Infusion of short chain fatty acids in the ileum improves the carcass traits,meat quality and lipid metabolism of growing pigs

Short chain fatty acids (SCFA) are the main products of indigestible carbohydrates undergoing bacterial fermentation in the hindgut, which are related to some physiological functions. This study was designed to investigate the effects of SCFA infusion by ileum on the carcass traits, meat quality and lipid metabolism of growing pigs. In a 28-day study, 24 growing barrows fitted with a T-cannula in distal ileum were divided into 4 treatments: 1) Control, 2) antibiotics (AB), 3) AB + 300 mL of SCFA1 solution (ABS1), 4) AB + 300 mL of SCFA2 solution (ABS2). The concentrations of acetate, propionate and butyrate in SCFA1 solution were respectively 61.84, 18.62 and 12.55 mmol/L, and in SCFA2 were respectively 40.08, 15.41 and 9.78 mmol/L. The results showed that the SCFA infusion increased the average daily feed intake and average daily gain of pigs (P < 0.05). Meanwhile, the SCFA treatments increased longissimus dorsi area (P < 0.05) and carcass weight (P = 0.058), decreased the drip loss of longissimus dorsi (P = 0.059), and reduced serum concentrations of triglyceride, total cholesterol and urea nitrogen (P < 0.05). Besides, the SCFA administration inhibited the mRNA expressions of fatty acid synthase (FAS) and acetyl-CoA carboxylase in longissimus dorsi (P < 0.05), the mRNA expression of FAS in the liver (P < 0.05), and the mRNA expression of hormone-sensitive lipase in abdominal fat (P < 0.05). Short chain fatty acid infusion also enhanced the mRNA expression of carnitine palmitoyltransferase-1α in the liver (P < 0.05), the mRNA expressions of peroxisome proliferator activated receptor gamma and lipoprotein lipase in abdominal fat (P < 0.05), and the mRNA expressions of free fatty acid receptor 2, glucose-6-phosphatase and phosphoenolpyruvate carboxykinase 1 in the colon (P < 0.05). These results suggested that SCFA administration in the ileum could improve the carcass traits and meat quality of growing pigs, which was possibly due to the fact that SCFA modulated lipid metabolism.     

A Randomized Study Assessing the Effect of Diet in Cats with Hypertrophic Cardiomyopathy

Background

Diet might influence progression of hypertrophic cardiomyopathy (HCM).

Objective

To investigate whether diet composition could alter clinical, biochemical, or echocardiographic variables in cats with HCM.

Animals

Twenty‐nine cats with HCM (International Small Animal Cardiac Health Council stage 1b) examined at a university teaching hospital.

Methods

Randomized, placebo‐controlled trial. After physical examination, echocardiogram, and blood collection, cats were randomized to 1 of 3 diets, which varied in carbohydrate and fat content and ingredients. Measurements were repeated after 6 months.

Results

There were no significant differences among the 3 groups at baseline. After 6 months, there were no significant changes in the primary endpoints, left ventricular free wall (Group A, P = .760; Group B, P = .475; Group C, P = .066) or interventricular septal thickness in diastole (Group A, P = .528; Group B, P = .221; Group C, P = .097). Group A had significant increases in BUN (P = .008) and cholesterol (P = .021), while Group B had significant increases in BUN (P = .008), cholesterol (P = .007), and triglycerides (P = .005), and significant decreases in NT‐proBNP (P = .013) and hs‐troponin I (P = .043). Group C had significant decreases in body weight (P = .021), left atrial dimension (P = .035), interventricular septal thickness in systole (P = .038), and liver enzymes (P = .034–.038).

Conclusions and Clinical Importance

These data suggest that diet might influence some clinical, biochemical, and echocardiographic variables in cats with HCM.     

Effects of Bacillus subtilis on jejunal integrity,redox status,and microbial composition of intrauterine growth restriction suckling piglets

The present study used intrauterine growth restriction (IUGR) piglets as an animal model to determine the effect of Bacillus subtilis on intestinal integrity, antioxidant capacity, and microbiota in the jejunum of suckling piglets. In total, 8 normal birth weight (NBW) newborn piglets (1.62 ± 0.10 kg) and 16 newborn IUGR piglets (0.90 ± 0.08 kg) were selected and assigned to three groups. Piglets were orally gavaged with 10-mL sterile saline (NBW and IUGR groups), and IUGR piglets were orally gavaged with 10-mL/d bacterial fluid (B. subtilis diluted in sterile saline, gavage in the dose of 2 × 10⁹ colony-forming units per kg of body weight; IBS group; n = 8). IUGR induced jejunal barrier dysfunction and redox status imbalance of piglets, and changed the abundances of bacteria in the jejunum. Treatment with B. subtilis increased (P < 0.05) the ratio of villus height to crypt depth (VH/CD) in the jejunum, decreased (P < 0.05) the plasma diamine oxidase (DAO) activity, and enhanced (P < 0.05) the gene expressions of zonula occludens-1 (ZO-1), occludin, and claudin-1 in the jejunum of IUGR piglets. Treatment with B. subtilis decreased (P < 0.05) the concentration of protein carbonyl (PC) and increased (P < 0.05) the activities of catalase (CAT) and total superoxide dismutase (T-SOD) in the jejunum of IUGR piglets. Treatment with B. subtilis also increased (P < 0.05) gene expressions of superoxide dismutase 1 (SOD1), CAT, and nuclear factor erythroid 2-related factor (Nrf2), as well as the protein expressions of heme oxygenase-1 (HO-1), SOD1, and Nrf2 in the jejunum of IUGR piglets. Treatment with B. subtilis also improved the abundances and the community structure of bacteria in the jejunum of IUGR piglets. These results suggested that IUGR damaged the jejunal barrier function and antioxidant capacity of suckling piglets, and altered the abundances of bacteria in the jejunum. Treatment with B. subtilis improved the intestinal integrity and antioxidant capacity while also improved the abundances and structure of bacteria in the jejunum of suckling piglets.     

