Identifying the Potential Apoptotic Metabolites in Postmortem Beef Muscle by Targeted Metabolomics.

Apoptotic cells may release specific metabolites to act as messengers during the apoptotic process. This study represents the first attempt to identify potential apoptotic metabolites in postmortem muscle. Ninety potential apoptotic metabolites in beef were selected and analyzed through targeted metabolomics, with 84 of them exhibiting significant differences over the postmortem time. Following the addition of the mitochondria-targeted antiapoptotic agent mitoquinone to postmortem muscle, metabolomic analysis revealed that 73 apoptotic metabolites still underwent significant changes, even against the backdrop of altered apoptosis. Of these 73 apoptotic metabolites, 54 exhibited similar trends at various treatment times with adding mitoquinone, including lipids (6), amino acids (27), nucleosides (11), and carbohydrate and energy metabolism (10). Mitoquinone significantly reduced the levels of most apoptotic metabolites, and inhibition of apoptosis resulted in a significant decrease in the levels of numerous apoptotic metabolites. Consequently, these apoptotic metabolites are considered complementary to apoptosis in postmortem muscle, with their increased levels potentially promoting apoptosis. Noteworthy apoptotic metabolites, such as glycerol 3-phosphate, serine, AMP, ATP, GMP, and creatine, were identified as active signaling molecules that attract and recruit phagocytes during apoptosis, assisting in recognizing apoptotic cells by phagocytes. This study provides, for the first time, insights into potential apoptotic metabolites in postmortem muscle, contributing to a better understanding of meat biochemistry.

LncRNA BlncAD1 Modulates Bovine Adipogenesis by Binding to MYH10, PI3K/Akt Signaling Pathway, and miR-27a-5p/CDK6 Axis.

Research on adipogenesis will help to improve the meat quality of livestock. Long noncoding RNAs (lncRNAs) are involved in mammalian adipogenesis as epigenetic modulators. In this study, we analyzed lncRNA expression during bovine adipogenesis and detected 195 differentially expressed lncRNAs, including lncRNA BlncAD1, which was significantly upregulated in mature bovine adipocytes. Gain- and loss-of-function experiments confirmed that BlncAD1 promoted the proliferation, apoptosis, and differentiation of bovine preadipocytes. RNA pull-down revealed that the nonmuscle myosin 10 (MYH10) is a potential binding protein of BlncAD1. Then, we elucidated that loss of BlncAD1 caused increased ubiquitination of MYH10, which confirmed that BlncAD1 regulates adipogenesis by enhancing the stability of the MYH10 protein. Western blotting was used to demonstrate that BlncAD1 activated the PI3K/Akt signaling pathway. Bioinformatic analysis and dual-luciferase reporter assays indicated that BlncAD1 competitively absorbed miR-27a-5p. The overexpression and interference of miR-27a-5p in bovine preadipocytes displayed that miR-27a-5p inhibited proliferation, apoptosis, and differentiation. Further results suggested that miR-27a-5p targeted the CDK6 gene and that BlncAD1 controlled the proliferation of bovine preadipocytes by modulating the miR-27a-5p/CDK6 axis. This study revealed the complex mechanisms of BlncAD1 underlying bovine adipogenesis for the first time, which would provide useful information for genetics and breeding improvement of Chinese beef cattle.

Influences of oxidative stress and energy balance on pregnancy rates after the transfer of embryos to repeat-breeder Japanese Black cattle.

The purpose of this study is to reassess our previously reported findings on the diminished pregnancy rate of embryo transfer (ET) in summer for repeat-breeder (RB) cows compared with other seasons, with a focus on oxidative stress and energy balance. The study involved Japanese Black cattle, including 224 heifers (aged <3 years) and 278 (aged <9 years) cows with one or more deliveries, defined as RB animals. Evaluation of the effects of season on pregnancy rates revealed significantly lower rates in RB cows during summer compared with spring and autumn. Moreover, serum malondialdehyde (MDA) concentration in RB cows during summer was significantly higher than in winter, with no difference in RB heifers. Seasonal effects on serum nonesterified fatty acid (NEFA) concentration in both RB heifers and RB cows showed no significant differences. However, median MDA and NEFA concentrations in RB cows were significantly elevated compared with RB heifers, suggesting that factors contributing to low fertility should consider parity. Furthermore, our study indicated that RB cows were under oxidative stress, as demonstrated by significantly elevated MDA concentrations compared with normally reproducing cows in summer. Further investigation is necessary to gain a better understanding of these observations in the future.

