Archives Animal Breeding

Genetic diversity and population structure of indigenous guinea fowl ( in Benin using simple sequence repeat markers
Orounladji BM, Houndonougbo V, Adido MS, Soara AE, Hako Touko BA, Chrysostome CAAM and Tozo K
This study aimed to assess the genetic diversity and population structure of 12 guinea fowl phenotypes from three climatic zones (Guinean, Sudano-Guinean and Sudanian) of Benin. A total of 96 adult guinea fowl, aged at least 6 months, were selected for blood sampling. Fragment analysis was carried out using 17 polymorphic microsatellite markers. The informative marker combinations revealed a total of 83 alleles across all loci, with an average of 5 alleles per locus and a mean polymorphic information content (PIC) of 0.793. This study showed an observed heterozygosity of 0.492. The inbreeding coefficient values ranged from 0.086 in white phenotype to 0.226 in cinnamon, showing a deficit of heterozygotes, suggesting a moderate inbreeding level. A relatively low population differentiation was observed, with a mean fixation index (Fst) value of 0.033. The short genetic distances between phenotypes, unlike the strong genetic identities, revealed high genetic proximity between the 12 phenotypes of indigenous guinea fowl in Benin. These data indicate the existence of a single indigenous guinea fowl population with high intra-population genetic diversity with respect to climatic zones or phenotypes. This study will help in the selection of parental breeding stock for genetic improvement programs, as well as in the conservation for biodiversity maintenance and sustainable use of the indigenous guinea fowl in the study zones in Benin.
Genetic-parameter estimation of milk yield in White Maritza sheep breed using different test day models
Zhelyazkova P, Dimov D and Andonov S
The aims of this study were to estimate the genetic parameters of the test day milk yield (TDMY) of the White Maritza sheep breed population and to choose the most appropriate linear models for genetic-parameter estimation of test day milk yield. The White Maritza sheep breed is a multipurpose native sheep breed in Bulgaria. Test day milk yield data were collected from 1992 to 2015 (24 years). Milk yield recordings were made in 18 flocks according to the AC method (official milk recording by ICAR regulations). The database includes 8768 test day milk yield records belonging to 987 ewes. The pedigree file includes 1937 animals. Nine test day models (TDMs) were formulated and tested for the estimation of the genetic parameters of milk yield. The first three models were repeatability models (REP models), the second three were random regression models (RRMs), and the last three models were also random regression models with an added Ali and Schaeffer regression to describe the lactation curve using first-, second- and third-order polynomials. The average TDMY was 764.47 mL. There were no significant differences in the values of heritability () calculated by the three REP models: REP1 0.355  0.060, REP2 0.344  0.047 and REP3 0.347  0.060. The same applied to the repeatability coefficients, which, for the three REP models, were 0.384  0.065, 0.376  0.051 and 0.378  0.065, respectively. Based on REP model 1, three models with random regression RRM1, RRM2 and RRM3 were constructed, which is associated with the use of first-, second- and third-order polynomials (for the random effects of both the animal and the permanent environment). The trajectories of calculated by the three RRMs were not similar and demonstrated some differences, both at the beginning and in the middle of the milking period. The RRM with third-order polynomials demonstrated more genetic diversity until the 165th day of lactation, but Akaike information criterion (AIC), Bayesian information criterion (BIC) and log-likelihood (LogL) estimates were higher. The regression models with first- and second-degree polynomials were insufficient to reveal genetic diversity to a higher degree than REP model 1. The trend in the trajectories of calculated by the three random regression models with Ali and Schaeffer regression models (ASRMs) was similar to that of random regression models without the Ali and Schaeffer regression incorporated. Although the noted advantages of the random regression models revealed, to a greater extent, the genetic diversity of test day milk yield, AIC, BIC and LogL estimates indicated that repeatability models achieved a better balance between complexity and fitness and a smaller prediction error compared to random regression models.
