared to control (P < 0.05). The extrusion of the first polar body was also suppressed in a dose-dependent manner, so that the addition of 10mM L-NAME to maturation medium significantly stopped oocytes in GV stage (P < 0.05). Moreover, to confirm the results and to evaluate if this effect is reversible, 0.1mM sodium nitroprusside (SNP, a NO donor) was added only to the maturation medium which had the highest concentration of L-NAME (10mM). The concomitant addition of NOS inhibitor with NO donor reversed the inhibitory effect of L-NAME on cumulus expansion and meiotic maturation. These results indicated that NO/NOS system is involved in the maturation of sheep oocytes.

Conflicting data still exist regarding the extent of paternal pronuclear DNA demethylation in one cell-stage mammalian embryos. Demethylation of paternal pronuclear DNA was observed in in vitro produced porcine zygotes, whereas in vitro produced embryos do not show any or only weak paternal genome demethylation. In our experiments, we have used and compared two in vitro techniques commonly used for in vitro embryo production (in vitro fertilization and intracytoplasmic sperm injection) and then we evaluated the extent of labelling in both these groups after 5-methylcytosine (5-MeC) or dimethyl H3/K9 labelling. We have found no differences in the methylation pattern between both those techniques used for the production of embryos. Moreover, we did not detect any demethylation of paternal DNA after 5-MeC labelling at all. Contrary to this, labelling with dimethyl H3/K9 antibodies showed differences in labelling intensity between maternal and paternal genomes in 42% of zygotes after in vitro fertilization and in 44% of zygotes after intracytoplasmic sperm injection. Our results indicate that in vitro matured pig oocytes exhibit rather inconsistent methylation patterns. This inconsistency probably resulted from insufficient cytoplasmic maturation of oocytes and to a lesser extent from the in vitro technique for embryo production.

In this study, 254 Escherichia coli isolates from faecal samples of veal calves were evaluated for antimicrobial susceptibility using the disk diffusion method. During the experimental period, six mass antibiotic treatments were administered to the animals (about one treatment per month). The active principles used were oxytetracycline, colistin, tylosin, doxycycline, chlortetracycline, and sulphonamides. An extremely high resistance prevalence (> 70%) towards penicillin, sulphonamide, tetracycline, ampicillin, and spyramicin was detected. Sixty E. coli isolates could be defined as multiresistant, showing resistance to at least 6 antimicrobial classes. Subsequently, we evaluated the inhibitory effect of a species-specific probiotic against multiresistant E. coli, showing its beneficial action with large inhibition halos for 76% of the isolates. This suggests the potentiality of the probiotic, putting in evidence a clear advantage of its use in veal calves nutrition, in particular during the first phases, when the animals are more susceptible to severe enteric infections by E. coli.

Thymol's antimicrobial properties urged researchers to study its effect on animal performance and intestinal health in pigs. However, thymol has the characteristic sharp odor of thyme and a bitter, aromatic, and sometimes burning sensation which may elicit feeding aversions. The objectives in the current study were: (1) to determine the effect of dose of thymol and camphor on palatability and (2) to test the hypothesis that supplemental flavours or camphor, the latter as a known Transient Receptor Potential A1 blocker, could mitigate feed avoidance caused by thymol. Two analogous choice-feeding trials were conducted. Feed intake of the test diet was expressed as proportion of the total intake and tested by means of a one-sample Student's t-test against a set value of 50%. The preference for feed supplemented with 125, 500, 1250 and 2000 mg/kg thymol was 53.7 ± 6.0% (P > 0.05), 47.5 ± 5.1% (P > 0.05), 36.8 ± 4.9% (P = 0.022), and 3.9 ± 7.9% (P = 0.005) respectively. When feed containing 2000 mg/kg thymol with either flavour A (containing intense sweeteners) or flavour B (containing the same intense sweeteners and a caramel aroma) was opposed against a control diet, the relative intake of the test diets was 19.9 ± 5.8% and 14.0 ± 4.9% (both P < 0.05) respectively. When animals were offered one of these test diets and a reference diet with 2000 mg/kg thymol, animals exhibited a preference for the feed with 2000 mg/kg thymol + flavour A, but not for the feed with 2000 mg/kg thymol + flavour B. Thus, supplemental flavours containing intense sweeteners partially overcame feed avoidance caused by thymol which was less pronounced when the caramel aroma was present. Exposure to camphor (50 and 200 mg/kg) did not improve feed preference for a diet containing 1250 mg/kg thymol. Thymol's bitter taste might be largely responsible for the recorded feed refusal at high inclusion rates.