Gene expression of free fatty acids-sensing G protein-coupled receptors in beef cattle.

Many physiological functions are regulated by free fatty acids (FFA). Recently, the discovery of FFA-specific G protein-coupled receptors (FFARs) has added to the complexity of their actions at the cellular level. The study of FFAR in cattle is still in its earliest stages focusing mainly on dairy cows. In this study, we set out to map the expression of genes encoding FFARs in 6 tissues of beef cattle. We also investigated the potential effect of dietary forage nature on FFAR gene expression. To this end, 16 purebred Charolais bulls were fed a grass silage ration or a maize silage ration (n = 8/group) with a forage/concentrate ratio close to 60:40 for 196 d. The animals were then slaughtered at 485 ±â€…42 d and liver, spleen, ileum, rectum, perirenal adipose tissue (PRAT), and Longissimus Thoracis muscle were collected. FFAR gene expression was determined by real-time quantitative PCR. Our results showed that of the five FFARs investigated, FFAR1, FFAR2, FFAR3, and GPR84 are expressed (Ct < 30) in all six tissues, whereas FFAR4 was only expressed (Ct < 30) in PRAT, ileum, and rectum. In addition, our results showed that the nature of the forage, i.e., grass silage or maize silage, had no effect on the relative abundance of FFAR in any of the tissues studied (P value > 0.05). Taken together, these results open new perspectives for studying the physiological role of these receptors in beef cattle, particularly in nutrient partitioning during growth.

Free fatty acids (FFA) are key modulators of bovine physiology. Recently, it has been discovered that some G protein-coupled receptors, termed free fatty acid receptors (FFARs), may help mediate the action of FFA at the cellular level. In humans and rodents, a growing body of evidence has shown that i) FFARs are expressed in a wide range of tissues and ii) FFARs are involved in the regulation of major FFA-dependent physiological processes (inflammation, feed intake, insulin release, etc.). In cattle, information on FFAR expression and function in tissues are scarce and mainly concern dairy cows. In this study, we showed that FFARs are expressed in 6 different tissues of beef cattle: adipose tissue, muscle tissue, ileum, rectum, liver, and spleen. We also showed that the nature of forage fed to the animals (i.e., grass silage vs. maize silage) has no effect on FFARs gene expression.

Investigating the Role of KLF6 in the Growth of Bovine Preadipocytes: Using Transcriptomic Analyses to Understand Beef Quality.

Intramuscular fat is a crucial determinant of carcass quality traits like tenderness and taste, which in turn is influenced by the proliferation of intramuscular preadipocytes. This study aimed to investigate the Krüppel-like factor 6 (KLF6)-mediated proliferation of bovine preadipocytes and identify underlying molecular mechanisms. Down-regulation of KLF6 by siKLF6 resulted in a significant (p < 0.01) suppression of cell cycle-related genes including CDK1, MCM6, ZNF4, PCNA, CDK2, CCNB1, and CDK6. Conversely, the expression level of p27 was significantly (p < 0.01) increased. Moreover, EdU (5-ethynyl-20-deoxyuridine) staining revealed a significant decrease in EdU-labeled cells due to KLF6 down-regulation. Collectively, these findings indicate that KLF6 down-regulation inhibits adipocyte proliferation. Furthermore, RNA sequencing of preadipocytes transfected with siKLF6 and NC, followed by differential gene expression analysis, identified 100 up-regulated and 70 down-regulated genes. Additionally, the differentially expressed genes also significantly influenced various Gene Ontology (GO) terms related to cell cycle, nuclear chromosomes, and catalytic activity on DNA. Furthermore, the top 20 pathways enriched in these DEGs included cell cycle, DNA replication, cellular senescence, and homologous recombination. These GO terms and KEGG pathways play key roles in bovine preadipocyte proliferation. In conclusion, the results of this study suggest that KLF6 positively regulates the proliferation of bovine preadipocytes.

