Effect of Acacia albida Leaf Supplementation on Reproductive Parameters and Pre-Weaning Growth of Arabian Lambs

A trial on Acacia albida leaf supplementation on reproductive parameters and pre-weaning growth of Arabian lambs was conducted from September 2020 to May 2021 at the small ruminant station of the Livestock Research Institute for Development (IRED) in N’Djamena, Chad. Forty-eight (48) Arabian sheep (45 non-pregnant females and 3 males for a sex ratio of 1 ram to 15 ewes) with an average weight of 20.3 ± 1.2 kg and aged approximately 2 years were divided into 3 groups of 15 ewes each. The supplemented group received in addition to the dominant forage of the pasture (300 g of Dactyloctenium aegyptium + 300 g of Cenchrus ciliaris + 600 g of Panicum maximum), 400 g and 600 g of Acacia albida leaves/animal/day while the control group received only 300 g of Dactyloctenium aegyptium + 300 g of Cenchrus ciliaris + 600 g of Panicum maximum. From the results of this study, it appears that the ewes that received 400 g of Acacia albida leaves had a significantly higher fertility rate and birth mortality rate (93.03% and 6.25% respectively). Animals in the control group had a significantly higher pre-weaning mortality rate than those receiving Acacia albida leaves as a supplement (16.66% versus 6.66% and 14.28% respectively). The highest weight of the lambs was observed in the ration supplemented with 600 g of Acacia albida leaves (12209.66 g). The total weight gain, as well as the average daily weight gain of the lambs receiving the 600 g Acacia albida leaf ration was significantly higher than those of the other rations. Supplementation with 400 g and 600 g of Acacia albida leaves can be recommended as a protein supplement for breeding ewes and pre-weaned lambs.

Clonidine use during dexmedetomidine weaning:A systematic review

BACKGROUND Dexmedetomidine is a centrally acting alpha-2A adrenergic agonist that is commonly used as a sedative and anxiolytic in the intensive care unit(ICU),with prolonged use increasing risk of withdrawal symptoms upon sudden discontinuation.As clonidine is an enterally available alpha-2A adrenergic agonist,it may be a suitable agent to taper off dexmedetomidine and reduce withdrawal syndromes.The appropriate dosing and conversion strategies for using enteral clonidine in this context are not known.The objective of this systematic review is to summarize the evidence of enteral clonidine application during dexmedetomidine weaning for prevention of withdrawal symptoms.AIM To systematically review the practice,dosing schema,and outcomes of enteral clonidine use during dexmedetomidine weaning in critically ill adults.METHODS This was a systematic review of enteral clonidine used during dexmedetomidine weaning in critically ill adults(≥18 years).Randomized controlled trials,prospective cohorts,and retrospective cohorts evaluating the use of clonidine to wean patients from dexmedetomidine in the critically ill were included.The primary outcomes of interest were dosing and titration schema of enteral clonidine and dexmedetomidine and risk factors for dexmedetomidine withdrawal.Other secondary outcomes included prevalence of adverse events associated with enteral clonidine use,re-initiation of dexmedetomidine,duration of mechanical ventilation,and ICU length of stay.RESULTS A total of 3427 studies were screened for inclusion with three meeting inclusion criteria with a total of 88 patients.All three studies were observational,two being prospective and one retrospective.In all included studies,the choice to start enteral clonidine to wean off dexmedetomidine was made at the discretion of the physician.Weaning time ranged from 13 to 167 h on average.Enteral clonidine was started in the prospective studies in a similar protocolized method,with 0.3 mg every 6 h.After starting clonidine,patients remained on dexmedetomidine for a median of 1-28 h.Following the termination of dexmedetomidine,two trials tapered enteral clonidine by increasing the interval every 24 h from 6 h to 8h,12h,and 24 h,followed by clonidine discontinuation.For indicators of enteral clonidine withdrawal,the previously tolerable dosage was reinstated for several days before resuming the taper on the same protocol.The adverse events associated with enteral clonidine use were higher than patients on dexmedetomidine taper alone with increased agitation.The re-initiation of dexmedetomidine was not documented in any study.Only 17(37%)patients were mechanically ventilated with median duration of 3.5 d for 13 patients in one of the 2 studies.ICU lengths of stay were similar.CONCLUSION Enteral clonidine is a strategy to wean critically ill patients from dexmedetomidine.There is an association of increased withdrawal symptoms and agitation with the use of a clonidine taper.

