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This study explored the regulatory effect of temperature stress on fatty acid biosynthesis in the early stage of common carp (Cyprinus carpio) based on Δ6-fatty acids desaturase (Δ6FAD) and elongase-5 (ELOVL5) gene expression and fatty acid composition. One-day-old carp larvae were selected, and after seven days of acclimatisation at 25 °C, the larvae were subjected to temperature stress for 96 h in water at 32 °C or 10 °C. In the post-larval stage, 30-day-old carp juveniles were selected and, after seven days of acclimatisation at 25 °C, were subjected to temperature stress for seven days in water at 32 °C or 10 °C. The results showed that common carp larvae could rapidly and highly express Δ6FAD and ELOVL5 genes within 48 h at high temperature (32 °C) compared with the 0 h group (P < 0.05), while gene expression began to gradually increase after 48 h at low temperature (10 °C). There was a significant improvement in C22:6n-3 and C20:5n-3 after 96 h at low temperature compared with the 0 h group (P < 0.05). In common carp juveniles, the Δ6FAD gene in the intestine, brain and liver was sensitive to low temperature, but the ELOVL5 gene in the intestine, brain and liver of common carp was sensitive to high temperature. The low temperature increased the amount of highly unsaturated fatty acids (HUFA) in the common carp juveniles. The results indicated that temperature could regulate the expression of the Δ6FAD and ELOVL5 genes for HUFA production, as well as for participation in the biosynthesis of fatty acids in the body during the early development of common carp. The results of this study help clarify the regulatory effects of temperature on fatty acid biosynthesis during the early development of common carp.

Indigenous chickens play a significant role in food security, income growth and socio-cultural life of rural households in Vietnam. This study was conducted to assess the genetic diversity as well as the phylogenetic relationships of Vietnamese indigenous chickens (Gallus gallus) to support the conservation of their genetic resources for sustainable rural farming.  In this study, the genetic diversity and the phylogenetic relationships of 10 Vietnamese indigenous chicken breeds were analyzed using complete sequences of mitochondrial DNA (mtDNA) displacement-loop (D-loop) region. The average nucleotide and haplotype diversities of Vietnamese chickens were 0.006 3 ± 0.000 22 and 0.918 ± 0.010, respectively. A total of 39 polymorphic sites and 29 haplotypes were identified. The maximum likelihood tree classified these haplotypes into seven haplogroups (A, B, C, D, E, G and V), with haplogroups A and B being the two predominant maternal lineages of Vietnamese indigenous chickens, while haplogroups C, D, E, G and V were found in the remaining chickens. Several haplotypes from different haplogroups were shared among some chicken breeds. These results suggested that Vietnamese indigenous chicken breeds have multiple maternal origins, mainly from Chinese, Southeast Asian and Indian chickens, and that these breeds share common maternal lineages. The high level of genetic diversity in Vietnamese chickens demonstrates significance of conservation for future use.

The present study aimed to determine the incidence and coincidence of white striping (WS), woody breast (WB) and spaghetti meat (SM) in raw chicken breast meat (n = 300) collected 3–3.5 h post mortem from commercial broiler flocks (Ross 708 males, 56 days of age). The fillets were scored for the occurrence and severity of WS, WB and SM using visual and tactile methods, and the relationship between myopathies and breast weight was evaluated. A total of 88% of samples (out of 300) had either one or a combination of three myopathies, leaving only 12% without any myopathies. Approximately 29% of the fillets had only one myopathy present, with 59% of the samples demonstrating the cooccurrence of breast myopathies. In the present study, 47.7% of WB samples also exhibited WS, while the cooccurrence of WB and SM was exhibited in 14.7%. Based on binomial logistic regression, an increase in WB scores decreases the odds that the fillet may be affected by SM myopathy. No association was found between SM and fillet weight. Multinomial logistic regression showed that the weight of breast fillets was positively associated with WB1 (P = 0.011), WB2 (P < 0.001), and WB3 (P < 0.001). Furthermore, positive associations were found between WS1 and WB3 (P = 0.004) as well as between WS2 and WB3 (P < 0.001). The percentage distribution changes of each WB and WS myopathy score were used in relation to the 10 weight groups. The percentages of WB3 increased and WB0 decreased as the average fillet weight increased. Regarding linear regression, these results exhibited a positive linear relationship for both WB (R² = 0.91, P < 0.001) and WS (R² = 0.71, P = 0.002) myopathy with fillet weight. A high prevalence of myopathies was observed. The incidence of severe WB categories and the overall high cooccurrence rate are alarming.