Intake, digestibility, energy and nitrogen utilisation, and enteric methane emission in Holstein and Girolando-F1 cows during the transition period.

This study aimed to evaluate intake, energy and nitrogen balance as well as methane emission in Holstein and ½ Holstein ½ Gyr (Girolando-F1) cows during the transition period. Twenty-four cows (12 Holstein and 12 Girolando-F1) were used to evaluate feed intake, apparent digestibility, heat production and methane emission, carried out in two periods: from 28 to 19 days pre-calving and from 15 to 23 days post-calving. A completely randomised design was used and data were analysed by ANOVA within periods (pre- and post-calving) considering the main effect of genetic groups. Girolando-F1cows presented greater body condition score (BCS) compared with Holstein. During pre-calving, there were no differences between genetic groups, except for highest heat production per kilogram of metabolic body weight for Holstein cows. After calving, Holstein cows had greater intake of DM, nitrogen, NDF per kg of BW and produced more heat per kg of metabolic body weight. Holstein cows yielded more milk and fat-corrected milk (FCM4%) compared with Girolando-F1 cows. Holstein cows presented higher methane emission per unit of BW and of metabolic weight. Emissions of enteric methane per kilogram of milk and per kilogram of FCM4% tended to be lower for Holstein compared with Girolando-F1 cows. Nitrogen and energy retention were similar for both Holstein and Girolando-F1 at pre- and post-calving. Despite differences in BCS, DMI, and milk yield, Girolando-F1 and Holstein cows present overall similar energy efficiency, albeit Holstein cows tended to present less methane emission per kg of eligible product (milk).

FSH Regulates YAP-TEAD Transcriptional Activity in Bovine Granulosa Cells to Allow the Future Dominant Follicle to Exert Its Augmented Estrogenic Capacity.

The molecular mechanisms that drive the granulosa cells' (GC) differentiation into a more estrogenic phenotype during follicular divergence and establishment of follicle dominance have not been completely elucidated. The main Hippo signaling effector, YAP, has, however, emerged as a potential key player to explain such complex processes. Studies using rat and bovine GC demonstrate that, in conditions where the expression of the classic YAP-TEAD target gene tissue growth factor (CTGF) is augmented, CYP19A1 expression and activity and, consequently, estradiol (E2) secretion are reduced. These findings led us to hypothesize that, during ovarian follicular divergence in cattle, FSH downregulates YAP-TEAD-dependent transcriptional activity in GC to allow the future dominant follicle to exert its augmented estrogenic capacity. To address this, we performed a series of experiments employing distinct bovine models. Our in vitro and ex vivo experiments indicated that indeed FSH downregulates, in a concentration-dependent manner, mRNA levels not only for CTGF but also for the other classic YAP-TEAD transcriptional target genes ANKRD1 and CYR61 by a mechanism that involves increased YAP phosphorylation. To better elucidate the functional importance of such FSH-induced YAP activity regulation, we then cultured GC in the presence of verteporfin (VP) or peptide 17 (P17), two pharmacological inhibitors known to interfere with YAP binding to TEADs. The results showed that both VP and P17 increased CYP19A1 basal mRNA levels in a concentration-dependent manner. Most interestingly, by using GC samples obtained in vivo from dominant vs. subordinate follicles, we found that mRNA levels for CTGF, CYR61, and ANKRD1 are higher in subordinate follicles following the follicular divergence. Taken together, our novel results demonstrate that YAP transcriptional activity is regulated in bovine granulosa cells to allow the increased estrogenic capacity of the selected dominant follicle.

Molecular characterization of TRIB1 gene and its role in regulation of steroidogenesis in bos grunniens granulosa cells.