The dynamics of the piglet gut microbiome during the weaning transition in association with health and nutrition

Background: Understanding the composition of the microbial community and its functional capacity during weaning is important for pig production as bacteria play important roles in the pig's health and growth performance. However,limited information is available regarding the composition and function of the gut microbiome of piglets in early-life.Therefore, we performed 16 S rRNA gene and whole metagenome shotgun sequencing of DNA from fecal samples from healthy piglets during weaning to measure microbiome shifts, and to identify the potential contribution of the early-life microbiota in shaping piglet health with a focus on microbial stress responses, carbohydrate and amino acid metabolism.Results: The analysis of 16 S rR NA genes and whole metagenome shotgun sequencing revealed significant compositional and functional differences between the fecal microbiome in nursing and weaned piglets. The fecal microbiome of the nursing piglets showed higher relative abundance of bacteria in the genus Bacteroides with abundant gene families related to the utilization of lactose and galactose. Prevotel a and Lactobacil us were enriched in weaned piglets with an enrichment for the gene families associated with carbohydrate and amino acid metabolism. In addition, an analysis of the functional capacity of the fecal microbiome showed higher abundances of genes associated with heat shock and oxidative stress in the metagenome of weaned piglets compared to nursing piglets.Conclusions: Overal, our data show that microbial shifts and changes in functional capacities of the piglet fecal microbiome resulted in potential reductions in the effects of stress, including dietary changes that occur during weaning.These results provide us with new insights into the piglet gut microbiome that contributes to the growth of the animal.

Change of BMD after Weaning or Resumption of Menstruation in Chinese Women with Different FokI VDR-genotypes:A Randomized,Placebo-controlled,Calcium Supplementation Trial

Objective To investigate the effect of calcium supplementation on bone mineral density （BMD） in Chinese women with different Fokl vitamin D receptor （VDR） genotypes （FF, Ff, and ff） after weaning or resumption of menstruation during lactation. Methods A total of 40 subjects with the same Fokl VDR genotype were randomly divided into two groups： one received calcium tablet （600 mg once daily as CaCO3） and the other placebo tablet once daily for 1 year. At baseline, BMD was measured by dual-energy X-ray absorptiometry at lumbar spine （L2-L4） and at left hip whereas serum PICP, serum OC, and urinary CTX, serum 25（OH）VitD3, and serum estradiol were measured at weaning and I year thereafter. Results After the intervention, BMD at lumbar spine and at left hip increased significantly in all these women with a trend among different Fokl VDR genotypes such as FF 〉 Ff 〉 ff （P〈O.05, 〈0.01, and 〈0.001, respectively）. BMD at lumbar spine in women with FF VDR genotype increased much more rapidly than in those with ff VDR genotype （P〈0.05）. Compared with the control group women with the FF genotype regained more BMD after calcium supplementation （P〈0.05）. Conclusion Daily calcium 600 mg supplementation has beneficial effect on the bone health of women with FF VDR genotype.

Weaning methods affect ruminal methanogenic archaea composition and diversity in Holstein calves

The objective of the present study was to examine the effect of different weaning methods on the ruminal methanogenic archaea composition and diversity in Holstein calves.Thirty-six newborn Holstein bull calves were assigned to 1 of 3 treatments:(1)conventional weaning(d 56)and fed a high proportion of solid feed(CWS);(2)conventional weaning(d 56)and fed a high proportion of liquid feed(CWL);(3)early weaning(d 42)and fed with a high proportion of solid feed(EWS).High-throughput sequencing of the methyl coenzyme M reductase(mcr A)gene,which encodes theα-subunit of methyl coenzyme M reductase-the enzyme that catalyzes the final step in methanogenesis was used to determine the composition and diversity of rumen methanogens.No significant difference(P>0.05)was observed for operational taxonomic units(OTUs)or richness indices,but diversity indices increased(P<0.05)for calves fed high dietary solids.Predominant families across the three treatments were Methanobacteriaceae,Thermoplasmataceae and Methanomassiliicoccaceae.Calves in the EWS treatment had a higher(P<0.05)relative abundance of Methanobrevibacter sp.strain AbM4 and Methanosphaera stadtmanae,while calves in the CWL treatment had a higher(P<0.05)abundance of Methanosphaera sp.strain SM9.A positive(P<0.05)relationship was identified between butyrate and Methanobrevibacter sp.strain AbM4.In conclusion,the composition and diversity of methanogens in the rumen of Holstein calves varied under the different weaning methods.This study identified a positive relationship between butyrate and Methanobrevibacter sp.strain AbM4,potentially reflecting correlations between ruminal fermentation variables and methanogenesis function.These in-depth analyses provide further understanding of weaning methods for intensified production systems.