20α-hydroxysteroid dehydrogenase (20α-HSD) is a member of the aldo-keto reductase family. These enzymes play a pivotal role in regulating steroid hormones, such as androgens, oestrogen, and progesterone, and are, therefore, considered vital targets for determining whether a pregnancy is maintained. In this study, we investigated the association between 20α-HSD and apoptosis-related genes in luteal tissues (at 30, 60, and 90 days of gestation) and cells from early gestation in cattle. The corpus luteum altered the number of large lutein cells from 30–90 days. The change in the junction of the connective tissue appeared to affect the density of the corpus luteum. In addition, 20α-HSD was detected in the corpus luteum and cultured cells during early pregnancy, in contrast to the results of previous studies. The overall expression pattern of the 20α-HSD and Casp-3 proteins was lower on day 50 of gestation than on days 30 and 90. However, the 20α-HSD expression gradually increased from 30 to 90 days of gestation. When the 20α-HSD protein was increased to 0.5 μg/ml, 1 μg/ml, and 1.5 μg/ml in the luteal cells collected on day 30 of pregnancy, apoptosis was analysed after 48 hours. 20α-HSD generated in the cells was confirmed, and the concentration gradually decreased as the concentration increased. However, the expression of Casp-3 showed an overall similar expression pattern. Notably, the 20α-HSD and Casp-3 proteins were lowest at 1.5 μg/ml supplemented with 20α-HSD, with higher levels in the cytosol than in the cytoplasm. These results suggest that 20α-HSD plays a role in maintaining normal pregnancy, particularly by regulating the progesterone concentrations during luteal cell development.

This study is to explore the effects of natural tannin (NBT) on intestinal injury in piglets challenged with enterotoxigenic Escherichia coli (ETEC). Thirty-two 7-day-old piglets were divided into four groups: I) control group, piglets were fed a basic diet without challenge; II) ETEC group, piglets were fed a basic diet and challenged with enterotoxigenic E. coli; III) NBT + ETEC group, piglets were fed a basic diet with supplementation of 2 g/kg NBT and challenged with enterotoxigenic E. coli; and IV) ZnO + ETEC group, piglets were fed a basic diet with supplementation of 3 g/kg ZnO and challenged with enterotoxigenic E. coli. Results showed that diarrhoea rate was significantly increased in ETEC group, whereas it was decreased after NBT supplementation (P < 0.05); NBT supplementation significantly increased the average daily gain of ETEC-infected piglets. ETEC group showed damaged intestinal morphology (as indicated by decreased villus height, surface area and increased crypt depth) and barrier function (as indicated by decreased d-xylose content and increased diamine oxidase activity), induced oxidative stress (as indicated by increased myeloperoxidase activity) while supplementation of NBT had an obvious impact on the recovery of intestinal function and alleviated the oxidative damage. Further analysis showed that NBT could decrease the expression of genes related to intestinal injury (matrix metalloproteinase-3), and specifically upregulate the expression of oxidative stress-related genes (nuclear factor erythroid 2-related factor 2 and hypoxia inducible factor-1). Overall, dietary supplementation of NBT relieved intestinal injury and oxidative stress in piglets challenged with ETEC. NBT could be an alternative to ZnO as a feed additive in piglet diet.

This study aimed to determine the potential of Wallachian sheep in quantitative and qualitative indicators of milk production under extensive conditions of the Western Beskids mountains. Milk samples were collected from the group of 38 non-dairying sheep selected from the basic 120-head flock. Ewes were monitored during four control days (from 27^th April, the average 42^nd day of lactation to 4^th August, the average 142^nd day of lactation) to cover the whole lactation period. Ewes were investigated for their milk production and for milk quantity parameter. Milk quality indicators included percentage estimation of milk components (fat, protein, casein, lactose, dry matter), somatic cell count (10³ cells/ml), vitamin A and E content (mg/kg), and K, Mg, Ca, Zn, Cu (mg/kg) content. Milk production ranged from 1 017.37 g (early stage of lactation) to 416.87 g (late stage of lactation period). The milk contained high fat (6.06–8.44%) and protein (4.68–5.68%) percentages, low somatic cell count and favourable distribution of minerals and vitamins. In general, results of this study indicate a possibility for low-productive traditional grazing system with extensive sheep breeds not only for cultivating the area but also for the purpose of high nutritional food with beneficial aspect on human health.