Influence of horse demographics, country of training and race distance on the rating of Thoroughbreds
Sobotková E, Kopec T, Mikule V and Kuřitková D
The aim of the research was to assess how age, sex, sire, country of foaling, country of training and race distance influenced the international racing and performance of Thoroughbreds. The research was based on performance ratings of 6216 horses assigned by the International Federation of Racing Authorities between 2004 and 2022. The most common sex was stallion (58.54 %) and more than half of the population consisted of 3- and 4-year-old horses (54.68 %). The majority of the horses had the USA as their country of foaling (25.92 %) and also as their country of training (24.87 %). The sire with the largest number of offspring in the International Federation of Horseracing Authorities (IFHA) databases was Galileo (IRE) (193 horses). Four of the 10 most frequently represented sires belonged to the Sadler's Wells (USA) paternal line. The analysis of the statistics in the database as a whole established a significant () influence of all observed factors. Stallions achieved a significantly higher rating (117.85) compared to geldings (117.17) and mares (117.13). The horses originating in Ireland achieved a statistically higher rating (117.99) than horses from Argentina, Australia, Brazil, New Zealand, a group of other countries designated "Others" and South Africa. Statistically conclusive differences were found between horses trained in Ireland (118.80) and all other countries except Great Britain and France. Five of the 10 sires with the best offspring rating belong to the Mr. Prospector (USA) paternal line.
CircGUCY2C regulates cofilin 1 by sponging miR-425-3p to promote the proliferation of porcine skeletal muscle satellite cells
Qi K, Dou Y, Li C, Liu Y, Song C, Li X, Wang K, Qiao R, Li X, Yang F and Han X
Circular ribonucleic acids (or circRNAs) are an emerging class of endogenous noncoding RNAs that are involved in physiological and pathological processes. Increasing evidence suggests that circRNAs play an important regulatory role in skeletal muscle development and meat quality regulation. In this study, it was found that circGUCY2C exhibits a high expression level in the longissimus dorsi muscle. It shows resistance to RNase R and additionally promotes the mRNA expression of cyclin-dependent kinase 2 () and proliferating cell nuclear antigen (). Specifically, it was observed that the overexpression of circGUCY2C could promote the transition of porcine skeletal muscle satellite cells into the S and G2 phases of the cell cycle and that it regulates the proliferation of porcine skeletal muscle satellite cells. In contrast, miR-425-3p plays the opposite role and has an inhibitory effect on the proliferation of porcine skeletal muscle satellite cells. MiR-425-3p has been described as a target of circGUCY2C; consequently, the depletion of miR-425-3p promoted the proliferation of porcine skeletal muscle satellite cells. (cofilin 1) is a target of miR-425-3p, and circGUCY2C upregulated expression by inhibiting miR-425-3p. Collectively, our research outcomes demonstrate that circGUCY2C significantly influences the proliferation of porcine skeletal muscle satellite cells by selectively targeting the miR-425-3p- axis, and our work partially clarified the role of circGUCY2C in porcine skeletal muscle satellite cells. Thus, the study provides new insight into the function of circGUCY2C and adds to the knowledge of the post-transcriptional regulation of pork quality.
The effect of propolis addition to the laying-hen diet on performance, serum lipid profile and liver fat rate
Bölükbaşı ŞC, Ürüşan H and Apaydın Yıldırım B
The aim of this study was to evaluate the effect of propolis (P) on performance, egg quality parameters, serum lipid profile, some liver enzymes and liver fat ratio. One-hundred-and-twenty Lohmann (LSL) laying hens were divided into five groups, and each group consisted of six subgroups. The control group was fed basal diet. The other groups were fed high-energy (HE) diets to induce fatty liver syndrome, and 0, 100, 200 and 300 mg kg of propolis were supplemented with high-energy feeds. During the 8-week trial, feed and water were given ad libitum. It was determined that egg production and feed conversion ratio were decreased in the high-energy feed group without the addition of propolis. The highest egg production was found in HE  100 and HE  200 mg kg of P groups. It was found that liver fat ratios were higher in the group fed with HE  0 mg kg of P feed () than other groups. But the addition of P decreased the liver fat rate significantly. The highest very low density lipoprotein (VLDL), triglyceride (TG) and low-density lipoprotein (LDL) values were found for the HE  0 mg kg of P group. The addition of 200 mg kg of P to high-energy feed increased glutathione (GSH), superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) values. In conclusion, high-energy feed adversely affected egg production and liver fat ratio, but the addition of 100 or 200 mg kg of propolis improved egg production and decreased liver fat ratio.