Acrylamide neurotoxicity on the cerebrum of weaning rats

The mechanism underlying acrylamide-induced neurotoxicity remains controversial. Previous studies have focused on acrylamide-induced toxicity in adult rodents, but neurotoxicity in weaning rats has not been investigated. To explore the neurotoxic effect of acrylamide on the developing brain, weaning rats were gavaged with 0, 5, 15, and 30 mg/kg acrylamide for 4 consecutive weeks. No obvious neurotoxicity was observed in weaning rats in the low-dose acrylamide group （5 mg/kg）. However, rats from the moderateand high-dose acrylamide groups （15 and 30 mg/kg） had an abnormal gait. Furthermore, biochemical tests in these rats demonstrated that glutamate concentration was significantly reduced, and ^-aminobutyric acid content was significantly increased and was dependent on acrylamide dose. Immunohis- tochemical staining showed that in the cerebral cortex, γ-aminobutyric acid, glutamic acid decarboxylase and glial fibrillary acidic protein expression increased remarkably in the moderate- and high-dose acrylamide groups. These results indicate that in weaning rats, acrylamide is positively associated with neurotoxicity in a dose-dependent manner, which may correlate with upregulation of γ-aminobutyric acid and subsequent neuronal degeneration after the initial acrylamide exposure.

Gut Bacterial and Lactobacilli Communities of Weaning Piglets in Response to Mannan Oligosaccharide and Sugar Beet Pulp In vitro Fermentation

Microbiota in the gastrointestinal tract （GIT） of piglets during weaning transition can experience a sharp change which could result in growth reduction and diarrhea of weaned piglets. Dietary manipulations can play an important role in attenuating such changes caused by weaning stress. Therefore, ileal and colonic contents of weaned piglets were used as inocula, mannan oligosaccharide （MOS） or sugar beet pulp （SBP） was supplied as single energy sources to investigate effects of MOS or SBP on the shifts of gastro-intestinal microflora and lactobacilli populations. The universal bacteria- and lactobacilli-specific PCR/denaturing gradient gel electrophoresis （DGGE）, cloning and sequencing techniques were used. DGGE profiles of the universal bacteria showed that great changes were found in the position, numbers and intensity of dominant bands after fermentation. The similarity of bacterial community between ileum and colon was increased to 85-97% by MOS or SBP treatment after fermentation from the similarity with 20% before fermentation. MOS treatment significantly increased the bacterial diversity and band number in both ileal and colonic fermentation （P〈0.05）. SBP treatment significantly increased the bacterial diversity and band number in colon （P〈0.05）. It implies that some species were enriched by the addition of MOS or SBP to increase the similarity and diversity of bacterial community in weaned piglets. Five specific bands appearing in MOS or SBP treatment group after fermentation were cloned and sequenced, the changes of species related to Prevotella and Ruminococcus were observed. Two bands related to uncultured bacterium with 98% similarity were detected by MOS or SBP treatment. However, there were no effects on the similarity, diversity index and lactobacilli species revealed by MOS or SBP treatment. These results imply that MOS or SBP could have beneficial effects on the weaning piglets by stablizing microbiota in the GIT microflora.