The hypothesis that relocation of cows with a housing change temporarily decreases their milk production and affects cows' behaviour in the milking parlour has been proved. Forty-one Holstein cows on the 1^st and 2^nd lactation were relocated from the tie-stall barn into the free-stall barn. Cows were milked in a 2 × 5 herringbone parlour twice a day. Individual milk yields, order, and used parlour side were recorded electronically during 50 (milk) or 22 (order and side) milking sessions. Milk yield after cows' relocation (23.76 kg) significantly decreased if compared to that reached on the day preceding relocation (30.97 kg; P < 0.001). Milk production approached the level of the last day on days 3 and 4 (30.72 and 30.72 kg, respectively) after relocation. Milk yield exceeded that before relocation on day 13 (31.82 kg). There were significant differences between parities during the whole observation period except for the first day after relocation - cows on the 2^nd parity yielded more (P < 0.001). Multiparous cows entered the parlour earlier than primiparous, equally during morning and evening milkings (P < 0.01). Generally a left-side preference was found in the observed cows, while it was more prominent in primiparous than in multiparous cows during evening milkings (P < 0.05). Relationships between milking order and milk performance were on days 5-11 negative and significant (P < 0.01). We may conclude that although temporarily, relocation with housing and milking changes significantly affected the milk yield.

The study aimed at an evaluation of fattening and slaughter performance as well as meat quality of the native Złotnicka Spotted (ZS) pigs and its crosses with Duroc pigs. The experimental material comprised 60 fatteners, divided into three genetic groups of 20 animals (100% ZS, 75% ZS and 50% ZS). The specific character of conservative breeding results in low values of fattening and slaughter performance traits observed in ZS breed. Among the analysed groups, animals with 100% share of ZS genes in their genotype were characterised by low daily weight gains (0.59 kg), considerable backfat thickness (34.96 mm), slight muscle thickness (48.05 mm), and low leanness (41.83%). These parameters were higher in both groups of crosses. Differences between the 100% ZS group and the 50% ZS group were significant for backfat thickness and highly significant for leanness. Acidity and colour parameters analysis showed that meat from all the genetic groups analysed was characterised by a good quality. The highest pH₄₅ values were in the 75% ZS group, and meat from this group had the darkest colour (L* = 49.73) and the highest red colour share (a* = 5.11). Statistical analyses showed that ZS breed retained its original traits through the years of breeding. It was confirmed that meat of Złotnicka Spotted breed is characterised by excellent quality. The results indicate that ZS and Duroc breeds crossing improves fattening and slaughter performance, while maintaining good meat quality in their crosses. Results of this study may also be used by breeders. They indicate that crosses of both the breeds kept in extensive breeding may be successfully used in high quality meat production. Pork from such animals may be a raw material for market niche production, such as regional products. The use of meat from crosses in meat processing may improve both quality of the processed products and efficiency of production based on the native Złotnicka Spotted breed.

The study investigated the consequences of maternal undernutrition during late pregnancy on hormonal status and metabolic changes in neonatal lambs. Four ewes out of twenty-eight multiparous ewes mated at a synchronized oestrus were slaughtered at day 90 of pregnancy to collect fetal blood to serve as an initial comparison group. Twenty-four animals were divided into three groups and offered 0.18 MJ ME.kg^-0.75per day (restricted group 1, RG1), 0.33 MJ ME.kg^-0.75per day (restricted group 2, RG2), and control group (ad libitum CG) during late pregnancy, respectively. Immediately after parturition, blood was collected from the neonatal lambs in each group and analyzed for growth hormone (GH), insulin-like growth factor I (IGF-I), IGF-II, insulin (INS), thyroxine (T₄), triiodothyronine (T₃), glucose (GLU), nonesterified fatty acids (NEFA), and total amino acid (TAA), respectively. The results indicated that the maternal undernutrition during late gestation decreased the average lamb birth weight in both RG1 (P < 0.01) and RG2 (P < 0.05) compared to CG. During the late fetal development period, the concentrations of T4, INS, and IGF-I of neonatal lambs in CG were increased (P < 0.05) compared to those at day 90 of pregnancy; the secretions of T₄, INS, and IGF-I in RG1 and RG2 during restriction were suppressed. The neonatal INS concentrations in RG1 and RG2 were decreased (P < 0.05), but the neonatal GH concentration in RG1 was greater than that of CG (P < 0.05). The GLU concentrations of neonatal lambs in RG1 were lower than those of CG (P < 0.05). However, the neonatal NEFA (P < 0.05) and TAA (P < 0.01) concentrations in RG1 were greater than those of CG. Thus, maternal undernutrition can change the hormonal and metabolic status of neonatal lambs, which may have significant implications on postnatal growth and adult health.