Serum Adipokine Concentrations in Dogs with Acute Pancreatitis

Background

Limited information is available about the role of adipokines in the development and progression of acute pancreatitis (AP) in dogs.

Objectives

To determine whether the circulating concentrations of adipokines differed between healthy dogs and dogs with AP, and whether the circulating concentrations differed between AP survivors and AP nonsurvivors.

Animals

Twenty‐eight healthy dogs and 25 client‐owned dogs with AP.

Methods

Prospective observational cohort study of 25 client‐owned dogs with newly diagnosed AP and 28 otherwise healthy dogs with similar body condition scores. The serum concentrations of leptin, adiponectin, resistin, visfatin, interleukin (IL)‐1β, IL‐6, IL‐10, IL‐18, and tumor necrosis factor (TNF)‐α were measured.

Results

The serum concentrations of leptin (P = .0021), resistin (P = .0010), visfatin (P < .0001), IL‐1β (P < .0001), IL‐6 (P = .0002), IL‐10 (P < .0001), and IL‐18 (P < .0001) were significantly higher in dogs with AP than healthy dogs, whereas the adiponectin concentration (P = .0011) was significantly lower. There were significant differences in the serum concentrations of leptin (P = .028) and adiponectin (P = .046) in survivors and nonsurvivors. After the disappearance of clinical signs, the concentrations of resistin (P = .037) and IL‐1β (P = .027) decreased significantly, whereas the serum concentrations of leptin (P > .999), adiponectin (P = .11), visfatin (P = .83), IL‐6 (P = .82), IL‐10 (P = .82), IL‐18 (P = .56), and TNF‐α (P = .94) did not differ significantly.

Conclusion and Clinical Importance

This study showed that dysregulation of adipokines might be involved in the pathogenesis of AP. In addition, leptin and adiponectin are likely to be associated with mortality rate in AP.     

A water-soluble β-glucan improves growth performance by altering gut microbiome and health in weaned pigs

Beta-glucan has been shown to have a beneficial effect on gastrointestinal health. This experiment was conducted to investigate the effects of β-glucan isolated from Agrobacterium sp. ZX09 on growth performance and intestinal health of weaning pigs. A total of 108 weaned pigs (21 d of age; 6.05 ± 0.36 kg) were randomly divided into 3 groups (6 pens/group; 6 pigs/pen), and the groups were each treated with the following diets: 1) basal diet, 2) basal diet supplemented with 20 mg/kg olaquindox, 3) basal diet supplemented with 200 mg/kg β-glucan, for 21 d. Compared with the control group, pigs fed with 200 mg/kg β-glucan had greaterBW, average daily gain and duodenal villus height to crypt depth ratio (P < 0.05). Olaquindox increased the duodenal or jejunal villus height of pigs compared with β-glucan. Compared with the control group, β-glucan tended to increase the occludin mRNA expression in the jejunum (0.05 < P < 0.10). Beta-glucan enriched the beneficial microbiota in the ileum of pigs (P < 0.05). In conclusion, β-glucan may promote growth performance by improving intestinal health and increasing beneficial microbiota of weaned pigs. The study results will provide valuable theoretical guidance for the utilization of β-glucan in weaned pigs.     