Sequential invasive-noninvasive mechanical ventilation weaning strategy for patients after tracheostomy

BACKGROUND: Because the continuity and integrity of the trachea are likely damaged to some extent after tracheostomy, the implementation of sequential ventilation has certain difficulties, and sequential invasive-noninvasive ventilation on patients after tracheostomy is less common in practice. The present study aimed to investigate the feasibility of invasive-noninvasive sequential weaning strategy in patients after tracheostomy.METHODS: Fifty patients including 24 patients with withdrawal of mechanical ventilation(conventional group) and 26 patients with sequential invasive-noninvasive weaning by directly plugging of tracheostomy(sequential group) were analyzed retrospectively after appearance of pulmonary infection control(PIC) window. The analysis of arterial blood gases, ventilator-associated pneumonia(VAP) incidence, the total duration of mechanical ventilation, the success rate of weaning and total cost of hospitalization were compared between the two groups.RESULTS: Arterial blood gas analysis showed that the sequential weaning group was better than the conventional weaning group 1 and 24 hours after invasive ventilation. The VAP incidence was lowered, the duration of mechanical ventilation shortened, the success rate of weaning increased, and the total cost of hospitalization decreased.CONCLUSION: Sequential invasive-noninvasive ventilator weaning is feasible in patients after tracheostomy.

Application of fiberoptic bronchscopy in patients with acute exacerbations of chronic obstructive pulmonary disease during sequential weaning of invasive-noninvasive mechanical ventilation

BACKGROUND:Early withdrawal of invasive mechanical ventilation(IMV) followed by noninvasive MV(NIMV) is a new strategy for changing modes of treatment in patients with acute exacerbations of chronic obstructive pulmonary disease(AECOPD) with acute respiratory failure(ARF).Using pulmonary infection control window(PIC window) as the switch point for transferring from invasive to noninvasive MV,the time for early extubation can be more accurately judged,and therapy efficacy can be improved.This study aimed to prospectively investigate the clinical effectiveness of fiberoptic bronchscopy(FOB) in patients with AECOPD during sequential weaning of invasive-noninvasive MV.METHODS:Since July 2006 to January 2011,106 AECOPD patients with ARF were treated with comprehensive medication and IMV after hospitalization.Patients were randomly divided into two groups according to whether fiberoptic bronchoscope is used(group A,n=54) or not(group B,n=52) during sequential weaning from invasive to noninvasive MV.In group A,for sputum suction and bronchoalveolar lavage(BAL),a fiberoptic bronchoscope was put into the airway from the outside of an endotracheal tube,which was accompanied with uninterrupted use of a ventilator.After achieving PIC window,patients of both groups changed to NIMV mode,and weaned from ventilation.The following listed indices were used to compare between the groups after treatment:1) the occurrence time of PIC,the duration of MV,the length of ICU stay,the success rate of weaning from MV for the first time,the rate of reventilatJon and the occurrence rate of ventilator-associated pneumonia(VAP);2) the convenience and safety of FOB manipulation.The results were compared using Student's f test and the Chi-square test.RESULTS:The occurrence time of PIC was(5.01 ±1.49) d,(5.87±1.87) d in groups A and B,respectively(P<0.05);the duration of MV was(6.98±1.84) d,(8.69±2.41) d in groups A and B,respectively(P<0.01);the length of ICU stay was(9.25±1.84) d,(11.10±2.63) d in groups A and B,respectively(P<0.01);the success rate of weaning for the first time was 96.30%,76.92%in groups A and B,respectively(P<0.01);the rate of reventilation was 5.56%,19.23%in groups A and B,respectively(P<0.05);and the occurrence rate of VAP was 3.70%,23.07%in groups A and B,respectively(P<0.01).Moreover,it was easy and safe to manipulate FOB,and no side effect was observed.CONCLUSIONS:The application of FOB in patients with AECOPD during sequential weaning of invasive-noninvasive MV is effective in ICU.It can decrease the duration of MV and the length of ICU stay,increase the success rate from weaning MV for the first time,reduce the rate of reventilation and the occurrence rate of VAP.In addition,such a method is convenient and safe in patients of this kind.

