Regulation of the growth performance and the gastrointestinal microbiota community by the addition of defective pear fermentation to feed of small-tailed Han sheep.

This study investigated the effects of defective pear fermentation (DPF) diets on growth performance and gastrointestinal microbial communities in 60 healthy male small-tailed Han sheep, aged 90 days. The sheep were randomly divided into four groups, each consisting of three replicates with five sheep per replicate. Initially, all groups received a basal diet for seven days during the adaptation stage. Subsequently, for 60 days, group C (control) was fed a basal diet, group X received a basal diet with 2% DPF, group Y had a basal diet with 4% DPF, and group Z was fed a basal diet with 6% DPF. The results indicated that group Y experienced a significant increase in average daily gain (ADG) and average daily feed intake (ADFI). The addition of DPF significantly elevated the levels of GSH-Px and notably reduced MDA content compared to group C. Analysis of gastrointestinal microbiota showed that groups receiving DPF had increased relative abundances of Lachnospiraceae_NK3A20_group, norank_f p-2534-18B5_gut_group, Acetitomaculum, Actinobacteriota, Bacteroidota and Ruminococcus_gauvreauii_group, and decreased abundances of Proteobacteria, Prevotella, Staphylococcus, and Psychrobacter compared to group C. Group X exhibited the highest relative abundance of Olsenella, while group Y showed a significant increase in unclassified_f Lachnospiraceae compared to the other groups. Bacterial function prediction indicated that pathways related to energy metabolism were more prevalent in group X and Y. This study preliminarily confirms the feasibility of using DPF as feed additives, providing a foundation for further research and evaluation of DPF's application in animal production.

Effects of Grape Pomace on Growth Performance, Nitrogen Metabolism, Antioxidants, and Microbial Diversity in Angus Bulls.

Polyphenol-rich grape pomace (GP) represents a valuable processing by-product with considerable potential as sustainable livestock feed. This study aimed to investigate the effects of different levels of GP on the growth performance and nitrogen utilization efficiency, antioxidant activity, and rumen and rectum microbiota of Angus bulls. Thirty Angus bulls were allocated three dietary treatments according to a completely randomized design: 0% (G0), 10% (G10), and 20% (G20) corn silage dry matter replaced with dried GP dry matter. The results showed that the average daily gain (ADG) of the G0 group and G10 group was higher than that of the G20 group (p < 0.05); urinary nitrogen levels decreased linearly with the addition of GP (linear, p < 0.05). In terms of antioxidants, the levels of catalase (CAT) in the G10 group were higher than in the G0 and G20 groups (p < 0.05), and the total antioxidative capacity (T-AOC) was significantly higher than that in the G20 group (p < 0.05). In addition, in the analysis of a microbial network diagram, the G10 group had better microbial community complexity and stability. Overall, these findings offer valuable insights into the potential benefits of incorporating GP into the diet of ruminants.

Transcriptomics and metabolomics of blood, urine and ovarian follicular fluid of yak at induced estrus stage.

To gain a deeper understanding of the metabolic differences within and outside the body, as well as changes in transcription levels following estrus in yaks, we conducted transcriptome and metabolome analyses on female yaks in both estrus and non-estrus states. The metabolome analysis identified 114, 13, and 91 distinct metabolites in urine, blood, and follicular fluid, respectively. The Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis highlighted an enrichment of pathways related to amino acid and lipid metabolism across all three body fluids. Our transcriptome analysis revealed 122 differentially expressed genes within microRNA (miRNA) and 640 within long non-coding RNA (lncRNA). Functional enrichment analysis of lncRNA and miRNA indicated their involvement in cell signaling, disease resistance, and immunity pathways. We constructed a regulatory network composed of 10 lncRNAs, 4 miRNAs, and 30 mRNAs, based on the targeted regulation relationships of the differentially expressed genes. In conclusion, the accumulation of metabolites such as amino acids, steroids, and organic acids, along with the expression changes of key genes like miR-129 during yak estrus, provide initial insights into the estrus mechanism in yaks.