The effect of two mineral-vitamin premixes on the blood biochemical parameters, milk yield and composition of Holstein-Friesian cows in Kazakhstan
Mussayeva GK, Shaykamal GI, Aitzhanova IN, Kazhiyakbarova A, Miciński J, Sobczak A, Meldebekova NA, Ilgekbayeva G and Rametov NM
The aim of this study was to determine the effect of two mineral-vitamin premixes on the health status (blood biochemical parameters), milk yield and composition of Holstein-Friesian (HF) cows in Kazakhstan. The study was performed on Holstein-Friesian cows kept on the Bek Plus dairy farm in the village of Korzhynkol, Fyodorovsky District, Kostanay Region. Forty primiparous cows, selected from the herd, were divided by the analogue method into two groups: a control group (C) and an experimental group (E) of 20 animals each. The diets fed to group E cows were supplemented with LI-R 18 PRO and PANTO Mineral R-77 Premium mineral-vitamin premixes. The premixes positively affected cow productivity and blood biochemical parameters, whose values were higher in group E than in group C. Higher levels of glucose, albumins and globulins exerted a beneficial influence on the health status of cows. No cases of lameness or metabolic diseases were recorded in group E. The yields of milk, protein and fat were higher in group E than in group C. Dietary supplementation with two premixes had no significant effect on the chemical composition of milk, including the values of the following parameters: somatic cell count (SCC), dry matter (DM), lactose (), casein (), acidity (), lactic acid (LA), density (, free fatty acids (FFAs), glucose () and urea ().
Inheritance of body size and ultrasound carcass traits in yearling Anatolian buffalo calves
Çinkaya S and Tekerli M
The body size and ultrasound carcass traits are related to the growth and muscling of animals. These characters promise future improvement through genetic selection in animal breeding. In breeding programs, knowing the (co)variance components serves to reveal the performance differences among animals and detection of suitable traits for selection. The research was carried out with 313 Anatolian buffalo calves born in 2019 at 36 farm operations. The least-square means for body weight (BW), wither height (WH), rump height (RH), body length (BL), chest width (CW), hip width (HW), chest circumference (CC), cannon-bone circumference (CBC), longissimus muscle area (LMA), longissimus muscle depth (LMD), and subcutaneous fat thickness (SFT) in yearling calves were 175.41  2.06 kg, 108.35  0.34, 111.85  0.37, 103.74  0.41, 33.93  0.23, 30.56   0.23, 135.18  0.60, 15.69  0.08 cm, 19.36  0.45 cm, 3.086  0.028, and 0.655  0.006 cm, respectively. The direct heritabilities for BW, WH, RH, BL, CW, HW, CC, CBC, LMA, LMD, and SFT were 0.334  0.032, 0.483  0.044, 0.473  0.043, 0.441  0.041, 0.364  0.034, 0.432  0.040, 0.435  0.040, 0.226  0.021, 0.0001  0.000, 0.300  0.026, and 0.539  0.046, respectively. The genetic and phenotypic correlations predicted in this study ranged from 0.02 to 0.90. All the genetic and phenotypic correlations among body size and ultrasound carcass traits were significant (), except for the genetic correlation between CW and HW. Some polymorphisms in , , , and genes were analyzed. Two single-nucleotide polymorphisms (SNPs) for and genes were found to be monomorphic in this buffalo population. Meanwhile, the effects of two SNPs in the and genes were not significant but showed some tendencies in the aspects of least-square means. The results of the study indicated that the Anatolian buffaloes have the potential to improve in growth and muscling characteristics.
