Physiological, haematological and electroencephalographic responses to heat stress in Katjang and Boer goats.

The present study aimed to determine the effect of repeated heat stress on serum levels of cortisol (CORT), acute phase proteins (APP) and heat shock protein (HSP) 70, haematological indicators, and electroencephalographic (EEG) response in the native Katjang and exotic Boer goats. Six female Katjang (15.7 kg ± 0.68) and six female Boer (16.8 kg ± 1.16) goats aged 5 to 6 months old were exposed to 38 ± 1℃ for 8 h, and the procedure was repeated at three different weeks (weeks 1, 2 and 3). Measurements of rectal temperatures and EEG activity and collection of blood samples were conducted before heat exposure (0 h), immediately after the heat exposure (8 h), and 8 h after completion of heat exposure (16 h) (recovery period). The current results revealed that the Boer animals had significantly higher rectal temperatures (RT), haemoglobin (Hb) and packed cell volume (PCV) counts than their Kajang counterparts. There were significant breed × stage of heat treatment (SHT) × week of heat treatment (WHT) interactions for neutrophil to lymphocyte ratios (NLR). In general, the Katjang animals had elevated NLR compared to those of Boer. The Boer goats had reduced capacity to express serum HSP70 compared to their Katjang counterparts following the heat challenge at week 3. Boer goats demonstrated higher delta waves than the Katjang group, which suggested the former were more stressed following the heat exposure. Breed had a negligible effect on CORT, APP, WBC counts and backfat thickness. Our findings suggested that the Katjang breed, as measured by RT, HB and PCV count, and EEG activity, could be more tolerant to heat stress than Boer. The Katjang goats showed higher HSP70 expression than their Boer counterparts, suggesting improved thermoregulation in the former.

Heat Shock Protein Response to Stress in Poultry: A Review.

Compared to other animal species, production has dramatically increased in the poultry sector. However, in intensive production systems, poultry are subjected to stress conditions that may compromise their well-being. Much like other living organisms, poultry respond to various stressors by synthesising a group of evolutionarily conserved polypeptides named heat shock proteins (HSPs) to maintain homeostasis. These proteins, as chaperones, play a pivotal role in protecting animals against stress by re-establishing normal protein conformation and, thus, cellular homeostasis. In the last few decades, many advances have been made in ascertaining the HSP response to thermal and non-thermal stressors in poultry. The present review focuses on what is currently known about the HSP response to thermal and non-thermal stressors in poultry and discusses the factors that modulate its induction and regulatory mechanisms. The development of practical strategies to alleviate the detrimental effects of environmental stresses on poultry will benefit from detailed studies that describe the mechanisms of stress resilience and enhance our understanding of the nature of heat shock signalling proteins and gene expression.

Alleviation of Catching and Crating Stress by Dietary Supplementation of Bacillus subtilis in Pekin Ducks.

Catching and crating may elicit stress and fear reactions in poultry because the procedures involve human contact and exposure to a novel environment. This study determined the effects of dietary probiotic supplementation on physiological stress, underlying fear, and growth performance of Pekin ducks subjected to catching and 4 h of crating. The study used a 2 × 2 factorial arrangement; the main factors were diet (basal or basal + probiotic) and crating durations (0 or 4 h). From 1 to 21 days of age (doa), birds were fed a basal or basal + probiotic (CLOSTAT® (Bacillus subtilis) (Kemin Industries, Inc., Des Moines, IA, USA), 1 g/kg) diet. At 21 doa, an equal number of ducklings from each dietary group were caught and crated for 4 h or left undisturbed in the home pens. Birds were examined for serum corticosterone (CORT), heat shock protein (HSP) 70, creatine kinase (CK), triglyceride (TG), glucose (GLU), cholesterol (CHOL), and lactate (LAC) concentrations, heterophil to lymphocyte ratios (HLR), tonic immobility (TI) duration, open-field (OF) test, body weight (BW), and feed conversion ratios (FCR). Diet had no significant (p > 0.05) effect on CORT among the non-crated ducks. However, after catching and crating, birds fed the control diet had significantly (p < 0.05) higher CORT than their probiotic-supplemented counterparts. Catching and crating significantly (p < 0.05) elevated HSP70, HLR, GLU, and CHOL but reduced TG in ducks. Birds fed the probiotic-supplemented diet showed significantly (p < 0.05) lower HSP70, HLR, TG, and CK than those fed the control diet. Probiotic-supplemented ducks showed reduced fear-related behaviours, including TI durations, ambulation latency, and body shaking. Diet had a negligible effect on body weights and FCR of ducks at 21 doa. In brief, catching and crating for 4 h augmented Pekin ducks' physiological stress and fear reactions, and supplementing birds with probiotics was beneficial in ameliorating these detrimental effects.