In general, it can be stated that the economics of non-dairy sheep breeding in the Czech Republic experienced a worsening trend in recent years. One of the ways to improve this situation is to use some of these breeds also for milk production. One of the possible breeds usable for milk production, especially for the good milk production of mothers, is the Clun Forest (CF). The aim of our experiment was to evaluate the daily milk yield (DMY) and the contents of fat (F), total protein (TP) and lactose (L), pH, titratable acidity (TA), concentration of urea (CU) and somatic cell count (SCC) in CF ewes during lactation. In our experiment, the following means of individual traits for the whole lactation were found: DMY: 579 g, contents of F, TP and L: 6.73%, 5.82% and 4.98%, pH: 6.55, TA: 8.74 °SH, CU: 36.08 mg/100 ml and log SCC: 4.71. The stage of lactation had a significant (P < 0.01) effect on DMY, contents of F and TP and pH and TA. The results of our experiment show that CF ewes had lower DMY than dairy breeds (DB). However, the majority of the milk quality traits was comparable to DB. Moreover, the high fat and protein contents and the values of most other milk quality traits are good prerequisites for high cheese yield and optimal final quality of other sheep’s milk products. The results of our experiment suggest that CF ewes could be used for milk production while the milk production of CF ewes should ensure an improvement in the economics and competitiveness of smaller farms in particular.

Lipid-rich bovine serum albumin (LR-BSA) has been reported to increase the survival rate of blastocysts after freezing and thawing. However studies on the early development of in vitro fertilised (IVF) embryos are still insufficient in cattle. This study investigated the blastocyst productivity of in vitro culture (IVC) medium (synthetic oviductal fluid medium with amino acids, mSOFaa) supplemented with 5% fetal bovine serum (FBS, Control) or LR-BSA (1, 2.5, 5 mg/ml dosages, respectively) and the qualitative characteristics of produced blastocysts. Cleavage rates on day 2 were similar between all groups. Significant differences were obtained in the blastocyst rate in the 2.5LR-BSA group compared with the control (23.5% vs 35.7%, P < 0.05). Hatching rates were significantly higher in all treatment groups than in control (P < 0.05). The cell number in blastocysts did not differ among groups, but the apoptotic index in the 5.0LR-BSA group was higher than the control (P < 0.05). The expression of embryo quality-related markers was affected. Octamer-binding transcription factor 4 (Oct4), placenta associated 8 (Plac8), and sex-determining region Y-box 2 (Sox2) genes expression in the 2.5LR-BSA group were significantly up-regulated compared to the control (P < 0.05). Cytoplasmic lipid contents and the lipid droplet formation-related gene, sterol regulatory element binding transcription factor 1 (Srebf1), were significantly increased in the 5.0LR-BSA group (P < 0.05). Therefore, the LR-BSA supplementation (2.5 mg/ml) to mSOFaa medium could contribute to the early development of bovine IVF embryos and the qualitative improvement of the resulting blastocysts.

This study was conducted to determine the individual types of crystallisation structures of cervical mucus (arborisation phenomenon) in sheep and changes in the types of these structures during oestrus. A total of 80 ewes aged between two and eight years were included in the study. Oestrus synchronisation was performed using intravaginal sponges, and samples of cervical mucus were collected 55–57 h after the removal of intravaginal sponges and subsequently evaluated. The crystallisation structures of the cervical mucus of sheep exhibit the same sequence during oestrus as in cattle. The most frequently occurring types of crystallisation in the observed sheep included twig-shaped (33.33%), twig-shaped-clubmosses (24.00%) and clubmosses (14.67%). The least common type was fern frond crystallisation (1.33%). A statistically significant difference was found between the representation of individual types of crystallisation (P < 0.01). As with cattle, it is possible to use the evaluation of the crystallisation of cervical mucus to determine the optimum time for insemination, especially in groups of animals with previous synchronisation/induction of oestrus. Establishing the correct time for insemination or natural mating with a ram makes it possible to optimise breeding management and improve pregnancy rates, which are crucial in breeding these seasonally polyoestrous animals. Based on the results, it can be stated that insemination should take place 57+ h after the removal of intravaginal sponges and the application of hormonal treatments for oestrus induction and synchronisation (equine chorionic gonadotropin).