Effect of Potato Vine and Leaf Mixed Silage Compared to Whole Corn Crops on Growth Performance, Apparent Digestibility, and Serum Biochemical Characteristics of Fattening Angus Bull.

This study aims to explore the different growth performances of the Angus bull on potato vine and leaf mixed silage in the early fattening period and to provide a reference animal production trial. Thirty-six 13-month-old Angus bulls were divided into three groups with 403.22 ± 38.97 kg initial body weight and fed with three different silage diets: (1) control: whole-plant corn silage as control (CS); (2) treatment 1: 50% whole-plant corn +50% potato vine and leaf silage (PVS1); and (3) treatment 2: 75% potato vine and leaf +15% rice straw +10% cornmeal silage (PVS2). After the 14 days pre-feeding, the formal experiment was carried out for 89 days. The result showed that the ash content of the potato vine and leaf mixed silage (PVS) in the treatment groups was higher than that in control group, and the ash content of PVS1 and PVS2 even reached 10.42% and 18.48% (DM%), respectively, which was much higher than that of the CS group at 4.94%. The crude protein content in silage also increased with the additional amount of potato vine and leaf. The apparent crude protein digestibility of the PVS groups was also significantly higher than that of the CS group (p < 0.05). In terms of serum biochemical indexes, blood urea nitrogen (BUN) in the experimental groups was significantly higher than in the control group (p < 0.05). Compared with PVS2, cholesterol (CHO) was significantly lower in the CS and PVS1 groups (p < 0.05). Moreover, the high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) of PVS2 were significantly higher than those of the CS and PVS1 group (p < 0.05), and daily gain (ADG) as a key production index had a significantly negative correlation with the CHO (r = -0.38, p < 0.05) and HDL-C (r = -0.40, p < 0.05) of cattle. In conclusion, PVS had higher crude protein content and ash but less starch than whole-corn silage. The PVS could replace whole-plant corn silage at the same dry matter status and did not affect the weight gain in this trial.

2-Hydroxy-4-(Methylthio) Butanoic Acid Isopropyl Ester Supplementation Altered Ruminal and Cecal Bacterial Composition and Improved Growth Performance of Finishing Beef Cattle.

The objective of this study was to evaluate the effects of isopropyl ester of 2-hydroxy-4-(methylthio)-butyrate acid (HMBi) on ruminal and cecal fermentation, microbial composition, nutrient digestibility, plasma biochemical parameters, and growth performance in finishing beef cattle. The experiment was conducted for 120 days by a complete randomized block design. Sixty 24-month-old Angus steers (723.9 ± 11.6 kg) were randomly assigned to one of the flowing three treatments: basal diet (the concentrate: 7.6 kg/head·d-1, the rice straw: ad libitum) supplemented with 0 g/d MetaSmart® (H0), a basal diet supplemented with 15 g/d of MetaSmart® (H15), and a basal diet supplemented with 30 g/d of MetaSmart® (H30). Results showed that the average daily gain (ADG) increased linearly (P = 0.004) and the feed conversion ratio (FCR) decreased linearly (P < 0.01) with the increasing HMBi supplementation. Blood urea nitrogen (BUN) concentration significantly decreased in the H30 group (P < 0.05) compared with H0 or H15. The ruminal pH value tended to increase linearly (P = 0.086) on day 56 with the increased HMBi supplementation. The concentrations of ammonia-nitrogen (NH3-N), propionate, isobutyrate, butyrate, isovalerate, valerate, and total volatile fatty acid (VFA) were linearly decreased in the cecum (P < 0.05). The results of Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) showed that the abundance of most pathways with a significant difference was higher in the rumen and lower in the cecum in the H30 group compared to the H0 group, and those pathways were mainly related to the metabolism of amino acids, carbohydrates, and lipids. Correlation analysis showed that ADG was positively associated with the ratio of firmicutes/bacteroidetes both in the rumen and cecum. Additionally, the abundance of Lachnospiraceae, Saccharofermentans, Lachnospiraceae_XPB1014_group, and Ruminococcus_1 was positively correlated with ADG and negatively correlated with FCR and BUN in the rumen. In the cecum, ADG was positively correlated with the abundances of Peptostreptococcaceae, Romboutsia, Ruminococcaceae_UCG-013, and Paeniclostridium, and negatively correlated with the abundances of Bacteroidaceae and Bacteroides. Overall, these results indicated that dietary supplementation of HMBi can improve the growth performance and the feed efficiency of finishing beef cattle by potentially changing bacterial community and fermentation patterns of rumen and cecum.