The effects of methanolic extract of Dracaena arborea on mean testicular weight, mean cauda epididymal sperm reserve, and testicular morphology were evaluated. A total of sixty mature male Sprague Dawley rats were divided into three equal groups. The first group (A) received distilled water while the other two groups (B and C) received orally the methanolic leaf extracts of Dracaena arborea in two doses (100 and 500 mg/kg, respectively) daily for 84 days. Following oral administration of the extract, mean testicular weight, mean cauda epididymal sperm reserve, and testicular morphology were determined on days 28, 42, 56, 70, and 84. The extract produced a significant and dose-dependent increase (P < 0.05) in the sperm number. There was also a significant increase (P < 0.05) in the mean testicular weights on days 70 and 84 of the extract administration. The testicular morphology remained unchanged while further testicular histology examination revealed increased spermatogenesis. It was concluded that the methanolic leaf extract of D. arborea has fertility enhancing properties.

In this study, changes of pH, ionic (Na⁺, K⁺, Ca²⁺,and Mg²⁺), biochemical (total protein, glucose, and cholesterol)compositions of seminal plasma, sperm motility traits (percentage of motile spermatozoa and sperm movement duration), and sperm production characteristics (sperm volume, spermatocrit, and sperm density) were studied in Caspian roach, Rutilus rutilus caspicus, during spawning migration. Sperm of 10 males was collected three times during the spawning migration (in February, March, and April). The results showed that sperm motility parameters (percentage of motile spermatozoa and sperm movement duration) changed significantly (P < 0.05) during the reproductive season, but sperm density, spermatocrit, and sperm volume did not show significant differences during spawning migration. Analyses performed at each sampling time (February, March, and April) showed significant differences (P < 0.05) in calcium,magnesium, potassium, and cholesterol, whereas there were no significant changes in Na⁺, pH, total protein, glucose, and cholesterol.

The effects of sex and slaughter age on growth, feed intake, carcass composition and meat quality attributes of musculus longissimus lumborum were investigated in Charolais × Simmental bulls (n = 12) and heifers (n = 12) reared and finished under identical management conditions. The animals entered the experiment at similar age (251 days) and were slaughtered at 14 or 18 months of age. Bulls gained more rapidly (P < 0.001), consumed more dry matter daily (P < 0.05), and had a higher killing-out proportion (P < 0.05). The sex × slaughter age interaction was significant (P < 0.01) for feed conversion ratio, which deteriorated markedly more in heifers than in bulls as slaughter age increased. Bulls produced leaner carcasses with a higher proportion of total meat (P < 0.001). While bulls contributed to high-priced meat by a higher proportion of meat from the shoulder (P < 0.01), heifers had higher proportions of meat from the rump and loin (P < 0.05). Older animals were generally fatter and their carcasses contained lower proportions of high-priced meat (P < 0.01) and bones (P < 0.05). Bulls exhibited lower contents of dry matter (P < 0.001), protein (P < 0.05) and intramuscular fat (P < 0.001), and a higher content of collagen (P < 0.001) in musculus longissimus lumborum than hei-fers. The meat from heifers was assessed by the sensory panel as more tender and, when aged for 11 days, more acceptable than the meat from bulls. Older animals obtained higher scores for beef flavour intensity (P < 0.01), tenderness (P < 0.001), juiciness (P < 0.05), and overall acceptance (P < 0.001).