To explore the expression pattern of the TRIB1 gene in yak follicles and its effect on the steroidogenesis of granulosa cells (GCs). Here, 4-5 years old female yaks were treated as the subjects. Immunohistochemically assay found that TRIB1 protein was expressed in different developmental follicles. Among different cell types of follicles, including cumulus cells (CCs), granulosa cells (GCs) and theca cells (TCs), the TRIB1 protein was most abundant in GCs (P < 0.0001). In addition, we cloned the coding sequence (CDS) of the yak TRIB1 gene, which is 1119 bp, encoding 372 amino acids (AA). The amino acid sequence homology of TRIB1 is >80% to those of other species, except for zebrafish. To further explore the function of TRIB1 in steroidogenesis, the pcDNA3.1(+)-TRIB1 eukaryotic expression vector was constructed and then transfected into GCs. The data showed that overexpression of TRIB1 significantly reduced the progesterone (P4) secretion of granulosa cells measured by ELISA assay (P < 0.05), but not Estradiol (E2) secretion. Consistently, TRIB1 gain-of-function downregulated the mRNA levels of steroidogenesis related genes steroidogenic acute regulatory protein (StAR), cytochrome P450 family 11 subfamily A member 1 (CYP11A1) and 3ß-hydroxysteroid dehydrogenase (3ß-HSD) (P < 0.01), while cytochrome P450 family 17 subfamily A member 1 (CYP17A1) and cytochrome P450 family 19 subfamily A member 1 (CYP19A1) had no significant difference (P > 0.05). Interestingly, mito-tracker staining showed that mitochondrial number significantly decreased in TRIB1 overexpressed GCs (P < 0.01). Further, overexpression of TRIB1 inhibited mRNA levels of mitochondrial biogenesis related genes, including Mitochondrial transcription factor (TFAM) and Peroxisome proliferator-activated receptor alpha co-activator (PPARGC1A) (P < 0.05). Conclusively, this work indicates that TRIB1 inhibited progesterone synthesis of GCs might be involved in the reduction of the mitochondria number.

In-line near-infrared analysis of milk coupled with machine learning methods for the daily prediction of blood metabolic profile in dairy cattle.

Precision livestock farming technologies are used to monitor animal health and welfare parameters continuously and in real time in order to optimize nutrition and productivity and to detect health issues at an early stage. The possibility of predicting blood metabolites from milk samples obtained during routine milking by means of infrared spectroscopy has become increasingly attractive. We developed, for the first time, prediction equations for a set of blood metabolites using diverse machine learning methods and milk near-infrared spectra collected by the AfiLab instrument. Our dataset was obtained from 385 Holstein Friesian dairy cows. Stacking ensemble and multi-layer feedforward artificial neural network outperformed the other machine learning methods tested, with a reduction in the root mean square error of between 3 and 6% in most blood parameters. We obtained moderate correlations (r) between the observed and predicted phenotypes for γ-glutamyl transferase (r = 0.58), alkaline phosphatase (0.54), haptoglobin (0.66), globulins (0.61), total reactive oxygen metabolites (0.60) and thiol groups (0.57). The AfiLab instrument has strong potential but may not yet be ready to predict the metabolic stress of dairy cows in practice. Further research is needed to find out methods that allow an improvement in accuracy of prediction equations.

Blood and adipose tissue steroid metabolomics and mRNA expression of steroidogenic enzymes in periparturient dairy cows differing in body condition.

In high-yielding dairy cows, the rapidly increasing milk production after parturition can result in a negative nutrient balance, since feed intake is insufficient to cover the needs for lactation. Mobilizing body reserves, mainly adipose tissue (AT), might affect steroid metabolism. We hypothesized, that cows differing in the extent of periparturient lipomobilization, will have divergent steroid profiles measured in serum and subcutaneous (sc)AT by a targeted metabolomics approach and steroidogenic enzyme profiles in scAT and liver. Fifteen weeks antepartum, 38 multiparous Holstein cows were allocated to a high (HBCS) or normal body condition (NBCS) group fed differently until week 7 antepartum to either increase (HBCS BCS: 3.8 ± 0.1 and BFT: 2.0 ± 0.1 cm; mean ± SEM) or maintain BCS (NBCS BCS: 3.0 ± 0.1 and BFT: 0.9 ± 0.1 cm). Blood samples, liver, and scAT biopsies were collected at week -7, 1, 3, and 12 relative to parturition. Greater serum concentrations of progesterone, androsterone, and aldosterone in HBCS compared to NBCS cows after parturition, might be attributed to the increased mobilization of AT. Greater glucocorticoid concentrations in scAT after parturition in NBCS cows might either influence local lipogenesis by differentiation of preadipocytes into mature adipocytes and/or inflammatory response.