Serum Biochemical Parameters, Rumen Fermentation, and Rumen Bacterial Communities Are Partly Driven by the Breed and Sex of Cattle When Fed High-Grain Diet.

Hybridization in bovines is practiced with the main aim of improving production performance, which may imply the microbial variations in the rumen from the parental breed cross to their progeny. Besides, the interactions of offspring breed with sex in terms of rumen bacteria are not clear. This study aims to evaluate the variations in rumen bacterial communities in different breeds and sexes, and the correlations among fattening performance, serum biochemical parameters, and rumen fermentation. Forty-two 19.2 ± 0.67-month-old beef cattle (390 ± 95 kg of initial body weight) comprising two genetic lines (Yiling and Angus × Yiling) and two sexes (heifers and steers) were raised under the same high-grain diet for 120 d. On the last two days, blood samples were collected from each animal via the jugular vein before morning feeding for analyzing serum biochemical parameters; rumen fluid samples were obtained via esophageal intubation 2 h after morning feeding for analyzing rumen fermentation parameters and bacterial communities. The results show that both breed and sex had a certain impact on fattening performance, serum biochemical parameters, and rumen fermentation. No differences in the diversity and structure of rumen bacterial communities were observed. Significant interactions (p < 0.05) of breed and sex were observed for Succinivibrionaceae UCG-002 and Prevotellaceae UCG-001. The relative abundances of the Rikenellaceae RC9 gut group, Prevotellaceae UCG-003, and Succinivibrio were different (p < 0.05) between breeds. Heifers had a higher (p = 0.008) relative abundance of the Rikenellaceae RC9 gut group than steers. Correlation analysis showed a significant relationship (p < 0.05) of rumen bacteria with serum biochemical parameters, rumen pH, and rumen fermentation patterns. Additionally, only two genera, Prevotellaceae UCG-003 and Prevotellaceae UCG-001, had positive correlations with feed efficiency. In conclusion, serum biochemical parameters, rumen fermentation, and rumen bacterial communities are partly driven by the breed and sex of cattle fed a high-grain diet.

Effects of compound probiotics on growth performance, rumen fermentation, blood parameters, and health status of neonatal Holstein calves.

This study aimed to investigate the effects of compound probiotics (consisting of 108 cfu/g of Lactobacillus plantarum, 108 cfu/g of Pediococcus acidilactici, 108 cfu/g of Pediococcus pentosaceus, 107 cfu/g of and Bacillus subtilis) on growth performance, rumen fermentation, bacteria community, blood parameters, and health status of Holstein calves at the first 3 mo of age. Forty-eight newborn calves were randomly divided into the following 3 groups: control group (milk replacer with no compound probiotics), low compound probiotics group (milk replacer + 0.12 g of compound probiotics per head per day), and high compound probiotics group (HP; milk replacer + 1.2 g of compound probiotics per head per day). Starter pellets of the low compound probiotics and HP groups were coated with 0.05% compound probiotics. Milk replacer was provided from 2 to 63 d of age (6 L at 2-10 d, 8 L at 11-42 d, 6 L at 43-49 d, 4 L at 50-56 d, and 2 L at 57-63 d), and starter pellets were provided ad libitum from 7 to 90 d of age. Body weight and body size (d 1, 30, 60, and 90), blood (d 40 and 80), and rumen fluid (d 90) were analyzed using the one-way ANOVA procedure; fecal score was recorded daily and analyzed as repeated measures using the mixed model procedure. Results showed that diet supplemented with compound probiotics had no effects on the body weight, average daily gain, dry matter intake, and feed efficiency. At 90 d of age, diet supplemented with compound probiotics decreased the withers height. Immunity activities increased in the HP group, supported by the increased concentrations of serum total protein and immunoglobulins at 40 d of age, and by the increased activity of superoxide dismutase at 80 d of age. Diet supplemented with compound probiotics altered rumen fermentation, indicated by the decreased rumen acetic acid and propionic acid, and the increased butyric acid concentrations. Diet supplemented with compound probiotics improved the health status of calves, indicated by the decreased fecal score at 3 wk of age and the decreased medicine treatments. In summary, although diet supplemented with HP decreased the withers height, this level of probiotics is recommended to improve rumen development and health status of newborn Holstein calves.