Tannic acid prevents post-weaning diarrhea by improving intestinal barrier integrity and function in weaned piglets

Background:Tannic acid(TA)is potential to reduce diarrhea in weaning pigs,but knowledge about the influence of TA on intestinal barrier integrity and function is still scarce.This experiment was conducted to investigate the effects of dietary TA supplementation on growth performance,diarrhea rate,intestinal barrier integrity and function of weaned pigs.Methods:A total of 108 crossbred(Duroc×Landrace×Yorkshire)piglets,with an initial average body weight of 6.60±0.27 kg,were allotted to 3 groups(6 pigs/pen and 6 replicates/group)in a randomized complete block design according to their gender and body weight.Piglets were fed the basal diet with 0(control,CON),0.2%and 1.0%TA,respectively.The trial lasted for 28 d.Results:Compared with the CON group,dietary 0.2%and 1.0%TA supplementation didn’t affect ADFI,ADG and F:G(P>0.05),but reduced diarrhea rate,diarrhea index and diarrhea score of piglets(P<0.05),reduced diamine oxidase(DAO)activity and D-lactic acid concentration in serum(P<0.01).The higher occludin expression and localization were observed in the duodenum,jejunum and ileum after supplementation with 0.2%or 1.0%TA(P<0.05).Adding 0.2%TA to diet significantly decreased crypt depth,increased villus height/crypt depth ratio in the duodenum(P<0.05),and dietary 1.0%TA tended to decrease crypt depth(P<0.10)and significantly decreased villus height(P<0.05)of the ileum.Moreover,lower malondialdehyde content in the ileum was detected in the pigs fed 1.0%TA(P<0.05).In the duodenum,both 0.2%and 1.0%TA groups had higher occludin(OCLN)mRNA and 0.2%TA group had higher zonula occludens-2(ZO-2)level(P<0.05).Meanwhile,dietary 1.0%TA supplementation tended to up-regulate OCLN mRNA levels in the jejunum(P<0.10)and 0.2%TA supplementation tended to up-regulate zonula occludens-1(ZO-1)mRNA levels in the ileum(P<0.10).Conclusion:In conclusion,dietary supplementation of 0.2%or 1.0%TA could effectively alleviate postweaning diarrhea without altering growth performance in weaned piglets,which might be achieved by improving intestinal barrier integrity and function.

Effects of Microencapsulated Compound Acidifier on Acidity and Development of Gastrointestinal Tract in Weaning Piglets

The effects of different types of compound acidifiers （encapsulated and non-encapsulated） in maize-soybean basic diets on acidity and development of the gastrointestinal tract in weaning piglets were investigated in this study. 64 28-day-old weaned Landrace x Yorkshire hybrid piglets with average weight of （7.00 ±0.10） kg were selected and grouped into four treatments with four pigs （ half boars and half sows） in each repeat of four repeats in each treatment based on single-factor test design principles, and the pre-test period was 3 days but the test period was 35 days. The results showed that compared with acid-free diet group, encapsulated compound acidifier could reduce pH of stomach and intestinal in weaning piglets significantly （P 〈 0.01 ）, while Test group 1 could also increase the relative weight of stomach and intestinal in piglets significantly （P 〈 0.05 ）. Compared with non-encapsulated acidifier, encapsulated compound acidifier could greatly decrease pH in jejunum and ileum of weaning piglets （ P 〈 0.05） or relative weight of stomach in piglets （ P〈0.05）, while Test group 1 could also enhance the relative weight of intestinal in piglets significantly （ P 〈0.01 ）. In addition, encapsulated compound acidifiers significantly increased the ratio between the villus height and crypt depth of jejunum （ P 〈0.01 ）. Accordingly, the microencapsulated compound acidifier in diets of weaning piglets can promote the development of gastrointestinal tracts for piglets by reducing pH of gastrointestinal tracts.

Growth performance and rumen microorganism differ between segregated weaning lambs and grazing lambs

Two feeding patterns of the segregated weaning or grazing in the pasture are carried out worldwide in animal production. To investigate the difference of growth performance and rumen microorganism population related to methane metabolism in the two feeding patterns, three groups of lambs （70 in total） were used： Weaning at 21 days old and being subjected to high-concentration diets （3WK group with 20 lambs）, weaning at 35 days old and being subjected to high-concentration diets （5WK group with 20 lambs）, or grazing at pasture with the nursing mother （Grazing group with 30 lambs）. The growth performance, pH value of rumen content, and the rumen microbes were investigated during weaning period and fattening period with approximately 3 months. Our results showed that lambs in 3WK and 5WK groups demonstrated a better growth performance than the lambs in Grazing group, but no significant difference was observed in the pH value between the three groups （P〉0.05）. The total rumen bacterial population of the Grazing lambs was significantly lower than that of 3WK lambs （P〈0.05） and 5WK lambs （P〈0.05）; however, the population of methanogens was 4.2- and 2.7-fold lower in the 3WK （P〈0.05） and 5WK （P〈0.05） lambs compared with Grazing lambs, respectively; protozoa were also 3.5- and 3.4-fold lower in the 3WK （P〈0.05） and 5WK （P〈0.05） lambs, respectively. The results revealed that segregated weaning lambs may have better growth performance, and reduce methane-producing microbes.