In utero heat stress alters the postnatal innate immune response of pigs

The effects of in utero heat stress (IUHS) range from decreased growth performance to altered behavior, but the long-term impact of IUHS on postnatal innate immune function in pigs is unknown. Therefore, the study objective was to determine the effects of early gestation IUHS on the immune, metabolic, and stress response of pigs subjected to an 8 hr lipopolysaccharide (LPS) challenge during postnatal life. Twenty-four pregnant gilts were exposed to thermoneutral (TN; n = 12; 17.5 ± 2.1 °C) or heat stress (HS; n = 12; cyclic 26 to 36 °C) conditions from days 6 to 59 of gestation, and then TN conditions (20.9 ± 2.3 °C) from day 60 of gestation to farrowing. At 12 wk of age, 16 IUHS and 16 in utero thermoneutral (IUTN) pigs were selected, balanced by sex and given an intravenous injection of LPS (2 µg/kg BW mixed with sterile saline [SAL] and injected at 2 µL/kg BW) or SAL (2 µL/kg BW). Body temperature was monitored every 30 min, and blood was obtained at 0, 1, 2, 3, 4, 6, and 8 hr following the LPS challenge. Blood samples were analyzed for glucose, insulin, non-esterified fatty acids (NEFA), cortisol, and cytokine concentrations. In addition, white blood cell counts were determined at 0 and 4 hr. Hour 0 data were used as covariates. Body temperature was increased (P < 0.01) in LPS (40.88 ± 0.08 °C) vs. SAL (39.83 ± 0.08 °C) pigs. Eosinophils tended to be decreased overall (P = 0.09; 43.9%) in IUHS vs. IUTN pigs. Glucose concentrations were reduced overall (P = 0.05; 5.9%) in IUHS vs. IUTN pigs. The NEFA concentrations tended to be greater (P = 0.07; 143.4%) in IUHS-LPS pigs compared with all other treatments, and IUTN-LPS pigs tended to have greater (127.4%) circulating NEFA concentrations compared with IUTN-SAL and IUHS-SAL pigs. Cortisol was increased (P = 0.04) in IUHS-LPS compared with IUTN-LPS pigs at 3 hr (21.5%) and 4 hr (64.3%). At 1 hr, tumor necrosis factor α was increased (P = 0.01; 115.1%) in IUHS-LPS compared with IUTN-LPS pigs. Overall, interleukin-1β (IL-1β) and interleukin-6 (IL-6) were greater (P < 0.04; 281.3% and 297.8%, respectively) in IUHS-LPS pigs compared with all other treatments, and IUTN-LPS pigs had increased IL-1β and IL-6 concentrations compared with IUTN-SAL and IUHS-SAL pigs. In summary, IUHS altered the postnatal cytokine, metabolic, and physiological stress response of pigs during postnatal life, which may have negative implications toward the innate immune response of IUHS pigs to pathogens.     

Rapamycin administration during an acute heat stress challenge in growing pigs

Study objectives were to determine the effects of rapamycin (Rapa) on biomarkers of metabolism and inflammation during acute heat stress (HS) in growing pigs. Crossbred barrows (n = 32; 63.5 ± 7.2 kg body weight [BW]) were blocked by initial BW and randomly assigned to 1 of 4 environmental-therapeutic treatments: 1) thermoneutral (TN) control (n = 8; TNCon), 2) TN and Rapa (n = 8; TNRapa), 3) HS control (n = 8; HSCon), or 4) HS and Rapa (n = 8; HSRapa). Following 6 d of acclimation to individual pens, pigs were enrolled in two experimental periods (P). During P1 (10 d), pigs were fed ad libitum and housed in TN conditions (21.3 ± 0.2°C). During P2 (24 h), HSCon and HSRapa pigs were exposed to constant HS (35.5 ± 0.4°C), while TNCon and TNRapa pigs remained in TN conditions. Rapamycin (0.15 mg/kg BW) was orally administered twice daily (0700 and 1800 hours) during both P1 and P2. HS increased rectal temperature and respiration rate compared to TN treatments (1.3°C and 87 breaths/min, respectively; P < 0.01). Feed intake (FI) markedly decreased in HS relative to TN treatments (64%; P < 0.01). Additionally, pigs exposed to HS lost BW (4 kg; P < 0.01), while TN pigs gained BW (0.7 kg; P < 0.01). Despite marked changes in phenotypic parameters caused by HS, circulating glucose and blood urea nitrogen did not differ among treatments (P > 0.10). However, the insulin:FI increased in HS relative to TN treatments (P = 0.04). Plasma nonesterified fatty acids (NEFA) increased in HS relative to TN treatments; although this difference was driven by increased NEFA in HSCon compared to TN and HSRapa pigs (P < 0.01). Overall, circulating white blood cells, lymphocytes, and monocytes decreased in HS compared to TN pigs (19%, 23%, and 33%, respectively; P ≤ 0.05). However, circulating neutrophils were similar across treatments (P > 0.31). The neutrophil-to-lymphocyte ratio (NLR) was increased in HS relative to TN pigs (P = 0.02); however, a tendency for reduced NLR was observed in HSRapa compared to HSCon pigs (21%; P = 0.06). Plasma C-reactive protein tended to differ across treatments (P = 0.06) and was increased in HSRapa relative to HSCon pigs (46%; P = 0.03). Circulating haptoglobin was similar between groups. In summary, pigs exposed to HS had altered phenotypic, metabolic, and leukocyte responses; however, Rapa administration had limited impact on outcomes measured herein.     

Effects of increased ambient temperature and supplemental altrenogest before pregnancy establishment in gilts