Rumen Fermentation Characteristics Require More Time to Stabilize When Diet Shifts.

This study was conducted to explore the proper time required to achieve stabilization in digestibility, serum metabolism, and rumen fermentation characteristics when different diets shift, thus providing decision-making of practical sampling frequency for basal nutritional research. For these purposes, 12 Holstein steers (body weight 467 ± 34 kg, age 14 ± 0.5 months) were equally assigned to two dietary treatments: high-density (metabolizable energy (ME) = 2.53 Mcal/kg and crude protein (CP) = 119 g/kg; both ME and CP were expressed on a dry matter basis) or low-density (ME = 2.35 Mcal/kg and CP = 105 g/kg). The samples of feces, serum, and rumen contents were collected with a 30-day interval. All data involved in this study were analyzed using the repeated measures in mixed model of SPSS. Results showed that nutrient apparent digestibility and serum metabolic parameters were stable across each monthly collection, while most rumen fermentation characteristics, namely concentrations of acetate, propionate, isobutyrate, and valerate, were affected by the interaction effects between collection period and dietary density. These findings indicate that rumen fermentation characteristics require more time to stabilize when diet shifts. It is recommended to collect ruminal digesta monthly to evaluate rumen fermentation characteristics, while unnecessary to sample monthly for digestion trials and blood tests in the long-term fattening of Holstein steers. This study may provide insights into exploring the associations between detected parameters and stabilization time, and between diet type and stabilization time when diet shifts.

Effects of Age and Rice Straw Inclusion Levels in the Diet of Yiling Cull Cows on Growth Performance, Meat Quality, and Antioxidant Status of Tissues.

The objectives of this study were to investigate the effects of age and dietary straw levels on growth performance, carcass and meat traits, as well as tissue antioxidant status of Yiling cull cows. Twenty-four Yiling cull cows were arranged in a 2 × 2 factorial design: two age classes consisting of younger cull cows (YCC; appearing with three or four pairs of permanent teeth) and older cull cows (OCC; worn out teeth); two dietary treatments consisting of lower and higher rice straw levels (LRS and HRS; providing 0.7 kg/d and 1.2 kg/d rice straw per head based on air-dry basis, respectively). Cows were fed twice a day. Straw was offered at half of the predetermined weight each meal; concentrate was separately supplied ad libitum. After 300 d of feeding, final body weight (BW), total BW gain, average daily gain and gain:feed intake were higher (p < 0.01) in the YCC group than in the OCC group. Total dry matter intake was higher (p = 0.03) in the HRS group than in the LRS group, but neutral detergent fiber apparent digestibility was negatively affected (p = 0.01) by increased straw levels. Decreased C15:0, C17:0, C20:5n3c, and saturated fatty acids (SFAs) proportion as well as increased C18:1n9c and monounsaturated fatty acids (MUFAs) proportion in meat from YCC with HRS diet were observed as compared to that in meat from YCC with LRS diet (p < 0.05). Meat from HRS group had higher (p = 0.04) C18:3n3c proportion than meat from LRS group. No significant differences (p > 0.05) were found for meat quality attributes except for cooking loss, which was higher (p = 0.02) in the HRS group than in the LRS group. Both YCC group and HRS group had higher (p < 0.05) cold carcass weight compared to OCC group and LRS group. Moreover, catalase activity of liver tissue was higher (p = 0.045) in YCC than in OCC, while superoxide dismutase activity of muscle tissue was higher (p = 0.01) in LRS than in HRS. Based on results, we concluded that younger age and feeding high-level straw can improve the finishing performance of Yiling cull cows.