Impact of Feeding Fermented Palm Kernel Cake and High Dietary Fat on Nutrient Digestibility, Enzyme Activity, Intestinal Morphology and Intestinal Nutrient Transporters mRNA Expression in Broiler Chickens under Hot and Humid Conditions.

The study aimed at determining the ileal nutrient digestibility, digestive enzyme activity, intestinal morphology, and nutrient transporters mRNA expressions in broiler chickens fed with fermented PKC (LPKC) based diets with different levels of fat supplementation under hot and humid conditions. From day 22 to 35, broiler chickens were randomly fed with either (1) 20% LPKC-based diet with 5% palm oil, (2) 20% LPKC based diet with 9.5% palm oil, (3) 20% PKC-based diet with 5% palm oil or (4) 20% PKC-based diet with 9.5% palm oil. Feeding LPKC and PKC diets at the finisher phase have not affected the nutrient's digestibility, but a higher level of oil supplementation does. This was seconded by changes in the digestive enzyme activity, villus height, and mRNA expression of nutrient transporters in the higher level of oil-supplemented diets fed chickens. In conclusion, the inclusion of oil at 9.5% in a 20% LPKC/PKC-based diet is necessary to ensure better nutrient digestibility in chickens via improved digestive function, especially in hot and humid tropical regions.

The Effects of Stocking Density and Distances on Electroencephalographic Changes and Cortisol as Welfare Indicators in Brahman Crossbred Cattle.

The objective of the current study was to investigate the effects of stocking density and distances on electroencephalographic changes and cortisol as welfare indicators in Brahman crossbred cattle. Sixty Brahman crossbred heifers were subjected to road transport from a cattle feedlot farm located in Universiti Putra Malaysia (UPM), Serdang to a commercial ruminant abattoir in Shah Alam, Selangor. Animals were assigned to long (850 km) and short (450 km) distances and high (600 sqm), medium (400 sqm), and low (200 sqm) stocking densities. Results revealed that the intensity of cortisol responses and EEG parameters (such as alpha <0.001, beta < 0.001, delta < 0.001, theta < 0.001, MF < 0.001 and Ptot < 0.001) increased significantly. Long-distance transport also resulted in significantly more intense (<0.001) responses to nociception during slaughter than animals that had been transported over a shorter distance, as indicated by EEG and cortisol.

Effects of Stocking and Transport Conditions on Physicochemical Properties of Meat and Acute-Phase Proteins in Cattle.

This study's objective was to evaluate the effects of distance and stocking density on physicochemical properties and oxidative stability of meat and acute-phase proteins in Brahman crossbred cattle transported by road under hot and humid tropical conditions. Sixty Brahman crossbred heifers were subjected to road transport from a cattle feedlot farm located in Universiti Putra Malaysia (UPM), Serdang, to a commercial ruminant abattoir in Shah Alam, Selangor. Animals were assigned to long and short distances and high, medium, and low stocking densities. The results revealed that the intensity of response significantly increased in meat samples from animals subjected to long-distance transportation and higher stocking density. Alpha-1-acid glycoprotein and serum amyloid-A values increased considerably and were different from the baseline values recorded at preload. In conclusion, the current results revealed that the color, pH, shear force values, water holding capacity (WHC), glycogen level, and malondilaldehyde assay (MDA) concentrations in meat and acute-phase proteins (APP) were affected by both distances and stocking densities, as evidenced by the significant changes recorded from the parameters above.

Supplementation of postbiotic RI11 improves antioxidant enzyme activity, upregulated gut barrier genes, and reduced cytokine, acute phase protein, and heat shock protein 70 gene expression levels in heat-stressed broilers.