Heat stress (HS) mitigation strategies are critically needed to combat the substantial economic effects on animal agriculture. The manifestations of seasonal infertility include delayed puberty onset, reduced conception rates, decreased litter size, and increased wean to estrus interval. To assess the effects of HS during early gestation and evaluate the benefit of supplemental altrenogest (ALT) as a mitigation strategy, 30 crossbred postpubertal gilts (157 ± 11 kg body weight) were subjected to estrous synchronization via 14 d oral administration of ALT. Artificial insemination during estrus was performed, and gilts were then placed into one of four treatment groups: HS (35 ± 1 °C for 12 h/31.60 ± 1 °C for 12 h) with (HSALT, n = 7) or without (HSCON, n = 7) 15 mg/d ALT supplementation or thermal neutral (TN; 20 ± 1 °C) conditions with (TNALT, n = 8) or without (TNCON, n = 8) 15 mg/d ALT supplementation until 12 d post-estrus (dpe). Administrating ALT occurred at 0600 hours from 3 to 12 dpe, and rectal temperatures (T_R) and respiration rates (RR) were recorded. Blood was collected via jugular venipuncture on 0, 4, 8, and 12 dpe. Gilts were euthanized humanely at 12 dpe followed by the collection of ovarian tissue, and uterine flushing for conceptus collection. In HS compared with TN gilts, RR and T_R were increased (P < 0.01) but unaffected by ALT supplementation. Feed intake was reduced (P < 0.01) by HS but unaltered by the ALT treatment. Corpora lutea (CL) weight was reduced (P < 0.01) in HSCON gilts when compared with TNCON and HSALT gilts despite progesterone concentrations in serum and luteal tissue not being affected by treatment (P ≥ 0.10). CL diameter was reduced (P ≤ 0.05) in HSALT gilts compared with other treatments. Interleukin-1β (IL1B) uterine flush concentration was not affected (P > 0.20) by environment or ALT supplementation, although moderate (P = 0.06) interaction between environment and ALT existed, as IL1B concentration in TNALT was increased (P = 0.03) compared with TNCON gilts. While environment did not affect conceptus development (P = 0.90), ALT supplementation advanced conceptus elongation (P < 0.01). Collectively, these data demonstrate that HS may affect luteal development before pregnancy establishment, and ALT increases conceptus elongation by 12 dpe.     

Acid-insoluble ash is a better indigestible marker than chromic oxide to measure apparent total tract digestibility in pigs

The aim of this study was to determine the apparent total tract digestibility (ATTD) of nutrients in cottonseed meal (CSM) and soybean meal (SBM) in simple carbohydrate and more complex wheat-based diets using 2 indigestible markers and total faecal collection. Twenty-five Large White × Landrace boars (57.8 kg) were randomly allocated to either a pure wheat diet, 40% CSM or SBM in either a sugar-starch- (1:1) or wheat-based diet for 18 d. Acid-insoluble ash (AIA) and chromic oxide (Cr₂O₃) were included in all diets as indigestible markers. Diets were offered (1,800 g/d per pig) in 3 meals/d from d 1 to 11 and 8 meals/d from d 12 to 17. On d 9, the pigs were moved to individual metabolism cages to allow total faecal collection. On d 18, the pigs were fed hourly for 8 h. After the 8th meal, pigs were anaesthetized and digesta sampled from the terminal ileum and rectum before lethal injection. There were no differences between ATTD of nitrogen (N) determined using AIA as a marker and measured by total faecal collection. On the other hand, the ATTD of N of diets containing CSM in sugar-starch- or wheat-based diets and the pure wheat diet determined using Cr₂O₃ as a marker was less (−3.11%, −4.46% and −6.59%; P < 0.001) than that measured by total faecal collection. The ATTD of N determined using AIA as a marker was highly correlated with that measured using total faecal collection (P < 0.001; R² = 0.95). Similarly, the ATTD of N determined using Cr₂O₃ as a marker was correlated with that measured using total faecal collection, although the correlation was not quite as strong as using AIA (P < 0.001; R² = 0.87). Also, the slope of the regression line and the intercept were closer to unity and zero for the relationship when the ATTD of N was determined using AIA compared to Cr₂O₃ as an indigestible marker. The ATTD of organic and dry matter behaved similarly. These data demonstrate that the basal diet and choice of indigestible marker can substantially influence the ATTD and that the use of AIA as an indigestible marker is more suitable than Cr₂O₃ in digestibility studies in pigs.     

Early life thermal stress: impacts on future temperature preference in weaned pigs (3 to 15 kg)

Thermal stress can result in productivity losses, morbidity, and mortality if proper management practices are not employed. A basic understanding of the relationship between animals and the thermal environment is crucial to assess the environment’s impact on livestock performance. Therefore, the study objective was to evaluate whether different early life thermal stressors (ELTS) altered the temperature preference of pigs later in life. Twelve sows and their litters were randomly exposed to 1 of 3 ELTS treatments from 7 to 9 d of age: early life heat stress (ELHS; cycling 32 to 38 °C; n = 4), early life cold stress (ELCS; 25.4±1.1 °C without heating lamp; n = 4), or early life thermoneutral (ELTN; 25.4±1.1 °C with a heating lamp; n = 4) conditions. From 10 to 20 d, (weaning) all piglets were exposed to ELTN conditions. At weaning, pigs were randomly assigned to groups of 4 of the same sex and ELTS treatment. Temperature preference, where pigs freely choose a temperature, was assessed in 21 groups (n = 7 groups per ELTS treatment) using 1 of 3 thermal gradient apparatuses (22 to 40 °C). Testing began at 26 ± 1.3 d of age to give pigs time to acclimate to solid food after weaning and 1 group per ELTS treatment were tested simultaneously in each apparatus. Pigs were given 24 h to acclimate followed by a 24-h testing period. Behavior (active and inactive), posture (upright, sternal, and lateral lying), and location were documented every 20 min using instantaneous scan samples. Preferred feeding temperature was determined by the latency to empty a feeder in each location. Data were analyzed using PROC MIXED in SAS 9.4. A cubic regression model was used to calculate the peak temperature preference of pigs based on the temperature pigs spent most of their time. The preference range was calculated using peak temperature preference ±SE for each ELTS treatment group. Early life thermal stress altered where pigs spent most of their time within the thermal gradient (P = 0.03) with ELTN pigs preferring cooler temperatures (peak preference of 23.8 °C) compared with their ELCS exposed counterparts (peak preference of 26.0 °C; P < 0.01). However, ELHS exposed pigs (peak preference of 25.6 °C) did not differ in their temperature preference compared with ELTN or ELCS exposed counterparts (P > 0.05). In summary, ELCS exposure altered pig temperature preference later in life indicating that ELTS can alter temperature preference in pigs.     