1H NMR-based water-soluble lower molecule characterization and fatty acid composition of Chinese native chickens and commercial broiler.

The aim of this study was to compare the water-soluble low molecular weight (WLMW) compounds and fatty acids (FAs) in raw meat and chicken soup between the two Chinese native chickens (Wuding chicken and Yanjin silky fowl chicken) and one typical commercial broiler (Cobb chicken). The WLMW compounds of chicken meat was studied using 1H nuclear magnetic resonance spectroscopy (1H NMR) and the FAs were identified and quantified using gas chromatography-mass spectrometry (GC-MS). Compared with typical commercial broiler, the main flavor substances (WLMW compounds and FAs) content were significantly higher in the breast and leg meat of the two Chinese native chickens (P < 0.05). Instead, the content of main flavor compounds was significantly higher in chicken soup of typical commercial broiler (P < 0.05). These results contribute to a further understanding the distinction of the flavor compounds between the typical commercial broiler and Chinese native chickens, which could be used to help assess the meat quality of different local broilers.

The clinical and imaging features of cerebrotendinous xanthomatosis: A case report and review of the literature.

RATIONALE: Cerebrotendinous xanthomatosis (CTX) is a rare autosomal recessive lipid deposition disorder characterized by systemic signs and neurological dysfunction. The radiological features of CTX are infrequently summarized in the literature. PATIENT CONCERNS: We described a 40-year-old male patient who repeatedly engaged in wrestling matches and presented with progressive difficulty in walking and reduced balance with egg-sized, hard, smooth, and painless masses in both ankles. DIAGNOSIS: Neuroimaging examination showed abnormalities both supra- and infratentorially. Bilateral ankle joint magnetic resonance imaging showed bilateral xanthomata of the Achilles tendon. The diagnosis was confirmed by the detection of a sterol 27-hydroxylase gene mutation. INTERVENTIONS: The patient was treated with chenodeoxycholic acid (250 mg 3 times per day). OUTCOMES: To date, the patient's bilateral xanthomas of the Achilles tendon have begun to diminish, and his neurological impairment has not deteriorated further but has not yet improved. LESSONS: We report a rare case of CTX and summarize the clinical and imaging features of this disease. Our findings suggest that the abnormal signals in the dentate nucleus or a long spinal cord lesion involving the central and posterior cord, combined with tendon xanthoma, are important clues for the diagnosis of CTX.

Effects of dietary energy on antioxidant capacity, glucose-lipid metabolism and meat fatty acid profile of Holstein bulls at different ages.

This experiment was conducted to investigate the effects of dietary energy on antioxidant capacity, liver glucose-lipid-related gene expressions and meat fatty acid of Holstein bulls. Thirty-six Holstein bulls (age, 17.0 ± 0.49 months; body weight, 493.3 ± 39.7 kg) were randomly allocated to three dietary treatments. The metabolizable energy of diets was 10.12, 10.90 and 11.68 MJ/kg. Bulls in each dietary treatment were sampled at the age of 20, 23 or 26 months. Results showed that serum glutathione peroxidase and superoxide dismutase decreased with the increasing age. Dietary energy and age had interaction effects on the expressions of fatty acid synthase, peroxisome proliferator-activated receptor alpha, acyl coenzyme A oxidase 1 and carnitine palmitoyl-transferase 1 alpha. Besides, the increase of age and dietary energy increased the expression of liver phosphoenolpyruvate carboxykinase 1. The expressions of liver glucose-6-phosphatase, tumour necrosis factor alpha and sterol regulatory element binding protein 1 increased with the increasing age. The increase of age and dietary energy increased the proportions of C18:1cis-9, C18:2n-6trans and monounsaturated fatty acid. In summary, the increase of age and dietary energy enhanced the intensity of metabolic changes and inflammatory responses. Dietary energy and age affected the expressions of liver lipid metabolism-related genes, further affected meat fatty acid composition of Holstein bulls.