The metabolomics profile of growth rate in grazing beef cattle.

This study aimed to determine the relationship between the metabolome and changes in growth rate (i.e., liveweight change, LWC) and molasses-lick block supplement intake (MLB) of grazing cattle. Weaner beef cattle were fed for 220 days with a sequence of feed types and blood samples, growth rate, and supplement intake were taken on five points in time. The relative abundance (RA) of plasma metabolites were determined using proton nuclear magnetic resonance (NMR). Sixty-four per cent of the metabolites identified were associated with LWC but only 26% with MLB intake (P < 0.05). Periods with faster growth rate showed high availability of amino acids (i.e., valine, leucine, isoleucine, phenylalanine and tyrosine), acetate, and 3-hydroxybutyrate. Periods with lower growth rate were associated with high RA of lipids, choline and acetate. The metabolic profile of individual animals during a period of compensatory growth (after periods of poor performance) showed that high-performing animals were characterised by lower RA of amino acids (i.e., valine, leucine, isoleucine, methylhistidine), creatinine, creatine, pyruvate, 3-hydroxybutyrate, and acetyl groups. It is speculated that high-performing animals have faster uptake of these metabolites from the bloodstream. Cattle growth rate over time was associated with their metabolome which could be used to ensure that the availability of certain metabolites promoting growth is tailored in feed supplements to improve production.

Effect of Diet Supplementation with the Mycotoxin Binder Montmorillonite on the Bioavailability of Vitamins in Dairy Cows.

The objective of this study was to determine the effect of the mycotoxin binder montmorillonite (MMT) supplemented in the diet of dairy cows on the bioavailability of vitamins A, D, E, B1 and B6. Six multiparous Holstein-Friesian cows were used in a crossover design with two periods. Treatments were a control diet with or without MMT. Vitamins were infused individually into the abomasum through the ruminal cannula. Blood samples were collected from the jugular vein at 0, 1, 2, 3, 4, 6, 9, 12, 24 and 48 h after the administration of each vitamin. Results showed that vitamin A reached maximal concentration (Tmax) at 5.3 h after dosing, the maximal concentration (Cmax) was 1.2 times higher than the basal concentration (Cbasal), and the area under the curve (AUC) was 739 arbitrary units. Vitamin B6 reached the Tmax at 13 h after dosing, the Cmax was 1.4 times higher than the Cbasal, and the AUC was 222 arbitrary units. No differences were observed in Cbasal, Tmax, Cmax and AUC of vitamin A and B6 between control vs. MMT-supplemented cows. Plasma concentrations of vitamins D, E and B1 had no concentration peaks, and were not affected by MMT addition. The lack of a response suggests that their plasma concentration may be tightly regulated. Results of this study do not show evidence that MMT affects the bioavailability of vitamins A and B6 in vivo.

Effect of genetic variants in the SMAD1 and SMAD5 genes promoter on growth and beef quality traits in cattle.