Despite the routine use of cryopreservation in dairy cattle, the subsequent deterioration in the quality of bull insemination doses (IDs) is an incentive to refine cryopreservation protocols, including the composition of the ID. The aim of this study was to examine, using a flow cytometry assay, whether the selected concentrations of low density lipoproteins (LDLs) extracted from hen-egg yolk may improve the post-thaw quality of the ID diluted with a plant-based extender. In total, 30 ejaculates from five sires (six trials per animal) were collected and processed at the Artificial Insemination Centre. The effect of the low density lipoprotein supplementation to the AndroMed^® diluent at 4 and 8% (v/v) on the cryopreservation efficiency was tested. The effects of the modified extenders were determined on different sperm subpopulations by simultaneous quadruple staining for flow cytometry as the percentage of sperm with intact plasma membrane and acrosome (PMAI), PMAI sperm showing high mitochondrial membrane potential (HMMP), sperm with plasma membrane damage (PMD), and sperm with acrosome damage (AD). It was observed that the 8% LDL treatment was more effective (P < 0.05) in preserving all the analysed parameters than AndroMed^® without any supplementation. The supplementation of the AndroMed^® extender with 8% LDL resulted in the most optimal values of the PMAI (30.61 ± 1.13), HMMP (68.81 ± 1.25), PMD (68.69 ± 1.14), and AD (38.36 ± 1.13) compared to the control treatment (24.86 ± 1.13 for PMAI, 47.79 ± 1.25 for HMMP, 74.77 ± 1.14 for PMD, and 42.83 ± 1.13 for AD. The results of the study also demonstrated a synergistic positive effect of the LDL and soybean lecithin-based diluent on the spermatozoa post-thaw quality and resilience, based on 2 h long incubation. In conclusion, the soybean based semen extender treatment with LDL represents a beneficial tool to mitigate the detrimental effect of cryopreservation.

A 4 × 2 factorial experiment was conducted to investigate the effect of dietary supplementation levels (0, 5 and 10 g/kg) of chamomile flower powder and a level (60 mg/kg) of salinomycin on performance and gut health of broiler chickens under coccidiosis challenge. A total of 320-day-old Ross 308 broilers were assigned to eight treatments of four replicates with 10 birds. Oral inoculation of the challenged groups with Eimeria tenella occurred on day 8. On day 10, disease challenge and additive level significantly (P = 0.003) interacted, decreasing the feed intake. Feed intake significantly (P ≤ 0.001) decreased in birds supplemented with 10 g/kg of chamomile. At 35 days, birds fed chamomile and anticoccidial significantly (P = 0.001) increased body weight (BW) and weight gain (WG). Disease challenge adversely influenced (P = 0.001) BW and WG. Additive level and disease challenge significantly (P = 0.001) interacted on feed conversion ratio (FCR). Anticoccidial and chamomile improved (P = 0.001) FCR of birds regardless of the rearing conditions. Significantly (P = 0.001) better FCR was observed in the unchallenged birds. The interaction of experimental factors was significant (P ≤ 0.04) on the relative weight of bursa. Disease challenge significantly (P = 0.005) increased the relative weight of liver whereas that of bursa decreased. Cholesterol (P = 0.002), albumin/globulin (P = 0.009), aspartate aminotransferase (AST) (P = 0.002) and alanine transaminase (ALT) (P = 0.001) significantly increased in challenged birds. The interaction of experimental factors was significant (P = 0.002) on villus length, crypt depth and villus height/crypt depth ratio (P = 0.001). Longer (P = 0.001) villi were found in anticoccidial and chamomile supplemented birds. Coccidiosis adversely (P = 0.001) influenced the jejunum morphology. Crypt depth decreased and villus height/crypt depth increased in chamomile offered birds (P = 0.001) regardless of the challenge conditions. Bursal morphology was significantly influenced by experimental factors. Dietary supplementation of chamomile had positive effects on broiler performance, immunity and intestinal morphology during exposure to the E. tenella parasite. Chamomile could be used as a potential natural anticoccidial in broiler nutrition.