Preferentially Disrupted Core Hubs Within the Default-Mode Network in Patients With End-Stage Renal Disease: A Resting-State Functional Magnetic Resonance Imaging Study.

Neuroimaging evidence implies that cognitive impairment in patients with end-stage renal disease (ESRD) is related to the disruption of the default-mode network (DMN). The DMN can be divided into three functionally independent subsystems, which include the cortical hub subsystem [consisting of the posterior cingulate cortex (PCC) and the anterior medial prefrontal cortex (aMPFC)], the dorsal medial prefrontal cortex (dMPFC) subsystem, and the medial temporal lobe (MTL) subsystem. However, it is unknown how the functional connectivity (FC) in DMN subsystems is differentially impaired in ESRD. This prospective study was carried out at the Affiliated Hospital of Qingdao University, China, between August 2018 and July 2020. Thirty-two ESRD patients and forty-five healthy controls (HCs) were recruited for this study and received resting-state functional magnetic resonance imaging (rs-fMRI) scanning, and FCs on predefined regions of interest (ROIs) were individually calculated in three DMN subsystems using both ROI- and seed-based FC analyses to examine FC alterations within and between DMN subsystems. The two-sample t-test was used for the comparisons between groups. We also tested the associations between FC changes and clinical information using Pearson's correlation analysis. The results demonstrated that ESRD patients, compared with HCs, exhibit reduced FC specifically within the cortical hubs and between the DMN hubs and two subsystems (the dMPFC and MTL subsystems). Moreover, the FC values between the aMPFC and PCC were positively correlated with creatinine and urea levels in the ESRD patients. Our results suggest that the cortical hubs (PCC and aMPFC) are preferentially disrupted and that other subsystems may be progressively damaged to a certain degree as the disease develops.

Chopping Roughage Length Improved Rumen Development of Weaned Calves as Revealed by Rumen Fermentation and Bacterial Community.

Roughage particle size can influence rumen development, which is also determined by rumen microorganisms and their metabolic end-products. Therefore, the aim of this study was to evaluate the comprehensive effects of roughage length and rumen bacterial community on the rumen development of weaned calves. A total of thirty-six weaned Angus female calves (125 ± 3 d; 161.2 ± 13.0 kg) were randomly assigned to three diets differing in roughage particle size: 4 cm (short length); 24 cm (medium length); and 44 cm (long length). Results showed that chopping roughage increased dry matter intake and organic matter apparent digestibility; altered rumen fermentation indicated by the increased rumen butyrate and valerate concentrations; and increased plasma glucose, cholesterol, and total protein. Chopping roughage affected rumen bacterial community, as indicated by altering the diversity indices; by increasing ruminal bacteria Papillibacter and Eubacterium_hallii_group, which are involved in butyrate production; and by increasing Synergistetes and Mogibacterium, which are involved in bacterial colonization. In conclusion, chopping roughage at 4 cm was shown to improve the rumen bacterial community, alter rumen fermentation, eventually promote the development of rumen.

Multimodal MR Features of 8 Cases of Epithelioid Glioblastoma.