The effects of birth weight and estimated breeding value for protein deposition on nitrogen efficiency in growing pigs

The effects of birth weight (BiW; low BiW [LBW] vs. high BiW [HBW]) and estimated breeding value (EBV) for protein deposition (low EBV [LBV] vs. high EBV [HBV]) on N retention, N efficiency, and concentrations of metabolites in plasma and urine related to N efficiency in growing pigs were studied. At an age of 14 wk, 10 LBW–LBV (BiW: 1.07 ± 0.09 [SD] kg; EBV: −2.52 ± 3.97 g/d, compared with an average crossbred pig with a protein deposition of 165 g/d), 10 LBW–HBV (BiW: 1.02 ± 0.13 kg; EBV: 10.47 ± 4.26 g/d), 10 HBW–LBV (BiW: 1.80 ± 0.13 kg; EBV: −2.15 ± 2.28 g/d), and 10 HBW–HBV (BiW: 1.80 ± 0.15 kg; EBV: 11.18 ± 3.68 g/d) male growing pigs were allotted to the experiment. The pigs were individually housed in metabolism cages and were subjected to an N balance study in two sequential periods of 5 d, after an 11-d dietary adaptation period. Pigs were assigned to a protein adequate (A) or protein restricted (R, 70% of A) regime in a change-over design. Pigs were fed 2.8 times the energy requirements for maintenance. Nontargeted metabolomics analyses were performed in urine and blood plasma samples. The N retention (in g/d) was higher in the HBW than in the LBW pigs (P < 0.001). The N retention (in g/[kg metabolic body weight (BW^0.75) · d]) and N efficiency, however, were not affected by the BiW of the pigs. The N retention (P = 0.04) and N efficiency (P = 0.04) were higher in HBV than in LVB pigs on the A regime but were not affected by EBV in pigs on the R regime. Restricting the dietary protein supply with 30% decreased the N retention (P < 0.001) but increased the N efficiency (P = 0.003). Nontargeted metabolomics showed that a hexose, free amino acids (AA), and lysophosphatidylcholines were the most important metabolites in plasma for the discrimination between HBV and LBV pigs, whereas metabolites of microbial origin contributed to the discrimination between HBV and LBV pigs in urine. This study shows that BiW does not affect N efficiency in the later life of pigs. Nitrogen efficiency and N retention were higher in HBV than in LBV pigs on the A regime but similar in HBV and LBV pigs on the R regime. In precision feeding concepts aiming to further optimize protein and AA efficiency in pigs, the variation in EBV for protein deposition of pigs should be considered as a factor determining N retention, growth performance, and N efficiency.     

Effect of a carbohydrase admixture in growing pigs fed wheat-based diets in thermoneutral and heat stress conditions

The efficacy of exogenous carbohydrases in pig diets has been suggested to depend on enzyme activity and dietary fiber composition, but recent evidence suggests other factors such as ambient temperature might be important as well. Therefore, we investigated the effect of heat stress (HS) on the efficacy of a multienzyme carbohydrase blend in growing pigs. Ninety-six (barrows: gilts; 1:1) growing pigs with initial body weight (BW) of 20.15 ± 0.18 kg were randomly assigned to six treatments, with eight replicates of two pigs per pen in a 3 × 2 factorial arrangement: three levels of carbohydrase (0, 1X, or 2X) at two environmental temperatures (20 °C or cyclical 28 °C nighttime and 35 °C day time). The 1X dose (50 g/tonne) provided 1,250 viscosimetry unit (visco-units) endo-β-1,4-xylanase, 4,600 units α-l-arabinofuranosidase and 860 visco-units endo-1,3(4)-β-glucanase per kilogram of feed. Pigs were fed ad libitum for 28 d and 1 pig per pen was sacrificed on day 28. There was no enzyme × temperature interaction on any response criteria; thus, only main effects are reported. Enzyme treatment quadratically increased (P < 0.05) BW on day 28, average daily gain (ADG) (P < 0.05), and average daily feed intake (ADFI) (P < 0.05) with the 1X level being highest. HS reduced the BW at day 14 (P < 0.01) and day 28 (P < 0.01), ADG (P < 0.01), and ADFI (P<0.001). There was a trend of increased feed efficiency (G:F) (P < 0.1) in the HS pigs. HS increased apparent jejunal digestibility of energy (P < 0.05) and apparent ileal digestibility of calcium (P < 0.01). At day 1, HS reduced serum glucose (P < 0.001) but increased nonesterified fatty acid (P < 0.01). In the jejunum, there was a trend of increased villi height by carbohydrases (P < 0.1), whereas HS reduced villi height (P < 0.05). HS increased the jejunal mRNA abundance of IL1β in the jejunum (P < 0.001). There was a trend for a reduction in ileal MUC2 (P < 0.1) and occludin (P < 0.1) by HS, and a trend for increased PEPT1 (P < 0.1). There was no effect of HS on alpha diversity and beta diversity of the fecal microbiome, but there was an increase in the abundance of pathogenic bacteria in the HS group. In conclusion, HS did not alter the efficacy of carbohydrases. This suggests that carbohydrases and HS modulate pig performance independently.     