Feed additives belong to a number of climate change mitigation strategies being sought to reduce methane emissions in ruminants. In this study, the effect of biochar or biochar and urea supplementation on dairy cow performance and methane production was assessed. Eighteen cows were used in a 3 × 3 latin square design with three feeding groups: control with no supplementation (CO), biochar supplementation (BC, 200 g/day) and biochar and urea supplementation (BC + U, 200 g/day biochar and 90 g/day urea). All cows were fed a forage mixture ad libitum and 5 kg of concentrates per day on average. Methane emissions were measured in respiration chambers. Biochar as well as biochar and urea supplementation did not affect total dry matter, energy and utilisable protein intake. However, lignin intake was higher in the BC group and crude protein intake was higher in the BC + U group compared to the CO group. Supplementation of feed additives did not affect milk production and milk composition, except for the higher milk urea content in the BC + U group. Feed conversion, diet digestibility and methane production were not affected by feeding strategy. In conclusion, biochar supplementation does not reduce methane emissions, but it does not negatively affect dairy cow performance.

The aim of this study was to estimate the effects of crossbreeding on milk production and milk components in crossbred Tsigai, Lacaune, and Improved Wallachian sheep used to create a synthetic Slovak dairy sheep population. The local breeds Tsigai and Improved Wallachian were crossed with the high-yielding breed Lacaune to increase milk yield. The effects of crossbreeding were evaluated based on breed and heterosis effects. The database used consisted of 23 018 lactations from 15 888 ewes. The effects of crossbreeding on milk production and fat and protein content were estimated using the restricted maximum likelihood method in REMLF90. Fixed effects on milk yield were also studied. In ewes with a 100% heterosis effect (ewes from purebred parents of different breeds), the heterosis effect increased milk production by 11.642 kg, milk fat production by 0.772 kg, and protein production by 0.565 kg per milking period. The effect of the Tsigai breed on milk production was –21.98 kg compared to Lacaune, while for the Improved Wallachian breed, the value was –38.58 kg. The Tsigai direct breed effect reduced fat production by 1.56 kg and protein production by 1.34 kg. The Improved Wallachian direct breed effect was –2.71 kg for fat production and –2.27 kg for protein production.

The black soldier fly (Hermetia illucens) serves as an alternative source of protein in poultry production. However, there is little available information on feeding live black soldier fly larvae (LBSFL) to hens. The present study filled this gap by testing the effect of dietary LBSFL on laying hen performance, feed economy, egg quality, and yolk fatty acid composition. In total, one hundred forty-four 25-week-old Charoen Pokphand Brown laying hens were assigned to four groups. Experimental birds were provided a basal diet supplemented with 0.0 (T1), 10.0 (T2), 20.0 (T3), or 30.0 (T4) g/kg LBSFL. Our results indicated that no effects on body weight gain, egg yield, egg weight, or egg mass (P > 0.05) were observed in any of the dietary LBSFL groups. The addition of 10.0 g/kg LBSFL decreased feed intake, feed conversion ratio, and feed cost (P < 0.05), contrary to two higher doses of LBSFL. Similarly, the egg quality parameters were not influenced (P > 0.05) by the dietary LBSFL except for the egg yolk colour which significantly decreased with increasing LBSFL levels. Furthermore, the values for lightness (L*), redness (a*), and yellowness (b*) of the egg yolk were different (P < 0.05) between the four treatments. Paler egg yolk was found in the 20.0 and 30.0 g/kg LBSFL groups compared to the control group (P < 0.05). Significantly lower deposition of C18:3n6 was found for 30.0 g/kg, whereas there was a significant decrease in deposition of C22:6n3 with all LBSFL groups (P < 0.05). C20:3n6 levels, on the other hand, increased significantly in the 20.0 g/kg LBSFL group (P < 0.05). Thus, feeding LBSFL has no potential to increase the proportion of anti-inflammatory n-3 fatty acids. From an economic point of view, it is advantageous to feed the hens a dose of 10 g/kg LBSFL.