Effects of dietary Selenomethionine supplementation on growth performance,antioxidant status,plasma selenium concentration,and immune function in weaning pigs

Background： This study was designed to evaluate the efficacy of DL-selenomethionine （DL^SeMet） supplementation on growth performance, antioxidant status, plasma selenium （Se） concentration, and immune function of weaning pigs. 216 weaning pigs were randomly allocated to 6 treatments with 6 replicates each according to a complete randomized block design. Each replicate had six pigs. Diet of group one was corn-soybean basal diet without any additional Se supplement. Group 2 was supplemented with 0.3 mg/kg of Se from sodium selenite. Groups 3-6 were supplemented with 0.1, 0.3, 0.5, and 0.7 mg/kg of Se from DL-SeMet, respectively. The trial lasted for 42 days. Results： Pigs supplemented with 0.3 and 0.7 mg/kg DL-SeMet obtained better feed gain ratio （P 〈 0.05）. The best antioxidant ability （serum, liver, and muscle） was shown in 0.1-0.3 mg/kg DL-SeMet groups （P〈 0.05）. The plasma Se concentration increased as the dietary DL-SeMet level elevated. The immunity among groups was not affected. Conclusions： DL-SeMet supplementation in the diet significantly improved the growth performance, antioxidant ability and plasma Se content of weaning pigs. DL-SeMet can replace sodium selenite in the diet of weaning pigs.

A Study of Dairy Heifer Rearing Practices from Birth to Weaning and Their Associated Costs on UK Dairy Farms

There are many inputs into the dairy replacement herd which impact not only on the cost of rearing heifers from birth to first calving, but also on their future longevity and production potential. This study determined the current cost of rearing dairy heifers in the UK through the calculation and analysis of individual costs on a subset of 102 UK dairy farms. Each farm was visited and an extensive heifer rearing questionnaire was completed. Current heifer rearing practices were recorded to provide insight into critical management decisions. A cost analysis workbook was developed to calculate the costs of inputs in the preweaning period for labour, calving, feed, housing, health treatments and vaccinations, waste storage, machinery and equipment, and utilities. The average age at weaning was 62 d. The mean cost of rearing from birth to weaning was ￡195.19 per heifer with a mean daily cost of ￡3.14 (excluding the opportunity cost of the calf). This ranged from ￡1.68 to ￡6.11 among farms, reflecting major differences in management strategies and efficiency. The highest contribution to total costs came from feed (colostrum, milk, starter and forage) at 48.5% with milk feeding making up the greatest proportion of this at 37.3%. The next major expenses were bedding and labour, contributing 12.3% and 11.2% respectively. Unsurprisingly, delaying age at weaning increased total cost by ￡3.53 per day. Total costs were on average 45% higher on organic farms than conventional due to higher feed costs and later weaning. Calving pattern also had a strong association with the total cost being lowest with spring calving, intermediate with autumn calving and highest in multi block and all year round calving herds.

Developmental changes in intercellular junctions and Kv channels in the intestine of piglets during the suckling and post-weaning periods