Inbreeding in the Zwartbles breed population and its influence on meat production in the Czech Republic
Filipčík R, Falta D, Sokolová D, Hošek M, Pešan V and Kopec T
The aim of this study was to estimate the inbreeding coefficient in the Zwartbles sheep population in the Czech Republic, as well as to investigate the effect of inbreeding on meat yield indicators. The analysis used data on the entire population since 1997, with the original database containing 13 150 animals. In this population, the average inbreeding coefficient is 3.64 %. There is a significant increase in inbreeding - from zero values to more than 4 % between 1997 and 2021. The effect of inbreeding on the weight of the animals at 100 d of age, the weight at bonitation prior to breeding, the thickness of the (MLD), the thickness of the subcutaneous back fat, and the fleshiness of the animals were all evaluated. The value of the inbreeding coefficient had a statistically significant effect on weight at 100 d, MLD thickness, and back fat thickness. A negative relationship between inbreeding and all of these parameters was found when the inbreeding coefficient was increased by 1 %, resulting in a 60.2 g weight reduction at 100 d, 0.06 mm reduction in MLD thickness, and 0.013 mm reduction in back fat thickness.
Carcass composition and physicochemical and sensory attributes of breast and leg meat from native Mexican guajolote () as influenced by sex
Portillo-Salgado R, Herrera-Haro JG, Bautista-Ortega J, Ramírez-Bribiesca JE, Flota-Bañuelos C, Chay-Canul AJ and Cigarroa-Vázquez FA
The aim of the study was to compare carcass composition and physicochemical and sensory attributes of breast and leg meat from native Mexican guajolote () as influenced by sex. For this, slaughter weight and carcass characteristics of male () and female () guajolotes raised traditionally under extensive systems with similar housing and feeding conditions were recorded. Also, physical characteristics, proximate composition, the fatty acid profile, and sensory attributes were determined in breast and leg meat using standard procedures. The results showed that males had higher () slaughter weight, hot and cold carcass weights, and dressing percentage, as well as carcass part weights, while females had higher () abdominal fat weights than males. The lightness (), yellowness (), and drip loss values of breast meat, as well as redness () and water-holding capacity values of leg meat, were significantly () influenced by sex. Male breast meat had higher () moisture content, crude protein, erucic acid (C22:1n9),  MUFAs (total monounsaturated fatty acids),  UFAs (unsaturated fatty acids),  DFAs (desirable fatty acids),  UFA   SFA (total saturated fatty acid) ratio,  PUFA (total polyunsaturated fatty acid)   SFA ratio, and chewiness scores than females. Likewise, leg meat from males showed higher () ash content, myristic acid (C14:0), palmitic acid (C16:0), stearic acid (C18:0), oleic acid (C18:1n9c), palmitoleic acid (C16:1n7),  SFAs,  OFAs (odd fatty acids), thrombogenic index, and atherogenic index, whereas females had high fat content. In conclusion, it would be suggested that, from a nutritional point of view, the meat from male guajolotes was preferable to the meat from females.
Genome-wide single nucleotide polymorphism (SNP) data reveal potential candidate genes for litter traits in a Yorkshire pig population
Zhang Y, Lai J, Wang X, Li M, Zhang Y, Ji C, Chen Q and Lu S
The litter trait is one of the most important economic traits, and increasing litter size is of great economic value in the pig industry. However, the molecular mechanisms underlying pig litter traits remain elusive. To identify molecular markers and candidate genes for pig litter traits, a genome-wide association study (GWAS) and selection signature analysis were conducted in a Yorkshire pig population. A total of 518 producing sows were genotyped with Illumina Porcine SNP 50 BeadChip, and 1969 farrowing records for the total number born (TNB), the number born alive (NBA), piglets born dead (PBD), and litter weight born alive (LWB) were collected. Then, a GWAS was performed for the four litter traits using a repeatability model. Based on the estimated breeding values (EBVs) of TNB, 15 high- and 15 low-prolificacy individuals were selected from the 518 sows to implement selection signature analysis. Subsequently, the selection signatures affecting the litter traits of sows were detected by using two methods including the fixation index (FST) and . Combining the results of the GWAS and selection signature analysis, 20 promising candidate genes (, , , , , , , , , , , , , , , , , , , and ) were identified. These findings provide novel insights into the genetic basis of pig litter traits and will be helpful for improving the reproductive performances of sows in pig breeding.