This experiment aimed to study the effect of Broussonetia papyrifera leaf meal (BP) on the growth performance, antioxidant capacity, intestinal permeability, and caecal microbiota of growing rabbits. A total of 240 weaned Ira male rabbits were randomly divided into four groups with six replicates of 10 rabbits each. The BP was added at 0% (CON), 3.0% (BP3), 6.0% (BP6), and 9.0% (BP9). All diets were isoenergetic, isonitrogenous, and isofibrous. The feeding trial lasted for 28 days. The results showed that adding BP had no significant effect on the growth performance of rabbits. Compared with the CON group, groups BP6 and BP9 showed the reduced serum diamine oxidase content (P < 0.01). The jejunal secretory immunoglobulin A content in BP6 was higher than in the CON group (P < 0.01). The addition of BP had no significant effect on the jejunal antioxidant capacity. The BP9 increased the abundance of the caecal Firmicutes; BP3 and BP6 increased Bacteroidota; BP6 and BP9 increased Proteobacteria (P < 0.05). It is concluded that the BP can be used as a roughage source to reduce intestinal toxic markers, improve the intestinal immune function and the abundance of caecal microflora in growing rabbits.

Insects like housefly (Musca domestica L.) are future feed resources for economic animals because insects can improve growth performance by promoting the immune function and gut microbial balance. However, little is known about research reports on housefly larvae extracts containing an antibacterial peptide. This study investigated the effect of feeding diets supplemented with housefly larvae extract (HLE) containing antibacterial peptides on the growth performance of broiler chickens. Nine hundred broilers (Ross 308) were fed diets containing HLE for 35 days. Treatment groups consisted of CON (control without HLE), PC (positive control, 8 ppm of avilamycin), HLE50 (diet containing 50 ppm of HLE), HLE100 (diet containing 100 ppm of HLE), HLE150 (diet containing 150 ppm of HLE), and HLE200 (diet containing 200 ppm of HLE). Body weight gain and feed conversion ratio were significantly (P < 0.05) increased in HLE150 and HLE200 groups compared to those in the CON group. Spleen weights were higher in HLE150 and HLE200 groups than in the CON group. Caecal bifidobacteria and Lactobacillus counts were significantly (P < 0.05) higher in HLE150 and HLE200 groups whereas E. coli and coliform bacteria counts were higher in the CON group. Caecal acetic acid, propionic acid, and total short-chain fatty acid levels were significantly (P < 0.05) higher in HLE150 and HLE200 groups than in the CON group. These results show that feeding diets containing 150 ppm of HLE containing antimicrobial peptides could replace antibiotics to improve the growth performance of broiler chickens.

This study was conducted to investigate the effects of protease supplementation on the behaviour, slaughter performance, meat quality, and immune organ indices of broilers. A total of 240 one-day-old Arbor Acres broiler chickens were randomly allocated to four treatments, with six replicates per treatment and 10 broilers per replicate. Chickens were fed corn-soybean meal basal diets supplemented with 0, 4, 8, and 12 IU/g of protease. Compared with 0 IU/g of protease supplementation, 12 IU/g of protease increased the average and minimum time of feeding and drinking behaviour (P < 0.05); increased the average, maximum, and minimum time of preening behaviour (P < 0.05); and decreased feeding, walking, and stretching frequency (P < 0.05). pH_24h of breast and thigh muscles had improved (P < 0.05). The shear force of the breast muscle and the cooking loss of the thigh muscle had decreased (P < 0.05). Compared with 0 IU/g of protease, 4 IU/g of protease increased the average and minimum time of lying behaviour (P < 0.05) and decreased stretching, scratching, and aggressive frequency (P < 0.05). The shear force of the thigh muscle and spleen index had enhanced (P < 0.05). Protease can be used as an additive in a broiler diet for production.