Thirty-nine multiparous ewes (19 Pelibuey and 20 Romanov × Pelibuey) treated with fluorogestone acetate impregnated intravaginal sponges were used to evaluate the effects of low pregnant mare serum gonadotropin (PMSG) doses and genotype on their reproductive efficiency under heat stress conditions. The sponge treatment lasted for 12 days, and 24 h before sponge removal, ewes of each genotype were injected with 140 or 280 IU of PMSG. Ewes showing estrus were naturally mated twice. Reproductive performance was not affected (P > 0.05) by the dose × genotype interaction. All treated ewes presented estrus signs within a 48-h period after sponge removal. Shorter (P < 0.05) estrus interval and higher (P < 0.05) fecundity were observed in ewes treated with 280 IU of PMSG compared to those treated with 140 IU. Pelibuey ewes exhibited shorter (P < 0.01) estrus interval and greater (P < 0.01) fertility as compared with Romanov × Pelibuey ewes. The response to estrus, gestation length, prolificacy, and percentage of single and multiple lambing were not affected (P > 0.05) by dose or genotype. In conclusion, under heat stress conditions, low PMSG doses as 140 or 280 IU can be used to successfully induce and/or synchronize the estrus in Pelibuey ewes and their crosses with Romanov, regardless of reduced fertility observed in crossed Pelibuey ewes. If a more predictable and compact estrus is required, administration of 280 IU of PMSG is recommended.

Genetic correlations between longevity and conformation traits were estimated using data on Czech Holstein cows first calved in the years 1993-2008. Longevity traits considered were length of productive life and number of lactations initiated and their functional equivalents (i.e. the longevity traits corrected for milk production). Conformation traits were twenty one linear descriptive type traits, six composite traits and height at sacrum measured in cm. A possible nonlinear relationship between conformation and longevity traits was also investigated. The heritabilities ranged from 0.05 to 0.43 for conformation traits and from 0.03 to 0.05 for longevity traits. Low to moderate genetic relationships between conformation and longevity traits were found. The genetic correlations were higher for functional longevity than for direct longevity traits. Negative genetic correlations with all longevity traits were found for height at the sacrum, stature, dairy form, body conformation, and capacity. Final score showed weak genetic correlation with all analyzed longevity traits. Positive genetic correlations occurred between feet and legs and direct longevity and functional longevity (0.19, 0.14) and between udder and direct longevity (0.10). Body condition score and angularity showed strong genetic correlations with functional longevity (body condition score 0.30, angularity -0.31). Foot and leg traits showed weak genetic correlations with longevity traits except rear legs set (side view) (-0.24) and hock quality (0.19). The udder traits showed inconsistent and rather weak genetic correlations with longevity traits, with the exception of a stronger genetic correlation between rear udder width and functional longevity (-0.22) and between central ligament and number of lactations (-0.18, -0.19). The teat traits showed always negative genetic correlations with longevity traits. The strongest correlations were found for rear teat position (-0.28) and the weakest for teat length (-0.03). Some conformation traits showed markedly stronger genetic correlations with functional longevity than with direct longevity (rear udder width and rear udder height, dairy form, body condition score, angularity, rear legs set (side view), rear legs rear view). A quadratic relationship between conformation and longevity traits did exist. Even if the linear relationship generally prevailed, the quadratic relationship should be taken into account.

Growth and survival rates (specific growth rate - SGR; survival rate - S) of Barbus barbus L. were recorded in captivity during three years from the larval period (final body weight - W = 0.2 ± 0.03 g; SGR = 13.6 ± 1.1%/day and cumulative survival - S = 76.0 ± 2.5%) to the first reproductive season (W = 62.55 ± 13.5 g; SGR = 0.89 ± 0.05%/day; S = 59.3 ± 1.5%). Final body size and SGR were compared between both sexes. Females reached the significantly higher growth rate (SGR = 0.84 ± 0.01%/day) compared to males (SGR = 0.77 ± 0.01%/day). Early puberty was observed in 17 and 32 months old males and females, respectively. Multi-stripping activity was found out in both sexes during the first reproductive season. In total, 20%, 25.8%, 30.3%, 14.6% and 9% of females were stripped once, twice and three, four and five times, respectively. But all males produced sperm during the entire reproductive season. The highest and the lowest egg production was recorded in the middle (April) and at the beginning (March) of the reproductive season (2155 ± 925 vs. 1279 ± 298 eggs per stripping). The highest and the lowest sperm production was observed at the beginning (March) and at the end (May) of the reproductive season (7.9 ± 0.08 × 10⁹ vs. 1.9 ± 0.06 × 10⁹ per stripping).