Detection of genetic variations in the and genes in Kazakh meat-wool sheep
Amandykova M, Orazymbetova Z, Kapassuly T, Kozhakhmet A, Khamzina S, Iskakov K and Dossybayev K
Kazakh meat-wool sheep are of great interest because of the intrabreed multifetal type's high productivity of 140 %-160 %. Genes encoding growth differentiation factor-9 () and bone morphogenetic protein 15 () are promising candidates for studying sheep productivity, as they affect fertility in mammals, including sheep. Thus, the purpose of this study was to assess the fertility of the Kazakh meat-wool sheep breed based on and candidate genes of fecundity for the selection of animals with valuable genotypes. We selected 300 heads of the Kazakh meat-wool sheep breed from two populations for PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism) analysis, 15 of which were subsequently used for sequencing of exon regions of the and genes. The sheep populations were tested for G1 and G8 mutations of the gene and B2 and B4 mutations of the gene. The PCR-RFLP analysis revealed that 59 (19.7 %) of the 300 Kazakh meat-wool breed sheep were heterozygous carriers of the G1 mutation (genotype AG) of the gene, and sequencing analysis supported these results. The comparative phylogenetic analysis showed a clear separation of Kazakh meat-wool sheep wild types and carriers of the G1 mutation. This mutation was reported to have a relationship with the animals' litter size in other sheep breeds. For this reason, similar relationships should be investigated in Kazakh meat-wool sheep. However, G8, B2, and B4 mutations were not detected among the studied animal populations, showing that these mutations are not characteristic of the Kazakh meat-wool sheep breed.
Polymorphism and expression of in relation to reproductive performance in Jining Grey goats
Wang W, Wang Y, Liu Y, Cao G, Di R, Wang J and Chu M
Understanding the molecular mechanism of mammalian reproduction (puberty and prolificacy) will play a part in improving animal reproductive performance. (glutamate dehydrogenase 1) is important for mammalian reproduction, as shown in previous studies; however, its roles in puberty and prolificacy have rarely been reported. In this study, we designed seven pairs of primers (P1 to P7) for cloning and sequencing genomic DNA of Jining Grey goats and Liaoning Cashmere goats. Primer 8 (P8) was designed to detect single nucleotide polymorphism (SNP) of the in both sexually precocious and high-fecundity breeds (Jining Grey, Nanjiang Brown and Matou goats) and sexually late-maturing and low-fecundity breeds (Liaoning Cashmere, Inner Mongolia Cashmere and Taihang goats) by PCR-RFLP (restriction fragment length polymorphism). The real-time quantitative polymerase chain reaction (RT-qPCR) technique was used to detect the expression of in a variety of tissues. The results showed that the A197C mutation was only found in the amplification product of P6. For this SNP locus, only two genotypes (AA and AC) were detected in Nanjiang Brown goats, while three genotypes (AA, AC and CC) were detected in the other five breeds. In Jining Grey goats, the frequency of genotypes AA, AC and CC was 0.69, 0.26 and 0.05, respectively. In Jining Grey goats, AA genotype had 0.54 () and 0.3 () more kids than the CC and AC genotype, respectively, and no significant difference () was found in kidding number between the AC and CC genotype. was expressed in five tissues of different developmental stages. The expression level of in the hypothalamus was higher than that in the other four tissues except during puberty of Liaoning Cashmere goats. In puberty in goats, expression was significantly higher in ovaries than that in the juvenile period (). RT-qPCR results showed that the expression of in ovaries may relate to the puberty of goats. The present study preliminarily indicated that there might be an association between the 197 locus of and sexual precocity in goats, and allele A of was a potential DNA marker for improving kidding number in Jining Grey goats.