Background： The intestinal epithelium is an important barrier that depends on a complex mixture of proteins and these proteins comprise different intercellular junctions. The purpose of this study was to investigate the postnatal and developmental changes in morphology, intercellular junctions and voltage-gated potassium（Kv） channels in the intestine of piglets during the suckling and post-weaning periods.Results： Samples of the small intestine were obtained from 1-, 7-, 14-, and 21-d-old suckling piglets and piglets on d 1, 3, 5, and 7 after weaning at 14 d of age. The results showed that the percentage of proliferating cell nuclear antigen（PCNA）-positive cells and alkaline phosphatase（AKP） activity, as well as the abundances of E-cadherin,occludin, and Kv1.5 m RNA and claudin-1, claudin-3, and occludin protein in the jejunum were increased from d 1to d 21 during the suckling period（P 〈 0.05）. Weaning induced decreases in the percentage of PCNA-positive cells,AKP activity and the abundances of E-cadherin, occludin and zonula occludens（ZO）-1 m RNA or protein in the jejunum on d 1, 3 and 5 post-weaning（P 〈 0.05）. There were lower abundances of E-cadherin, occludin and ZO-1m RNA as well as claudin-1, claudin-3 and ZO-1 protein in the jejunum of weanling piglets than in 21-d-old suckling piglets（P 〈 0.05）. The abundances of E-cadherin, occludin, ZO-1 and integrin m RNA were positively related to the percentage of PCNA-positive cells.Conclusion： Weaning at 14 d of age induced damage to the intestinal morphology and barrier. While there was an adaptive restoration on d 7 post-weaning, the measured values did not return to the pre-weaning levels, which reflected the impairment of intercellular junctions and Kv channels.

Effects of Organic Selenium on Growth Properties, Selenium Absorption and Utilization, Antioxidant Activity and Immunity in Weaning Piglets

This experiment was conducted to determine the influences of adding organic selenium (Se) on growth properties, Se absorption and utilization, immunity and antioxidant activity in diets of Duroc weaning piglets. This study was performed on 36 (average weight 7.6 kg) weaning piglets. The weaning piglets were randomly allocated to 1 of 4 homogeneous treatments (A, control treatment, no added Se;B, Sodium selenite, 0.3 mg Se/kg feed;C, yeast Se, 0.3 mg Se/kg;D, DL-methionine Se 0.3 mg Se/kg). Every treatment had 3 replicates, every replicate had 3 piglets. The experiment lasted for 35 d, with the first 7 d for adaptation. Feed intake, residual and contaminated feed were recorded every day. Every piglet weight was weighted respectively at beginning and end of experiment. Daily intake, gain weight and feed conversion rates of every replicate were calculated finally. Se concentrations of serum, blood antioxidant and immunity index were analyzed in the 36th d of experiment. The results showed average daily gain of treatment C was significant higher (P 0.05) and D had higher trend than that of treatment A and B (P = 0.06) respectively. And feed and gain ratio of C and D had trends to lower than them of A and B (P = 0.14). However, all the intake of every week and whole period had no significant differences among treatments (P > 0.05). At same time, except for the Immunoglobulin M of treatment D and C was higher than that of treatment A and B significantly (P < 0.05), all the other Se contents of serum, immunity indexes, blood cell parameters and enzymatic activities had no significant differences among treatments (P > 0.05). But they took on some obvious trends. For example, the Se contents and glutathione peroxidase activities increased successively in order of treatment A, B, C and D;the blood urea nitrogen and total bilirubin of treatment A had higher trend than that of other treatments (P = 0.06). All in all, adding to organic Se in basal diets could improve the animal’s healthy levels, growth properties and Se utilization to some extent. Relatively speaking, the DL-methionine Se had more advantages compared to yeast Se.

Weaning-associated feed deprivation stress causes microbiota disruptions in a novel mucin-containing in vitro model of the piglet colon(MPigut-IVM)

Background:Risk factors for the etiology of post-weaning diarrhea,a major problem in swine industry associated with enormous economic losses,remain to be fully elucidated.In concordance with the ethical concerns raised by animal experiments,we developed a new in vitro model of the weaning piglet colon(MPigut-IVM)including a mucin bead compartment to reproduce the mucus surface from the gut to which gut microbes can adhere.Results:Our results indicated that the MPigut-IVM is able to establish a representative piglet archaeal and bacterial colon microbiota in terms of taxonomic composition and function.The MPigut-IVM was consequently used to investigate the potential effects of feed deprivation,a common consequence of weaning in piglets,on the microbiota.The lack of nutrients in the MPigut-IVM led to an increased abundance of Prevotellaceae and Escherichia-Shigella and a decrease in Bacteroidiaceae and confirms previous in vivo findings.On top of a strong increase in redox potential,the feed deprivation stress induced modifications of microbial metabolite production such as a decrease in acetate and an increase in proportional valerate,isovalerate and isobutyrate production.Conclusions:The MPigut-IVM is able to simulate luminal and mucosal piglet microbiota and represent an innovative tool for comparative studies to investigate the impact of weaning stressors on piglet microbiota.Besides,weaning-associated feed deprivation in piglets provokes disruptions of MPigut-IVM microbiota composition and functionality and could be implicated in the onset of post-weaning dysbiosis in piglets.