The objective of the present study was to investigate the effects of virginiamycin (VM ) supplementation on ruminal fermentation and microbial populations in steers. Four ruminally cannulated Chinese Luxi steers (BW 559.4 ± 30.1 kg) were used in a crossover design experiment with an experimental period of 28 days. The forage to concentrate ratio of the basal diet was 35:65 on dry matter basis. The experiment consisted of control treatment and treatment with control diet plus VM at a dose of 30 mg/kg concentrate (DM basis). Rumen fluid was collected at 07:30 prefeeding, at 11:30 and 17:30 postfeeding on day 27 and 28. A part of the pooled sample from rumen fluid was transferred to anaerobic culture by a roll-tube technique and analysed for species-specific real-time PCR quantification. The remaining pooled rumen fluid sample was analyzed for pH, VFA, ammonia N and l-lactic acid. The results showed that VM increased the ruminal pH (6.70 vs. 6.63; P < 0.05), but it decreased ammonia nitrogen (4.94 vs. 6.19 mg/100 ml; P < 0.01) and mean counts of amylolytic bacteria and proteolytic bacteria (P < 0.01) as compared to the control. The additive VM did not affect the l-lactic acid concentration (1.39 vs. 1.26 mmol/l) in rumen fluid. Compared to the control, the steers receiving VM have altered a trend of quantification of Selenomonas ruminantium, Anaerovibrio lipolytica, Ruminococcus albus and Streptococcus bovis in rumen fluid (0.05<p<0.1) as compared to the control. However, VM had no significant effect on Lactobacillus spp. (P = 0.41), Butyrivibrio fibrisolvens (P = 0.35), on the genus Ruminococcus (P = 0.25), Ruminococcus flavefaciens (P = 0.52), Prevotella ruminicola (P = 0.54), on the genus Prevotella (P = 0.67) and Megasphaera elsdenii (P = 0.97). In this study, we found that VM had selective effects on ruminal bacteria and influenced ruminal fermentation by changing a part of the specific ruminal bacteria populations.

The effect of supplementing dietary selenium (Se) and vitamin E was investigated in 330 24-week-old laying hens. The hens were fed a basal diet containing Se and α-tocopherol at 0.11 and 26 mg/kg, respectively, or a diet supplemented with Se at 0.3 mg/kg and vitamin E between 0 and 625 mg/kg. Se was supplied as Se-methionine or sodium selenite. The eggs were collected for analysis during the third, seventh and eleventh weeks of the experiment. Supplementation of either form of Se significantly increased the Se concentration in egg yolks and whites, with a more pronounced effect caused by Se-methionine. The egg yolk α-tocopherol concentration paralleled the dietary α-tocopherol concentration. At a high dietary α-tocopherol concentration (632 mg/kg), the retinol content in egg yolks from hens fed Se-methionine increased significantly. Supplementation of Se-methionine significantly increased the α-tocopherol content in the eggs in the third and seventh weeks of the experiment. A moderate decrease in yolk cholesterol was observed in hens fed Se-methionine and α-tocopherol at 119 mg/kg. The concentration of products from lipid peroxidation (thiobarbituric acid-reactive substances, TBARS) in egg yolks increased marginally during the refrigerated storage of the eggs for 2 weeks. The effect of dietary vitamin E on TBARS formation was generally small, although a more significant effect was observed at the highest dose tested.