The SMAD1 and SMAD5 genes belong to mothers against decapentaplegic proteins family, which participate in the BMP pathway to control skeletal myogenesis and growth. In the present study, we analyzed the associations between polymorphisms of SMAD1 and SMAD5 genes promoter and important economical traits in Qinchuan cattle. Four SNPs in the SMAD1 gene promoter and three SNPs in the SMAD5 promoter were identified by sequencing of 448 Qinchuan cattles. Allelic and frequency analyses of these SNPs resulted in eight haplotypes both in the promoters of the two genes promoter and identified potential cis-regulatory transcription factor (TF) components. In addition, correlation analysis showed that cattle SMAD1 promoter activity of individuals with Hap4 (P < 0.01) was stronger than that of individuals with Hap2. while the transcriptional activity of individuals with Hap3 within SMAD5 gene promoter was significantly (P < 0.01) higher followed by H2. Uniformly, diplotypes H4-H6 of SMAD1 gene and H1-H3 of SMAD5 gene performed significant (P < 0.01) associations with body measurement and improved carcass quality traits. All these results have indicated that polymorphisms in SMAD1 and SMAD5 genes promoter could impact the transcriptional regulation and then affect muscle content in beef cattle. Moreover, both the SMAD1 and SMAD5 genes were expressed ubiquitously in 10 tissues and had higher expression in the longissimus thoracis tissue from 6-month-old and 12-month-old cattle than in cattle of other ages. We can conclude that SMAD1 and SMAD5 genes may play an important role in muscle growth and development, and the variants mapped within SMAD1 and SMAD5 genes can be utilized in molecular marker-assisted selection for cattle carcass quality and body measurement traits in breed improvement programs of Qinchuan cattle.

Comparative metabolomics analysis of milk components between Italian Mediterranean buffaloes and Chinese Holstein cows based on LC-MS/MS technology.

Buffalo and cow milk have a very different composition in terms of fat, protein, and total solids. For a better knowledge of such a difference, the milk metabolic profiles and characteristics of metabolites was investigated in Italian Mediterranean buffaloes and Chinese Holstein cows were investigated by liquid chromatography tandem-mass spectrometry (LC-MS/MS) in this study. Totally, 23 differential metabolites were identified to be significantly different in the milk from the two species of which 15 were up-regulated and 8 down-regulated in Italian Mediterranean buffaloes. Metabolic pathway analysis revealed that 4 metabolites (choline, acetylcholine, nicotinamide and uric acid) were significantly enriched in glycerophospholipid metabolism, nicotinate and nicotinamide metabolism, glycine, serine and threonine metabolism, as well as purine metabolism. The results provided further insights for a deep understanding of the potential metabolic mechanisms responsible for the different performance of Italian Mediterranean buffaloes' and Chinese Holstein cows' milk. The findings will offer new tools for the improvement and novel directions for the development of dairy industry.

Carcass characteristics and meat evaluation of cattle finished in temperate pasture and supplemented with natural additive containing clove, cashew oil, castor oils, and a microencapsulated blend of eugenol, thymol, and vanillin.

BACKGROUND: Forty crossbred steers were supplemented with different doses (from 0 control to 6000 mg/animal/day) of natural additive blend containing clove essential oil, cashew oil, castor oil, and a microencapsulated blend of eugenol, thymol, and vanillin for 80 days. Carcass characteristics, drip loss, and antioxidant activity were evaluated 24 h post mortem on longissimus thoracis, and the effects of aging (until 14 days) were evaluated for water losses (thawing/aging and cooking), texture, color, and lipid oxidation. RESULTS: The use of the natural additive blend did not modify (P > 0.05) carcass characteristics but did, however, modify body composition (P < 0.05). Drip losses were unaffected by the treatments tested (P > 0.05). There was an observed quadratic effect (P < 0.05) on losses from thawing/aging on the first day of storage. Regarding the effects of natural additives on cooking losses, there was a quadratic effect (P < 0.05) among the treatments on day 7 of aging. Differences between days of aging were only observed with control treatment. Shear force was similar among treatments on days 1 and 7 of aging. On day 14 a linear effect (P < 0.05) was observed. Also, a linear effect (P < 0.05) appeared on meat lightness, meat from the control group being clearer on day 1. No changes were observed in redness among treatments or days of storage (P > 0.05). Yellowness was not modified by the treatments (P > 0.05)but only by the days of storage in control and the lowest dosage used. CONCLUSION: The blend of natural additives has potential use in pasture feeding and could improve meat quality. However, doses should be adjusted. © 2021 Society of Chemical Industry.

The colour and sensory characteristics of longissimus muscle from beef cattle that grazed grass or consumed concentrates prior to slaughter.