The effect of nanosilver-based preparation on microbiological quality of poultry litter
Czyż K, Dobrzański Z, Kowalska-Góralska M, Senze M and Wyrostek A
The study aimed to examine an effect of the preparation based on nanosilver suspension on mineral carrier on poultry litter microbiological profile. The study was conducted on Ross 308 broiler chickens. Three groups were formed, 84 birds in each. Preparation used in the study was composed of aqueous nanosilver suspension sprayed on mineral sorbent. Birds were maintained on straw-sawdust litter; the groups were differentiated due to preparation application (C - control without preparation, I - preparation applied once at the beginning, II - preparation added each week). Pooled litter samples were collected from the top layer of the litter (six samplings) in order to determine mesophilic bacteria count. Additionally, on the last day of the experiment litter samples were collected from three points (by drinker, feeder, pen corner) to analyze the total number of microorganisms, spp., , , and molds. In the case of mesophilic bacteria count, the highest decrease was noted for group II. Total number of microorganisms determined in various points of the pen did not give clear relationship; in some cases even an increase was found. spp. decreased as a result of preparation addition; the highest decrease was noted for samples collected by feeders. The results for are not unequivocal. However, a decrease was found in the case of drinkers and feeders compared to control, especially in group II. An addition of preparation caused a decrease in , especially for samples collected by feeders in group II. Similar tendency was found for molds. The study demonstrated that the preparation exhibits bactericidal properties. However, its effect varies depending on microorganism kind and sample collection point.
Trace mineral concentrations and accretion rates in the empty body and body tissues of growing Fleckvieh (German Simmental) bulls
Honig AC, Inhuber V, Spiekers H, Windisch W, Götz KU, Strauß G and Ettle T
This research project aimed to generate basic data for specifying the trace mineral requirements of Fleckvieh (German Simmental) bulls. Hence, the concentrations of the trace minerals iron (Fe), zinc (Zn), copper (Cu), and manganese (Mn) in the empty-body and body tissue fractions of growing Fleckvieh bulls slaughtered at 120-780 kg live weight were determined. Results were used to calculate trace mineral accretion rates. Fe and Zn represented the largest shares in the animals' bodies. The Zn accretion increased, while Mn accretion steadily declined during cattle growth. Fe accretion attained a maximum at 400 kg live weight. Cu accretion declined until 600 kg live weight and then increased slightly afterwards. The provided data may be used to adjust the recommendations with respect to the trace mineral requirements of growing Fleckvieh bulls.
Determination of the effect of pre-mating weight and placental characteristics on birth weight in Karayaka sheep
Urun S and Şirin E
The aim of this study was to determine the effect of the pre-mating weight and placental characteristics on birth weight. Data were collected from 62 Karayaka ewes and 70 Karayaka lambs. The placental characteristics considered were placental weight, placental area and the number of cotyledons. The Pearson correlation coefficient was used for statistical comparison and the determination of relationships between variables. In addition, correlation coefficients between live weights and placental characteristics were determined. The average birth weight (BW), pre-mating weight (PMW), placental weight (PW), placental area (PA) and cotyledon number (CN) values were 4.37  0.70 kg, 50.22  5.63 kg, 362.51  118.42 g, 994.18  312.76 cm and 56.93  8.06, respectively. BW had positive correlations with PMW (0.147), birth type (BT) (0.643), PW (0.604), PA (0.323) and CN (0.161) (  0.05). BW had negative correlations with maternal age (MA) () (  0.05). PMW had positive correlations with maternal age (MA) (0.237) (  0.05). PMW had negative correlations with S (sex) (), PW (), PA () and CN () (  0.05).