The objective of this research was to examine heritabilities and genetic, phenotypic and permanent environmental relationships between milk dry matter (DM) and milk traits such as milk, fat, protein and lactose yields, milk urea nitrogen (MUN) and somatic cell score (SCS) in extended (to 395 days) lactations of Holstein cows from a big farm in Poland. The data set consisted of 78 059 test day records from the first, second and third lactations of 3 792 cows, daughters of 210 sires and 1 677 dams. Single- or two-trait random regression models were used with fixed effects of calving year, calving month, dry period and calving interval and random additive genetic and permanent environmental effects. The last two fixed effects were not included in the analysis of first lactation data. The highest values of heritabilities for all traits, except DM, were observed in the second lactation. First lactation heritabilities for all traits - except milk yield and SCS - were smaller than those in the third lactation. Lactose yield was highly heritable, with average h² equal to 0.25, 0.29 and 0.28 in lactations 1, 2 and 3, respectively. Heritability for DM was slightly lower than that for lactose (0.22, 0.26 and 0.28 for lactations 1, 2 and 3, respectively). In all lactations heritabilities for SCS were below 0.1. Genetic correlations between DM and milk yield (0.64-0.74) were lower than those between MUN and milk yield (0.67-0.79) as well as between lactose and milk yield (0.72-0.82). In general, DM was much more closely correlated with fat or protein yield (0.55-0.79) than with MUN or lactose (0.38-0.76). Only in the third lactation the correlation between DM and protein (0.72) was lower than between lactose and protein (0.76). For all lactations there were very high genetic correlations between DM and lactose (0.96-0.98) and high correlations between DM and MUN (0.63-0.83) and between lactose and MUN (0.70-0.85). The results suggest that further research is needed, focused on DM and its relationship with other traits in larger populations.

The aim of this study was to continuously monitor ruminal pH and redox potential of individual dry cows using a newly developed wireless device. Three dry Holstein cows fitted with rumen cannulas were used for the individual measurement of ruminal pH and redox potential (Eh) using a newly developed wireless device. The experiment was carried out in the period of 14 days consisting of a 10-day preliminary period followed by a 4-day measurement period. Cows were fed twice daily the diet based on maize silage, lucerne hay and concentrate. During the measurement period ruminal pH and redox potential were monitored continuously using a developed wireless probe. Average daily feed intake throughout the experiment was 8.2 kg/day. The mean ruminal pH was almost identical in Cows 21 and 25, being 6.79 and 6.75, respectively, and was lower than in Cow 26 (6.86; P < 0.05). The mean Eh of the ruminal fluid was -274 mV in Cow 21 and 26 and -270 mV in Cow 25, while the results did not differ significantly (P > 0.05). The diurnal pattern of ruminal pH and Eh showed a similar trend in all animals. Mean values of rH (Clark's exponent) calculated for Cows 21 and 25 being 4.43 and 4.48, respectively, were lower than the value calculated for Cow 26 (4.59; P < 0.05). This method may be useful for investigating factors affecting the dynamics of ruminal fermentation and may also help in the identification of variables associated with various metabolic disorders.

An experiment was conducted to investigate the effects of dihydropyridine supplementation on growth performance and lipid metabolism of broilers. A total of 480 one-day-old female Arbor Acres broiler chicks were randomly divided into four groups, each group had six replications of 20 birds. Each group was fed a maize-soybean meal diet supplemented with 0, 100, 200, 300 mg/kg dihydropyridine, respectively, for six weeks. At 42 days of age, body weight and feed intake were not affected by dihydropyridine, while feed efficiency was significantly increased by 8.4%, 15.0% and 12.0%, respectively (P < 0.05). The percentage of abdominal fat and the percentage of liver fat were reduced by 24.5%, 25.9%, 23.3%, and 23.6%, 26.7%, 26.0%, respectively (P < 0.05). The higher level of dietary dihydropyridine (200 or 300 mg/kg) increased the hormone-sensitive triglyceride lipase activity in liver and abdominal fat (P < 0.05). The lipoprotein lipase activity in abdominal fat was significantly decreased by dihydropyridine (P < 0.05). The activity of glucose-6-phosphate dehydrogenase and malic dehydrogenase in liver was significantly reduced, whereas the isocitrate dehydrogenase activity in liver was not affected by dietary dihydropyridine. The content of cAMP was significantly increased by dihydropyridine, but malondialdehyde content was decreased (P < 0.05). Dihydropyridine at doses of 100 and 200 mg/kg increased apolipoprotein B (P < 0.05), but 300 mg/kg dihydropyridine had no effect on apolipoprotein B compared with the control group. Triiodothyronine was significantly increased by dietary dihydropyridine (P < 0.05). There were no differences in apolipoprotein A, cholesterol, trigly-cerides, high density lipoprotein-cholesterol, very low density lipoprotein-cholesterol, thyroxine and insulin among dietary treatments. It is concluded that supplementing dihydropyridine has a beneficial effect on feed efficiency and lipid metabolism of broilers, and that 200 mg/kg dihydropyridine supplementation is the optimum dose.