BACKGROUND: Grazed grass is an important component of the majority of beef production systems used in temperate climates. Compared to concentrate-fed beef, 'grass-fed' beef can command a premium in some markets based on perceived differences in appearance and sensory characteristics. The influence of grazed grass per se, as well as the duration of grazing, on selected sensory characteristics of beef within a heifer production system was examined. RESULTS: In general, fat from grass-fed cattle was more yellow than fat from similar cattle fed concentrates, whereas muscle from grass-fed cattle was darker than muscle from cattle fed concentrates. At the same carcass weight, muscle from grass-fed cattle had a lower fat concentration than cattle fed concentrates. In the most extreme situation examined, whereby early-maturing heifers were fed concentrates ad libitum from weaning or grazed grass/conserved grass throughout life, until slaughtered at a similar carcass weight (260 kg) and differed in age by 5 months, beef was rated similarly for tenderness and a range of flavours by a trained sensory panel. CONCLUSION: Within the range of beef heifer production systems examined, the sensory characteristics of grass-fed beef do not differ greatly from concentrate-fed beef. © 2021 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Bos taurus haplotypes segregating in Nellore (Bos indicus) cattle.

Brazil is the largest exporter of beef in the world, and most of that beef derives from Nellore cattle. Although considered a zebu breed (Bos indicus), the history of Nellore cattle in Brazil is marked by the importation of bulls from India, the use of a Creole taurine (Bos taurus) maternal lineage to quickly expand the herds and backcrossing to Nellore bulls to recover zebu ancestry. As a consequence, the current Brazilian Nellore population carries an average taurine ancestry of approximately 1%. Although that percentage seems small, some taurine variants deviate substantially from that average, with the better-known cases being the PLAG1-Q haplotype involved with body size variation and the Guarani (PG ) polled variant producing hornless animals. Here, we report taurine haplotypes in 9074 Nellore animals genotyped for 539 657 imputed SNP markers. Apart from PLAG1-Q and PG , our analysis further revealed common taurine haplotypes (>3%) spanning genes related to immunity, growth, reproduction and hair and skin phenotypes. Using data from 22 economically important traits, we showed that many of the major QTL previously reported in the breed are at least partially driven by taurine haplotypes. As B. taurus and B. indicus haplotypes are highly divergent, presenting widely different sets of functional variants, our results provide promising targets for future scrutiny in Nellore cattle.

Feeding fennel (Foeniculum vulgare) seed as a potential appetite stimulant for Holstein dairy calves: Effects on growth performance and health.

This experiment was conducted to determine the effect of increasing dietary doses of fennel seed powder (FSP) on growth performance and health status in calves. Holstein calves (n = 48; 3 d of age; 36.3 ± 1.06 kg BW; mean ± SE) were allocated randomly to diets containing 0 (FSP0), 1.5 (FSP1.5), or 3 g/d (FSP3) FSP in milk (morning feeding; during the first month) and then in the starter feed (top-dressed; from d 31 until weaning on d 71). The calves remained in the trial until d 81. Weight gain and final BW were greater in FSP-supplemented calves compared with control calves. Heart girth and hip width gained more in FSP-supplemented calves compared with control calves. Body weight gain and frame growth were not affected by calf sex. The calves receiving FSP had a lower chance of having elevated rectal temperature (≥39.4°C) and a lower probability of suffering from diarrhea or pneumonia. The chance of having diarrhea, but not pneumonia, was greater in female calves. The chance of medication occurrence for diarrhea and pneumonia was not affected by FSP and calf sex. The FSP3 calves had shorter days with elevated rectal temperature (≥39.4°C) compared with the FSP1.5 (1.2 d; SEM = 0.10) and FSP0 (2.9 d; SEM = 0.10) calves. Days with diarrhea but not its frequency and medication days was shorter (4 d; SEM = 0.10) in the FSP-supplemented calves. Control calves experienced more days with pneumonia compared with calves fed FSP1.5 (3.1 d; SEM = 0.08) and FSP3 (5.4 d; SEM = 0.08). Calves fed FSP3 experienced shorter days (2.3 d; SEM = 0.08) with pneumonia compared with calves fed FSP1.5. Feeding FSP tended to decrease (1.6 d; SEM = 0.10) medication days for pneumonia compared with control group. The duration (2.2 d; SEM = 0.10) and medication days (1.3 d; SEM = 0.15) for diarrhea were higher in female calves compared with the male calves. Compared with the control calves, feeding 3 g/d of FSP may be more beneficial in improving the weight gain and skeletal growth (heart girth and hip width) and in reducing the susceptibility to and duration of diarrhea and pneumonia in dairy calves.