This research paper addresses the hypothesis that the peptidoglycan recognition protein 1 (PGLYRP1) gene polymorphism (Tyr76His; dbSNP ID: ss104796364) has an influence on some performance traits and causes of culling in Polish Holstein-Friesian red-white cows. The study involved 134 cows kept on a farm in the south-west of Poland. PGLYRP1 genotypes TT, CT, and CC were detected. It was shown that compared with cows with genotypes CT and TT, the individuals with genotype CC were characterised by higher lifetime yields and higher amounts of lactation milk, fat, and protein. A beneficial effect of genotype CC, compared with genotype TT, was also noted in the case of the lifespan and, consequently, the length of the productive life and the average number of lactations. Diseases of the musculoskeletal system (genotypes CC and TT) and disorders of the reproductive system (genotype CT) were the most common causes of culling. An essential practical observation was the potentially higher susceptibility of cows with genotype CC to mastitis, which resulted in the necessity to cull over one-fifth of the animals in this group. Simultaneously, no cows in this group were culled due to low performance or metabolic, gastrointestinal, and respiratory diseases. Therefore, the PGLYRP1 gene seems to be a promising potential herd health marker; however, to consider it the main gene, it is necessary to extend the investigations to include more individuals and other breeds of dairy cattle.

The aim of this study was to improve the understanding of the contribution of components typically found in milk, but which are not often included in analyses, to the nutritional status of dairy cows. This was undertaken by analysing the amount and composition of milk produced by Simmental dairy cows, a dual-purpose breed farmed in the Czech Republic. Apart from the more frequently analysed group of components in milk, a less frequently analysed group of components were also investigated. This group, typically, consists of the following components: urea, casein, citric acid, beta hydroxy butyrate (BHB) ketones and free fatty acids. The average content of urea, casein and citric acid in milk is 25.75 mg/100 ml, 2.96%, 0.15%, respectively. The influence of environmental factors on these indicators was evaluated, as well as the degree of hereditary establishment. These less frequently analysed components (indicators), as well as the more frequently analysed components of milk, are subject to several external influences, especially the influence of the breeder, the year and the season of calving. The content of these components varied significantly statistically during the lactation period and also in the order of lactation. The influence of a cow’s individuality and the degree of additive genetic background are evident, with estimated heritability coefficients ranging from 0.04 for the BHB ketone content to higher values, e.g., 0.28 for citric acid or 0.31 for the lactose content in milk. The relationships between the components of milk and the daily milk yield were also evaluated, and statistically significant negative correlations were found between the content of casein and the daily milk yield (–0.47) and between the lactose content and the number of somatic cells (–0.37).

The aim of this study was to evaluate the effect of rumination time, eating time and season on milk yield and on milk component content in the context of milk recording. The experiment was carried out with two breeds – Czech Fleckvieh cattle and Holstein cattle – for one year. Vitalimetr 5P neck responders were used to monitor eating and rumination time. For statistical evaluation, the time of eating and rumination was divided into three groups according to the length of eating and ruminating, with each breed being categorised separately. The highest protein content, which was 3.6%, was calculated for the group with an average eating time. The fat content was highest for the group with a below-average eating time. On the other hand, the highest milk yield was statistically significantly (P < 0.01) higher in the group with the longest eating time. In terms of rumination, the trend was similar to that of the eating period. In the evaluation of the effect of rumination time, there was no difference in protein %, fat kg and fat % content. A significant (P < 0.05) increase of protein kg was observed with higher rumination time. Changes in milk yield and milk components also occurred throughout the year. During the winter months, the yield decreased, but there was an increase in milk constituent content. During the summer months, the reverse results were obtained. The findings of this study highlight the importance of evaluating eating and rumination time as a potential predictor of milk yield and milk solids content, which are important in milk monetization.