51-Chromium Labeled Erythrocyte Half-time Disappearance from Miniature Swine

Half-time disappearance of ⁵¹Cr-laeled erythrocytes was studied in 39 Sinclair miniature swine at 20 to 46 days of age and again at 79 to 109 days of age. Mean erythrocyte half-time disappearance, disregarding age, was 21.29 (±0.77) days for males and 22.04 (±0.81) days for females. The half-time difference between males and females was not statistically significant (P<0.05). At 20 to 46 days of age the mean erythrocyte half-time disappearance was 19.56 (±1.41) days. The same pigs, tested at 79 to 109 days of age, had a mean erythrocyte half-time disappearance of 23.95 (±1.94) days. There was a significant difference (P<0.01) in erythrocyte half-time disappearance from miniature swine as the result of age and also for age within sex. The grand mean erythrocyte half-time disappearance, for all the miniature swine tested, was 21.67 (±0.54) days. The estimate of heritability was 0.61 for dam effect at 20 to 46 days of age and 0.06 at 79 to 109 days of age. Sire estimate of heritability was 0 at both age groups. It was concluded that the large heritability coefficient found only for dam component in young nursing pigs was the result of maternal environment rather than additive genetic variance.     

Cytokine Concentrations in Bronchoalveolar Lavage Fluid from Horses with Neutrophilic Inflammatory Airway Disease

Background

Multiple cytological patterns occur in bronchoalveolar lavage fluid (BALF) of horses with inflammatory airway disease (IAD). Only few data on BALF cytokine profiles are available for horses with IAD, and are limited to mRNA expression.

Hypothesis/Objective

Cytological profiles of IAD are associated with different BALF immunological pathways. To investigate BALF cytokine concentrations in a large number of horses with neutrophilic IAD.

Animals

One hundred and thirty‐eight client‐owned Standardbred racehorses in active training.

Methods

Prospective observational study. BALF samples were obtained from left and right lungs. Interleukin (IL)‐4, interferon (IFN)‐γ, and tumor necrosis factor (TNF)‐α concentrations were determined by ELISA.

Results

Fourteen horses had normal BALF cytological profiles and 56 exhibited evidence of bilateral neutrophilic IAD. Twenty‐four horses showed BALF with, respectively, IAD‐ and CTL consistent cytology and were excluded; as were 44 horses because of evidence of pulmonary hemorrhage. TNF‐α (56 ± 115 pg/mL; P = .034) and IFN‐γ concentrations (104 ± 247 pg/mL; P = .044) were significantly higher for IAD horses, compared with controls (respectively 19 ± 41 and 80 ± 116 pg/mL). Horses with ‘neutrophil’ subtype had significantly higher IFN‐γ concentrations (110 ± 154 pg/mL), than ‘neutrophil/metachromatic’ (56 ± 54 pg/mL; P = .028) and ‘neutrophil/metachromatic/eosinophil’ subtypes (44 ± 23 pg/mL; P = .012).

Conclusions and Clinical Importance

Cytokine concentrations in BALF suggested that neutrophilic IAD is associated with activation of the innate immune system and a possible T‐helper (Th)‐1 polarized response. This study also suggested that immunological pathways vary according to cytological IAD subtypes.     

Dietary nano chromium picolinate can ameliorate some of the impacts of heat stress in cross-bred sheep

Two studies were conducted to evaluate the effect of nano chromium picolinate (nCrPic) during heat stress (HS) in sheep. In the initial study, 36 Merino × Poll cross-bred sheep were individually penned and allocated to 3 dietary treatments (0, 400 and 800 μg/kg nCrPic) for 8 wk. Body composition was determined at the beginning and end of the experiment using dual energy X-ray absorptiometry. The sheep remained in their dietary groups but were then placed in metabolic cages and randomly allocated within the dietary group to differing ambient temperature regimes, i.e., thermo-neutral (TN) (n = 18) and HS (n = 18), for 3 wk. Dietary nCrPic had no effect on growth performance and body composition during the initial study conducted under TN conditions. Heat stress decreased average daily feed intake (ADFI) (P = 0.002) whereas sheep under HS had reduced average daily gain (ADG) and indeed lost weight (P < 0.001). Dietary nCrPic increased both ADFI (P = 0.041) and ADG (P = 0.049) under both TH and HS conditions such that the performance of sheep receiving supplemental nCrPic and exposed to HS was similar to that of control sheep maintained under TN conditions. Heat stress increased rectal temperature (P < 0.001) and respiration rate (P < 0.001), particularly during the hottest parts of the day as indicated by interactions (P < 0.001) between time of day and thermal treatment. Rectal temperature was lower in sheep fed nCrPic (P = 0.050), particularly under peak HS conditions during the afternoon as indicated by the interactions between dietary nCrPic and time of day (P < 0.001) and dietary nCrPic, thermal treatment and time of day (P = 0.010). Similarly, respiration rate was lower in sheep fed nCrPic under peak HS conditions during the afternoon as indicated by the interactions between dietary nCrPic and thermal treatment (P < 0.001) and dietary nCrPic and time of day (P = 0.030). In conclusion, dietary nCrPic can partially ameliorate the negative effects of HS as indicated by the maintenance of ADFI and decreased physiological responses, such as elevations in rectal temperature and respiration rate.     