Novel MHC gene polymorphism and its association with IgY concentration and Newcastle disease antibody titer in IPB-D2 chickens
Lestari D, Murtini S, Ulupi N, Gunawan A and Sumantri C
This study aimed to identify the polymorphism of the B Locus Beta 2 () gene and its association with immunoglobulin Y (IgY) concentration and Newcastle disease (ND) antibody titer; we analyzed gene expression in different categories of ND antibody titers in IPB-D2 chickens. The total sample used was 100 IPB-D2 chickens. Blood samples were collected at 21 weeks old for an ELISA (enzyme-linked immunoassay) test, an HI (hemagglutination inhibition) test, and genotyping. The method for polymorphism was Sanger sequencing. Analysis of gene expression was performed using the cecal tonsil tissue of IPB-D2 chickens. Polymorphism data were analyzed using SNPstats and DNAsp (DNA Sequence Polymorphism) software. The association of the single-nucleotide polymorphisms (SNPs) with IgY concentration and ND antibody titer was analyzed using SAS software (version 9.2). The genotype mean values were compared by means of a T test. The relative mRNA expression analysis was performed using a quantitative real-time polymerase chain reaction (qRT-PCR). The results showed that 13 SNPs were found in exon 2 and exon 3 in the gene. As many as 4 out of the 13 SNPs were associated with IgY concentration. As many as 9 out the 13 SNPs may have changed amino acids. The Ct value showed that the expression of the gene in IPB-D2 chickens with high ND antibody titers is higher than IPB-D2 chickens with low ND antibody titers. In conclusion, the AA genotype of g.458 T  A was associated with high IgY concentrations, and the gene presented with a high expression in IPB-D2 chickens with high ND antibody titers.
Intermittent light program impacts on reproductive performance, health and welfare of breeding hens
Farghly MFA, Alhotan RA, Mahrose KM, Attia YA, Abdelfattah M, Abougabal M, Taboosha M, Ghonime M, Shaaban M, Losacco C and Tufarelli V
The lighting regime significantly impacts poultry production, reproductive performance, health and welfare. This study aimed to test the effect of the intermittent light (IL) regime on reproductive organs and hormones, semen quality, and behavioral performance. Thus, 270 Rhode Island Red hens aged 20 weeks were distributed among three groups of six replicates and 15 birds each, housed in floor pens. The first group was used as a control (C) and was exposed to constant light for 16 h d, while birds in other groups were exposed to IL for 20 min h (T20) and 40 min h (T40) during the 16 h light period. The outcomes were that follicle number was higher for T20 compared to T40 but not the controls, while T40 is different from T20 but not the controls. The same is true for testosterone. The sperm concentration is lower for T40 compared to the controls, with no difference between T20 and the controls. Body temperature was not different among groups. Conversely, differences were not noticed for leg alterations; plumage conditions; and relative ovary, oviduct, and/or testes weight and hatchability. Thus, the IL T20 program should be further investigated as a lighting regimen for managing Rhode Island Red laying hens for stimulating follicle number and testosterone without negatively impacting the physiological response and health traits. From a practical point of view, the IL schedule of 20 min h during 20-36 weeks of age can be economically viable due to saving 66 % of the light cost.
Characteristics of meat production traits in the Hungarian Simmental herd selected for the simultaneous improvement of milk and meat production
Polgár JP, Szabó F, Kovács Á, Kovács-Mesterházy Z and Bene S
Phenotypic and genetic trends, population genetic parameters, and the heritability and breeding values of the fattening and slaughter traits - namely muscularity score (MUS), final fattening weight (FFW), weight gain per day of life (WGD), slaughter weight (SLW), carcass weight (CAR), dressing percentage (DRP), bone-meat production per day of life (BMP), SEUROP conformation and fat coverage score (EUR, FAT), and meat percentage (MEP) - of 1162 Hungarian Simmental bulls were evaluated with the progeny test database of the Association of Hungarian Simmental Breeders. Trends were calculated by weighted linear regression analysis, while the population genetic parameters and breeding values used the BLUP (best linear unbiased prediction) animal model and general linear model (GLM). According to the results, the lowest heritability value () was found in FAT. In the case of MUS, EUR and MEP, the values were moderate (, 0.26 and 0.32), and in the case of the other traits, high heritability values (  0.42-0.52) were estimated. The phenotypic trends of the fattening and slaughter traits of bull progeny born between 2001 and 2019 showed a stagnant direction. Between the sires, the differences in the breeding values for some traits (WDG, CAR and BMP) were large, and with other traits (DRP, EUR and FAT), small differences were found. According to the data of the genetic-trend calculation, the steepness values of the evaluated traits were positive, and the genetic trends showed a slightly improving direction in the estimated period.