The relationships between conformation and longevity traits were analysed in 58 493 Czech Fleckvieh cows first calved from 1994 to 2003. All cows were scored for conformation during the first lactation. Genetic correlations between longevity and conformation traits were estimated by bivariate runs using the VCE 4.0 program for variance component estimation. The values of heritability for conformation traits were in the range from 0.06 to 0.63 and for longevity traits from 0.04 to 0.05. Low or intermediate genetic relationships between recorded linear traits and longevity trait were found. The correlations were lower for functional longevity. Body measurements showed negative genetic correlations with real as well as functional longevity (-0.12 to -0.29). The dairy character negatively correlated with longevity traits (-0.18 to -0.26). The muscularity and udder showed a zero correlation with functional longevity, while the feet and legs were not correlated with real longevity. The highest positive genetic correlations between real longevity and objectively scored linear type traits were found for hock (0.24), rear udder attachment (0.28), fore udder length (0.16) and central ligament (0.11). On the contrary, the correlation between the udder depth and the milk-corrected longevity was positive (0.28) and higher than in the case of real longevity.

The breeding value (EBV) of Holstein cattle milk performance from the first lactation was evaluated using a regular Animal Model or by Single-Step Prediction of the genomic breeding value (GEBV). A total of 838 bulls were genotyped using the Illumina BovineSNP50 Beadchip V2. Two overlapping sets of milk performances were evaluated: calving years 1991-2004, with 729 341 lactations and 1 394 487 animals in the pedigree and calving years 1996-2009, with 808 436 lactations and 1 487 608 animals in the pedigree. The older data set included 526 genotyped bulls, in which the daughters' milk performance was known for 210 individuals. All of the genotyped animals were included in the newer data set. Of the young genotyped bulls from the older set, 279 had more than 50 daughters with performance records in the newer set. Genomic relationship matrices (G) were constructed from the allele frequencies of the current genotyped population or by assuming a constant value of 0.5 for all loci. Using current allele frequencies, the correlation of G with the pedigree relationship (A) was 0.74, while it was 0.77 when the constant value was used. G was blended with A with weights of 80 or 99%. The average EBV of the genotyped bulls exceeded the mean EBV of the entire population by 3 SD. Although the number of reference bulls was small, genotyping resulted in an increase of approximately 0.05 in the correlation of the GEBV of young bulls with their results after progeny testing. Only small differences in correlations were found in dependency on the methods used for the determination of G and in dependency on the weight used in blending G with A. Both EBV and GEBV in the older set showed higher correlations with the GEBV of the newer set than the EBV of the newer set.

The indicators of follicle development with regard to the growth wave order, the first ovulation, animal parity, and also with regard to the simultaneous presence or absence of a follicular cyst were determined in cows in the course of 60 days postpartum. Follicular dynamics were monitored daily by ultrasonography. The animals were assigned to three groups based on the time of the 1^st ovulation: G1 (n = 9) - the 1^st dominant follicle (DF) ovulated, G2 (n = 10) - ovulation occurred on the 2^nd or later follicular waves, and G3 (n = 5) - no ovulation occurred during the experimental period. G1 animals showed better fertility later (no cyst, less days open, P = 0.07, less hormonal treatment, P = 0.008). The rhythm of follicular wave development was generally similar in all the animals (based on emergence of the first follicular wave, the interval from emergence to deviation, and the number of all follicular waves). Nevertheless, emergence of follicular waves and deviation occurred by 0.5-0.9 day earlier in primiparous than in multiparous cows and in G1 vs. G2, or G3, respectively (in all P < 0.05). DF development was independent of parity as well as group effects, but the maximum size and growth rate (1.2 vs. 0.8 cm/day, P < 0.05) were higher in ovulatory follicles (OF) than in regressive ones (rDF). The presence of a growing cyst decreased the probability of rDF as well as OF development (P < 0.0001). The OF growth rate was faster in the milieu of a stagnating cyst than without any cyst (P < 0.04). Therefore, the development of follicles was dramatically suppressed beyond, but nor before, deviation in the milieu of a growing cyst. Cessation of the cyst growth accelerated the development of OFs. On the contrary, a cystic structure without any significant growth can persist for weeks with no effect on successful follicular development.