Fecal Microbiota Succession of Piglets from Birth to Post-weaning by 454 Pyrosequencing Analysis

The objective of this study was to describe the fecal microbiota succession of piglets from birth to postweaning by pyrosequencing.The dominant bacterial phyla were Bacteroidetes,Firmicutes,Proteobacteria,and Fusobacteria,although the composition of the fecal microbiota changed as the piglets grew.Bacteroides,Parabacteroides,Prevotella,Lactobacillus,unclassified Lachnospiraceae,Ruminococcus,Oscillospira,Phascolarctobacterium,and Desulfovibrio were the core genera in the feces of piglets and existed from birth to post-weaning.Bacteroides was the most abundant at birth; however,the proportion of Bacteroides decreased as the piglets aged,while the proportion of Prevotella increased until it became the most abundant genus at the post-weaning stage.Principal coordinate analysis indicated that the microbial communities of piglet fecal samples from birth to postweaning could be separated into four groups according to the similarity of community composition.These corresponded to time points on day 0 (birth); day 7; days 14,21,and 28 (pre-weaning); and day 35 (post-weaning).This study suggests that the development of the intestinal microbiota in the piglet is a gradual and sequential process.This methodology establishes a basis for broader studies to investigate the microbiota of the piglet intestinal tract.

Toxic effect of acrylamide on the development of hippocampal neurons of weaning rats

Although numerous studies have examined the neurotoxicity of acrylamide in adult animals,the effects on neuronal development in the embryonic and lactational periods are largely unknown.Thus,we examined the toxicity of acrylamide on neuronal development in the hippocampus of fetal rats during pregnancy.Sprague-Dawley rats were mated with male rats at a 1：1 ratio.Rats were administered 0,5,10 or 20 mg/kg acrylamide intragastrically from embryonic days 6–21.The gait scores were examined in pregnant rats in each group to analyze maternal toxicity.Eight weaning rats from each group were also euthanized on postnatal day 21 for follow-up studies.Nissl staining was used to observe histological change in the hippocampus.Immunohistochemistry was conducted to observe the condition of neurites,including dendrites and axons.Western blot assay was used to measure the expression levels of the specific nerve axon membrane protein,growth associated protein 43,and the presynaptic vesicle membrane specific protein,synaptophysin.The gait scores of gravid rats significantly increased,suggesting that acrylamide induced maternal motor dysfunction.The number of neurons,as well as expression of growth associated protein 43 and synaptophysin,was reduced with increasing acrylamide dose in postnatal day 21 weaning rats.These data suggest that acrylamide exerts dose-dependent toxic effects on the growth and development of hippocampal neurons of weaning rats.

Effect of Weaning Ages on Pancreatic and Intestinal Chymotrypsin Activity in Piglet

Twelve litters of new born piglets were divided randomly into groups I , I , M and F , and weaned at 17, 21, 28 and 35 days of age, respectively, to determine the effect of weaning age on pancreatic and intestinal chymotrypsin activity in piglets. The results showed that the relative and specific activity of pancreatic chymotrypsin increased significantly 12h after weaning compared with that of sucking piglets at the same age and then decreased and remained low for 2 - 3 weeks after weaning. Total pancreatic chymotrypsin activity had no change with the increase of pancreas weight during day 18 - 50 regardless of weaning (P > 0.05). Chymotrypsin activity of jejunum had the same change as that of pancreas during sulking stage. Jejunum chymotrypin activity decreased in the first week post-weaning in the piglets weaned before day 28, but had no change in groups weaned at 28 or 35 days. The earlier the weaning age, the longer the restoring time. Chymotrypsin activity in jejunum is more sensitive to the effects of weaning age than in duodenum and ileum.