Milk-y Way: the impact of single-nucleotide polymorphisms on milk production traits in Kilis dairy goats
Gündüz Z and Biçer O
This study aimed to investigate the impact of single-nucleotide polymorphisms (SNPs) on milk production traits in Kilis dairy goats by analyzing the genotypes of , , , , and genes and their association with lactation milk yield (LMY), lactation length (LL) and average daily milk yield (ADMY). Blood samples were collected from 227 goats, and genotyping was performed using polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP). The results revealed that the frequencies of the genotypes varied among the genes. The polymorphisms were found to be significantly linked with milk production traits. These findings suggest that SNPs of , and are significantly associated with LMY and that the genotype, genotype and genotype are associated with higher LMY and ADMY. Additionally, the genotype was found to have a longer LL. However, no significant association was found between the and genotypes and LMY, LL and ADMY. Overall, this study provides valuable insights into the genetic factors influencing milk production traits in Kilis dairy goats, which can be utilized for the selection of high-yielding animals in breeding programs.
The trend of breeding value research in animal science: bibliometric analysis
Yardibi F, Chen C, Fırat MZ, Karacaören B and Süzen E
This study aims to identify trends and hot topics in breeding value to support researchers in finding new directions for future research in that area. The data of this study consist of 7072 academic studies on breeding value in the Web of Science database. Network visualizations and in-depth bibliometric analysis were performed on cited references, authors, countries, institutions, journals, and keywords through CiteSpace. VanRaden (2008) is the most cited work and has an essential place in the field. The most prolific writer is Ignacy Misztal. While the most productive country in breeding value studies is the United States, the People's Republic of China is an influential country that has experienced a strong citation burst in the last 3 years. The National Institute for Agricultural Research and Wageningen University are important institutions that play a critical role in connecting other institutions. Also, these two institutions have the highest centrality values. "Genomic prediction" is the outstanding sub-study field in the active clusters appearing in the analysis results. We have summarized the literature on breeding value, including publication information, country, institution, author, and journal. We can say that hot topics today are "genome-wide association", "feed efficiency", and "genomic prediction". While the studies conducted in the past years have focused on economic value and accuracy, the studies conducted in recent years have started to be studies that consider technological developments and changing world conditions such as global warming and carbon emission.
Growth performance, blood lipids, and fat digestibility of broilers fed diets supplemented with bile acid and xylanase
Alzawqari MH, Shukry Atta M, Metwally A, Selim S, Wadaan MAM, Kim IH, Cho S, Eltahan HM, Alagawany M, Alhotan RA, Al Sulaiman AR, Hussein EO and Saleh AA
This study aimed to show the effect of bile acid (BA) and xylanase (Xyl) supplementation on the growth, fat digestibility, serum lipid metabolites, and ileal digesta viscosity of broilers. A total of 720 1 d old male broilers were allocated to one of nine treatments with four replicates in each under a factorial design arrangement of three levels of BA (0 %, 0.25 %, and 0.50 %) and three levels of Xyl (0 %, 0.05 %, and 0.10 %) supplementation. The duration of the experiment was 35 d (7-42 d). Growth performance, blood lipids, fat digestibility, and ileal digesta viscosity were determined. The experimental treatments did not affect feed intake (FI) and weight gain (WG). Supplementation of BA or Xyl did not significantly ameliorate the feed conversion rate (FCR) (). The addition of BA linearly increased fat digestibility. At 7-21 d of age, the addition of BA or Xyl had a significant () increase in serum cholesterol (Chol) but no significant difference for other serum lipid parameters in broiler chickens fed with Xyl in the starter and grower periods. However, the supplementation of 0.5 % BA at 7-21 d of age significantly increased the Chol and low-density-lipoprotein (LDL) levels. The results of this trial revealed that the supplementation of xylanases had a great effect on the degradation of arabinoxylan from wheat, which led to a relatively greater reduction in ileal digesta viscosity; it was also found that supplementation of BA significantly increased the concentration of serum lipid metabolites, whereas BA and Xyl supplementation linearly increased the fat digestibility of the birds fed wheat and tallow diets.