PURPOSE: The MRI features of epithelioid glioblastoma (eGBM) were analyzed. The apparent diffusion coefficient (ADC), MR perfusion-weighted imaging (PWI), and magnetic resonance spectroscopy (MRS) findings were quantitatively analyzed. METHODS: The MRI images of 8 cases of eGBM were analyzed retrospectively. The location and edge, signal, peritumoral edema, adjacent meningeal invasion, and enhancement of the lesions were observed. The ADC value, relative cerebral blood volume (rCBV), relative cerebral blood flow (rCBF), and N-acetylaspartate/acetylcholine (NAA/Cho) value were analyzed. RESULTS: Among the 8 patients, the tumors were mainly located in the temporal lobe (n = 3), frontal lobe (n = 3), and parietal lobe (n = 2). The lesion boundary was clear in 6 cases and unclear in 2. The lesions were superficial in 5 cases and in the deep white matter in 3. Internal hemorrhage was observed in 4 cases. There was cystic necrosis in 7 cases, and only 1 case was solid without cystic necrosis. There was no edema around the lesion in 1 case, severe edema in 5, and moderate edema in 2. In 4 cases, the adjacent meninges were involved, and in 1 case, the ependyma was involved. Two patients developed leptomeningeal metastasis within 2 months after the operation. The average ADC value of the tumor parenchyma among all 8 patients was7.15 × 10-4 mm2/s,which was 17.6% lower than that of the contralateral side. The Cho/NAA metabolite ratio was 5.27 and 0.81 in the lesions of 2 patients. The rCBV was 3.51 ml/100 g and 3.32 ml/100 g of lesions in 2 patients; these values were 36% and 29% higher, respectively, than those of the contralateral side. The rCBF was 31.5 ml/100 g/min and 82.1 ml/100 g/min of lesions in two patients; these values were 49% and 203% higher, respectively, than those of the contralateral side. CONCLUSION: eGBM characteristics include a superficial location, easy cyst degeneration, easy necrosis and hemorrhage, and clear boundaries. It easily invades adjacent meninges and shows cerebrospinal fluid dissemination and metastasis. Combining new MR techniques, such as ADC values, PWI, and MRS, could be helpful for improving diagnostic accuracy.

High-density diet improves growth performance and beef yield but affects negatively on serum metabolism and visceral morphology of Holstein steers.

The objective of this study was to evaluate the effect of different dietary densities on growth performance, carcass characteristics, meat quality, serum metabolism, ruminal papillae morphology and liver injuries of steers. For this purpose, a total of eighteen Holstein steers were randomly fed one of the three diets: high energy and protein diet (H), standard energy and protein diet (C), and low energy and protein diet (L) for 11 months fattening with three-step finishing strategy. Steers fed with H diet had higher (p < .05) average daily gain, feed efficiency, hot carcass weight, serum aspartate aminotransferase to alanine aminotransferase ratio, and monounsaturated fatty acids along with continuous low ruminal pH value, severer hepatic steatosis and ruminal papillae parakeratosis. Meanwhile, steers fed L diet increased the proportion of C20:0, C22:6n-3, saturated fatty acids and n-3 polyunsaturated fatty acids along with lower n-6 to n-3 ratio in longissimus dorsi muscle as compared to that of steers fed H diet. Dietary densities did not influence (p > .10) proximate nutrients and sensory characteristics of beef. The present study indicates that Holstein steers could achieve better growth and carcass performance under high-density diet, whereas they are under threat of visceral injuries and metabolic disorders. This study gives comprehensive relationship between productivity and animal health and suggests that a proper diet should be adopted for fattening Holstein steers in consideration of both beef quality and quantity and animal health.

Digestive Ability, Physiological Characteristics, and Rumen Bacterial Community of Holstein Finishing Steers in Response to Three Nutrient Density Diets as Fattening Phases Advanced.