Induction of Parturition in the Cow using Cloprostenol and Dexamethasone in Combination

Two experiments were designed to test the hypothesis that induction of parturition in the cow would be more predictable with the simultaneous use of a combination of cloprostenol and dexamethasone than with either hormone used alone.

In experiment I all 19 beef cows treated with 500 μg cloprostenol and 25 mg dexamethasone in combination calved within 72 hours whereas dexamethasone (n = 19) or cloprostenol (n = 16) treatments alone each resulted in two induction failures. In those cows successfully induced, the mean interval from treatment to birth was 34.6 ± 1.4 hours for the cloprostenol plus dexamethasone group, 43.3 ± 2.4 hours for the dexamethasone group and 44.9 ± 2.1 hours for the cloprostenol group. Control cows (n = 15) did not calve during the first 72 hours after treatment with saline. The incidence of retained placenta ranged from 19 to 53% in induced groups whereas placentae were not retained by cows in the control group.

In experiment II all 30 beef cows in the cloprostenol plus dexamethasone group calved within the 72 hour limit, with a mean interval of 39.1 ± 1.0 hours. Twenty-six of 31 cows calved within 72 hours with a mean interval of 51.9 ± 3.4 hours after a single injection of cloprostenol and 29 of 33 cows calved within 72 hours with a mean interval of 52.6 ± 3.3 hours after two injections of cloprostenol, 12 hours apart. Five of 34 control cows calved within 72 hours of time of treatment. The incidence of retained placenta was again high in induced cows. Results indicate that the simultaneous administration of cloprostenol and dexamethasone does constitute a safe, reliable and effective method of inducing parturition in the cow.

     

Genetic relationships between efficiency traits and gut microbiota traits in growing pigs being fed with a conventional or a high-fiber diet

In pigs, the gut microbiota composition plays a major role in the process of digestion, but is influenced by many external factors, especially diet. To be used in breeding applications, genotype by diet interactions on microbiota composition have to be quantified, as well as their impact on genetic covariances with feed efficiency (FE) and digestive efficiency (DE) traits. This study aimed at determining the impact of an alternative diet on variance components of microbiota traits (genera and alpha diversity indices) and estimating genetic correlations between microbiota and efficiency traits for pigs fed a conventional (CO) or a high-fiber (HF) diet. Fecal microbes of 812 full-siblings fed a CO diet and 752 pigs fed the HF diet were characterized at 16 weeks of age by sequencing the V3-V4 region of the 16S rRNA gene. A total of 231 genera were identified. Digestibility coefficients of nitrogen, organic matter, and energy were predicted analyzing the same fecal samples with near infrared spectrometry. Daily feed intake, feed conversion ratio, residual feed intake and average daily gain (ADG) were also recorded. The 71 genera present in more than 20% of individuals were retained for genetic analyses. Heritability (h²) of microbiota traits were similar between diets (from null to 0.38 ± 0.12 in the CO diet and to 0.39 ± 0.12 in the HF diet). Only three out of the 24 genera and two alpha diversity indices with significant h² in both diets had genetic correlations across diets significantly different from 0.99 (P < 0.05), indicating limited genetic by diet interactions for these traits. When both diets were analyzed jointly, 59 genera had h² significantly different from zero. Based on the genetic correlations between these genera and ADG, FE, and DE traits, three groups of genera could be identified. A group of 29 genera had abundances favorably correlated with DE and FE traits, 14 genera were unfavorably correlated with DE traits, and the last group of 16 genera had abundances with correlations close to zero with production traits. However, genera abundances favorably correlated with DE and FE traits were unfavorably correlated with ADG, and vice versa. Alpha diversity indices had correlation patterns similar to the first group. In the end, genetic by diet interactions on gut microbiota composition of growing pigs were limited in this study. Based on this study, microbiota-based traits could be used as proxies to improve FE and DE in growing pigs.     