The aims of this study were to examine bacterial communities in relation to the rumen digestion of rice straw and to understand how concentrate supplements affect gut bacteria involving the digestion of a rice straw-based diet. The substrates were rice straw (RS) alone (experiment 1) and RS with 25% concentrates (barley and kidney beans) (experiment 2). The genomic DNA was collected to determine bacterial diversity by conducting denaturing gradient gel electrophoresis (DGGE). V6–V8 region group-specific (Clostridium and Bacteroides) primers were employed in the analyses. The DGGE band pattern was subjected to cluster analysis to demonstrate the similarity and difference between dietary treatments and solid-liquid fractions. Fibre digestibility, gas production, and volatile fatty acid (VFA) concentration were increased with incubation time. The differences between solid and liquid fractions were great in total bacteria, Clostridium, and Bacteroides communities. Clostridium and Bacteroides communities appeared unaffected by incubation time, whereas great differences existed between solid and liquid fractions throughout incubations (experiment 1). Barley and kidney bean supplements increased gas production and lowered rumen fluid pH, whereas changes in VFA concentration were significant only for kidney bean supplement. The Clostridium, and Bacteroides groups were affected by barley and kidney beans in the liquid fraction. However, the solid fraction was stable (experiment 2). These results indicate a rigid and stable community structure of Clostridium and Bacteroides groups involved in the digestion of rice straw-based diets in the rumen. Distinctive differences between solid and liquid fractions were described; hence, separate analyses of two fractions may greatly help understand the relationship between fermentation patterns and microbial communities in the rumen.

The aim of this study was to monitor the occurrence of abnormal eggs in five initial laying lines of the domestic chicken (Gallus domesticus) between 2017 and 2021. The incidence of abnormal eggs, cracks, shell-less eggs, and double-yolk eggs were examined as part of the monitoring. Also assessed was the laying intensity, which ranged from 83.7% for the Barred Plymouth Rock (BPR) B line to 96.8% for the Rhode Island Red (RIR) A line. A statistically significant relationship between the line and control year was discovered for all varieties of abnormal eggs. The highest occurrence of cracks was in the RIR B line (2.2%). The BPR A line of hens had the highest concentration of shell-less eggs (1.7%), while the RIR A line, which also had the highest laying intensity (96.8%), had the highest frequency of double-yolk eggs (1.5%). A positive trend between the intensity and the occurrence of abnormal eggs was also confirmed. The BPR B (3.4%) and BPR C (3.0%) lines, which belonged to the lines with the lowest laying intensity, had the lowest percentage of abnormal eggs. For the BPR C line, cracks (1.2%), shell-less eggs (0.9%), and double-yolk eggs (0.9%) had the lowest occurrence rates. The correlation between laying intensity and double-yolk eggs reached 0.67, and a significant positive relationship was seen. On the other hand, no association was found between the laying intensity and the prevalence of cracked or shell-less eggs. There was also a strong correlation between abnormal eggs and double-yolk eggs (0.80) and between abnormal eggs and cracks (0.73). The correlation between the total occurrence of abnormal eggs and the intensity of laying reaches a mean value of 0.41. An increase in the intensity of laying from 80% to almost 100% leads to an increase in the occurrence of abnormal eggs from 2.6% to 6.3%.

Data about 4 474 high-yielding Estonian Holstein dairy cows from 14 herds was analysed for the impact of the first calving interval length (CI₁) on milk yield (MY) and lactation persistency. The results show that cows with CI₁ shorter than 12 months have on average 2 345 kg lower milk yield in the first 1 000 days of productive lifetime than those with CI₁ between 14 and 16 months. This is caused by lower MY in both the first and the second lactation as well as higher probability of being culled before reaching 1 000 days of productive life.

To satisfy increasing food and nutrient supply requirements for our growing future human population, farmers and staple food producers carry vital responsibilities. Especially farmers with ruminant livestock like dairy cows transform otherwise for human consumption unsuitable fibre into highly nutritious milk and meat. Nevertheless, dairy farmers are challenged increasingly by the consequences of global warming. Economic risks like feed supply and volatile commodity prices need to be balanced, also taking into account the increasing environmental awareness of end-customers. Focusing just on emissions, dairy production is contributing an essential part of the total carbon footprint emitted by the agricultural sector. Since rumen degradability of feed was identified by the Food and Agriculture Organization of the United Nations as one of the most influential parameters in reducing the carbon footprint of dairy farming, the desire to exploit leverage potential for efficiency increases can be considered exceptionally high. Although the positive effects of improved feed, in other words, neutral detergent fibre rumen degradability forpageContainerHideShow('srchdetcjs-202005-0001', false);