The aim of this study is to track the dynamic alterations in nutrient intake and digestion, rumen fermentation and plasma metabolic characteristics, and rumen bacterial community of Holstein finishing steers in response to three nutrient density diets as fattening phases advanced. A total of eighteen Holstein steers were randomly allocated into three nutrient density groups and steers in each group were fed under a three-phase fattening strategy, with nutrient density increased in each group when fattening phase advanced. Results showed that both fattening phase and dietary nutrient density significantly influenced the nutrient digestion, most of the rumen fermentation parameters, and part of bacteria at phylum and genus levels. Individually, dietary nutrient density affected the concentrations of plasma alanine aminotransferase and urea N, bacterial richness and evenness. All determined nutrient intake and plasma biochemical parameters, except for alanine aminotransferase and triglyceride, differed among fattening phases. Spearman correlation analysis revealed strong correlations between fiber intake and bacterial richness and evenness, rumen fermentation characteristics and certain bacteria. Moreover, Patescibacteria abundance was positively correlated with ambient temperature and plasma total protein. These results indicate that rumen fermentation and nutrient digestion were influenced by both dietary nutrient density and fattening phase, and these influences were regulated by certain rumen bacterial community and ruminal bacteria may be affected simultaneously by ambient temperature. This study may provide insights into diet optimization and potentially adaptive mechanism of rumen bacterial community in response to fattening phases and gradually climatic change.

Functional adaptation rather than ecogeographical rules determine body-size metrics along a thermal cline with elevation in the Chinese pygmy dormouse (Typhlomys cinereus).

Phenotypic plasticity is crucial for how organisms respond to variation in their environment, affecting their diversity and distribution, especially in the light of rapid environmental change. Ecogeographical rules predict an association between specific adaptive morphological and physiological traits with cooler conditions due to higher latitude, elevation, or climate change. Such ecogeographical effects are often most evident in ancient species due to continuous selective adaptation occurring over long periods of time. Here, we use the suitably ancient Chinese pygmy dormouse (Typhlomys cinereus) to test whether body-size, appendage length and heart size vary in accordance with Bergmann's, Allen's and Hesse's rule, respectively. Based on a sample of 67 adult individuals (female, n = 29; male n = 38) trapped at 37 sites transcending an elevational range from 414 to 1757 m, we tested for trait concordance with Bergmann's rule (body mass, length and SMI), Allen's rule (length of tail, foot, ear, snout), and Hesse's rule (wet and dry heart mass). Effects of elevation (and thus temperature lapse rate; calculated as 0.61 °C per 100 m) on body size, appendage length and heart size, were tested by fitting Standardized Major Axis (SMA) models. We observed substantial heterogeneity in morphometric traits allowing for the detection of ecogeographical clines. However, none conformed with Bergmann's, Allen's (except ear size), or Hesse's rule. However, our results indicate some support for Geist's rule of net primary productivity. We conclude that pervasive functional life-history adaptations in this blind, arboreal, echolocating ancient species exceeded selection for morphological energy efficiency constraints, with the notable exception of reduced ear pinnae size at colder, elevated sites. This is an important consideration for predicting how species, and populations in general, may adapt to human induced rapid environmental change, contrary to expectations of warming driving selection for smaller body-size.

Effects of Dietary Energy on Growth Performance, Rumen Fermentation and Bacterial Community, and Meat Quality of Holstein-Friesians Bulls Slaughtered at Different Ages.

The objective of this study was to evaluate the effects of dietary energy levels on growth performance, rumen fermentation and bacterial community, and meat quality of Holstein-Friesians bulls slaughtered at different ages. Thirty-six Holstein-Friesians bulls (17 months of age) were divided into a 3 × 3 factorial experiment with three energy levels (LE, ME and HE; metabolizable energy is 10.12, 10.90 and 11.68 MJ/kg, respectively) of diets, and three slaughter ages (20, 23 and 26 months). Results indicated that bulls fed with ME and HE diets had higher dry matter intake, average daily gain, and dressing percentage at 23 or 26 months of age. The ME and HE diets also reduced bacterial diversity, altered relative abundances of bacteria and produced lower concentrations of acetate, but higher butyrate and valerate concentrations in rumen fluid. Increasing in dietary energy and slaughter age increased the intramuscular fat (IMF) and water holding capacity. In summary, Holstein-Friesians bulls fed with ME and HE diets, slaughtered at 23 and 26 months of age could be a good choice to produce beef with high IMF. Slaughter age may have less influence than dietary energy in altering fermentation by increasing amylolytic bacteria and decreasing cellulolytic bacteria, and thus, further affecting meat quality.