First DNA Sequencing in Beninese Indigenous Cattle Breeds Captures New Milk Protein Variants.

This study investigated polymorphisms in the milk protein genes CSN1S1, CSN2, CSN1S2, CSN3, LALBA, and LGB, and casein haplotypes in Beninese indigenous cattle. Considering 67 animals, DNA sequencing of the genes' exons, flanking regions and parts of the 5'-upstream regions identified 1058 genetic variants including 731 previously unknown. In addition, four novel milk protein variants were detected, including CSN3K (p.Ala66Val), LALBAF (p.Arg58Trp), LGBB1 (p.Ala134Val) and LGBK (p.Thr92Asnfs*13). CSN3K is caused by a novel SNP (BTA6:85656526C>T, exon 4) whereas LALBAF and LGBB1 are due to rs714688595C>T (exon 1) and rs109625649C>T (exon 4), respectively. Regarding LGBK, a frameshift insertion of one adenine residue at BTA11:103257980 (exon 3) induces a premature translation termination resulting in a 46% reduction of the reference protein sequence. The casein polymorphisms formed five main CSN1S1-CSN2-CSN1S2-CSN3 haplotypes including B-A1-A-B, B-A1-A-A and C-A2-A-B which are predominant in the investigated cattle breeds. Moreover, in silico analyses of polymorphisms within the 5'- and 3'- untranslated regions of all six milk proteins revealed effects on microRNA and transcription factor binding sites. This study suggests a large genetic variation of milk protein genes in Beninese cattle, which should be investigated in further studies for their effects on milk production, including quality and yield traits.

Changes in metabolic and hormonal profiles during transition period in dairy cattle - the role of spexin.

BACKGROUND: This study aimed to evaluate spexin as a novel blood marker and to describe the relationship of this peptide with selected biochemical metabolites measured during the transition period in dairy cows. Additionally, mRNA expression of the spexin gene as well as spexin receptors - galanin receptor type 2 and galanin receptor type 3, was investigated in several bovine tissues. Blood samples were collected at weekly intervals starting at 21 days before the estimated parturition day until 21 days in milk to determine concentrations of spexin, nonesterified fatty acids, ß-hydroxybutyrate acid, total and active ghrelin, progesterone, glucose, insulin, IGF-I, triglycerides, cholesterol, leptin, corticosterone and 17-ß-estradiol as well as the activity of aspartate transaminase, alkaline phosphatase and gamma-glutamyl transferase. RESULTS: Spexin concentration decreased from 21 d before parturition to calving day and next it rose during the first 14 d of lactation. The lowest concentration of spexin was recorded on the calving day and it differed from the mean level of this peptide before parturition as well as postpartum. Moreover, differences were observed between mean spexin concentrations before and after calving. Spexin levels were moderately negatively correlated with NEFA (r = - 0.39) and total ghrelin contents (r = - 0.41), weakly correlated with BHBA (r = - 0.35) while they showed a moderate positive relationship with progesterone concentrations (r = 0.42). Moreover, we detected that mRNA expression of GALR2, GALR3 and SPX is present in various bovine tissues (kidney, bowel, rumen, spinal cord, lung, skeletal muscle, liver, heart, fat and spleen). CONCLUSION: A negative correlation between spexin concentration and NEFA, BHBA and total ghrelin contents as well as a positive relationship with levels of progesterone, metabolites and hormones, which are key players in the dairy cow transition period, may confirm an important function of this peptide in metabolism regulation. Thus measurement of spexin concentration could provide useful supplementary information for dairy cow herd health monitoring.