Ascorbic Acid Improves the Developmental Competence of Porcine Oocytes After Parthenogenetic Activation and Somatic Cell Nuclear Transplantation

In this study, a dose-response assessment was performed to understand the relation between supplementation of media with L-ascorbic acid or vitamin C and porcine oocyte maturation and the in vitro development of parthenotes (PA) and handmade cloned (HMC) embryos. Various concentrations (0, 25, 50 and 100 µg/ml) of vitamin C supplemented in in vitro maturation (IVM) and culture (IVC) media were tested. None of these vitamin C additions affected nuclear maturation of oocytes, yet supplementation at 50 µg/ml led to significantly increased intracellular glutathione (GSH) levels and reduced reactive oxygen species (ROS). When cultured in IVM- and/or IVC-supplemented media, the group supplemented with 50 µg/ml of vitamin C showed improved cleavage rates, blastocyst rates and total cell numbers per blastocyst (P<0.05) compared with other groups (control, 25 µg/ml and 100 µg/ml). In contrast, supplementation with 50 µg/ml vitamin C decreased (P<0.05) the apoptosis index as compared with the groups supplemented with 100 µg/ml. In addition, even with a lower blastocyst rate to start with (37.6 vs. 50.3%, P<0.05), supplementation of HMC embryos with vitamin C ameliorated their blastocyst quality to the extent of PA embryos as indicated by their total cell numbers (61.2 vs. 59.1). Taken together, an optimized concentration of vitamin C supplementation in the medium not only improves blastocyst rates and total cell numbers but also reduces apoptotic indices, whereas overdosages compromise various aspects of the development of parthenotes and cloned porcine embryos.     

Formulation of a rational dosage regimen of ceftiofur hydrochloride oily suspension by pharmacokinetic-pharmacodynamic (PK-PD) model for treatment of swine Streptococcus suis infection

BackgroundOur previously prepared ceftiofur (CEF) hydrochloride oily suspension shows potential wide applications for controlling swine Streptococcus suis infections, while the irrational dose has not been formulated.ObjectivesThe rational dose regimens of CEF oily suspension against S. suis were systematically studied using a pharmacokinetic-pharmacodynamic model method.MethodsThe healthy and infected pigs were intramuscularly administered CEF hydrochloride oily suspension at a single dose of 5 mg/kg, and then the plasma and pulmonary epithelial lining fluid (PELF) were collected at different times. The minimum inhibitory concentration (MIC), minimal bactericidal concentration, mutant prevention concentration (MPC), post-antibiotic effect (PAE), and time-killing curves were determined. Subsequently, the area under the curve by the MIC (AUC_0–24h/MIC) values of desfuroylceftiofur (DFC) in the PELF was obtained by integrating in vivo pharmacokinetic data of the infected pigs and ex vivo pharmacodynamic data using the sigmoid E_max (Hill) equation. The dose was calculated based on the AUC_0–24h/MIC values for bacteriostatic action, bactericidal action, and bacterial elimination.ResultsThe peak concentration, the area under the concentration-time curve, and the time to peak for PELF''s DFC were 24.76 ± 0.92 µg/mL, 811.99 ± 54.70 μg·h/mL, and 8.00 h in healthy pigs, and 33.04 ± 0.99 µg/mL, 735.85 ± 26.20 μg·h/mL, and 8.00 h in infected pigs, respectively. The MIC of PELF''s DFC against S. suis strain was 0.25 µg/mL. There was strong concentration-dependent activity as determined by MPC, PAE, and the time-killing curves. The AUC_0–24h/MIC values of PELF''s DFC for bacteriostatic activity, bactericidal activity, and virtual eradication of bacteria were 6.54 h, 9.69 h, and 11.49 h, respectively. Thus, a dosage regimen of 1.94 mg/kg every 72 h could be sufficient to reach bactericidal activity.ConclusionsA rational dosage regimen was recommended, and it could assist in increasing the treatment effectiveness of CEF hydrochloride oily suspension against S. Suis infections.     

Tumor Necrosis Factor‐α and Interleukin‐6 Concentrations in Cerebrospinal Fluid of Dogs After Seizures

Background

Idiopathic and acquired epilepsy are common in dogs. Up to 30% of these dogs are refractory to pharmacological treatment. Accumulating experimental evidence indicates that brain immune response and presence of inflammatory mediators decrease the threshold for individual seizures and contribute to epileptogenesis.

Hypothesis

Dogs with seizures have higher cerebrospinal interleukin‐6 (IL‐6) and tumor necrosis factor‐α (TNF‐α) concentrations compared to dogs with no seizures.

Methods

A prospective double blinded study; cerebrospinal fluid (CSF) and serum IL‐6, TNF‐α and total protein (TP) concentrations were measured by a blinded investigator for the study group and CSF IL‐6 and TNF‐α levels and TP concentrations were measured in the control group (CG).

Animals

Dogs presented with seizures that had enough CSF collected to allow analysis were included in the study group. Twelve apparently healthy, quarantined, stray dogs served as control (CG).

Results

Cerebrospinal fluid TNF‐α and IL‐6 concentrations were significantly higher (P = .011, P = .039) in dogs with seizures (0 ± 70.66, 0.65 ± 10.93 pg/mL) compared to the CG (0 ± 19, 0.73 ± 0.55 pg/mL). When assessing cytokine concentrations of specifically the idiopathic epilepsy (IE) dogs compared to the CG, only TNF‐α concentrations (8.66 ± 62, 0 ± 19 pg/mL) were significantly higher (P = .01). CSF TP concentrations were not significantly higher in the study dogs compared to the CG.

Conclusions and Clinical Importance

Higher TNF‐α and IL‐6 concentration in the CSF of dogs with naturally occurring seizures. The higher supports the hypothesis that inflammatory processes through certain mediators play a role in the pathogenesis of seizures in dogs.