The aim of this work was to evaluate the impacts of feeding different levels of postbiotic RI11 on antioxidant enzyme activity, physiological stress indicators, and cytokine and gut barrier gene expression in broilers under heat stress. A total of 252 male broilers Cobb 500 were allocated in cages in environmentally controlled chambers. All the broilers received the same basal diet from 1 to 21 d. On day 22, the broilers were weighed and grouped into 7 treatment groups and exhibited to cyclic high temperature at 36 ± 1°C for 3 h per day until the end of the experiment. From day 22 to 42, broilers were fed with one of the 7 following diets: negative control, basal diet (0.0% RI11) (NC group); positive control, NC diet + 0.02% (w/w) oxytetracycline (OTC group); antioxidant control, NC diet + 0.02% (w/w) ascorbic acid. The other 4 other groups were as follows: NC diet + 0.2% cell-free supernatant (postbiotic RI11) (v/w), NC diet + 0.4% cell-free supernatant (postbiotic RI11) (v/w), NC diet + 0.6% cell-free supernatant (postbiotic RI11) (v/w), and NC diet + 0.8% cell-free supernatant (postbiotic RI11) (v/w). Supplementation of different levels (0.4, 0.6, and 0.8%) of postbiotic RI11 increased plasma glutathione peroxidase, catalase, and glutathione enzyme activity. Postbiotic RI11 groups particularly at levels of 0.4 and 0.6% upregulated the mRNA expression of IL-10 and downregulated the IL-8, tumor necrosis factor alpha, heat shock protein 70, and alpha-1-acid glycoprotein levels compared with the NC and OTC groups. Feeding postbiotic RI11, particularly at the level of 0.6%, upregulated ileum zonula occludens-1 and mucin 2 mRNA expressions. However, no difference was observed in ileum claudin 1, ceruloplasmin, IL-6, IL-2, and interferon expression, but downregulation of occludin expression was observed as compared with the NC group. Supplementation of postbiotic RI11 at different levels quadratically increased plasma glutathione peroxidase, catalase and glutathione, IL-10, mucin 2, and zonula occludens-1 mRNA expression and reduced plasma IL-8, tumor necrosis factor alpha, alpha-1-acid glycoprotein, and heat shock protein 70 mRNA expression. The results suggested that postbiotics produced from Lactiplantibacillus plantarum RI11 especially at the level of 0.6% (v/w) could be used as an alternative to antibiotics and natural sources of antioxidants in poultry feeding.

Effects of heat stress on growth performance, selected physiological and immunological parameters, caecal microflora, and meat quality in two broiler strains.

OBJECTIVE: This study was conducted to investigate the effects of normal and heat stress environments on growth performance and, selected physiological and immunological parameters, caecal microflora and meat quality in Cobb 500 and Ross 308 broilers. METHODS: One-hundred-and-twenty male broiler chicks from each strain (one-day-old) were randomly assigned in groups of 10 to 24 battery cages. Ambient temperature on day (d) 1 was set at 32°C and gradually reduced to 23°C on d 21. From d 22 to 35, equal numbers of birds from each strain were exposed to a temperature of either 23°C throughout (normal) or 34°C for 6 h (heat stress). RESULTS: From d 1 to 21, strain had no effect (p>0.05) on feed intake (FI), body weight gain (BWG), or the feed conversion ratio (FCR). Except for creatine kinase, no strain×temperature interactions were observed for all the parameters measured. Regardless of strain, heat exposure significantly (p<0.05) reduced FI and BWG (d 22 to 35 and 1 to 35), immunoglobulin Y (IgY) and IgM, while increased FCR (d 22 to 35 and 1 to 35) and serum levels of glucose and acute phase proteins (APPs). Regardless of temperature, the Ross 308 birds had significantly (p<0.05) lower IgA and higher finisher and overall BWG compared to Cobb 500. CONCLUSION: The present study suggests that the detrimental effects of heat stress are consistent across commercial broiler strains because there were no significant strain×temperature interactions for growth performance, serum APPs and immunoglobulin responses, meat quality, and ceacal microflora population.

Effects of Feeding Different Postbiotics Produced by Lactobacillus plantarum on Growth Performance, Carcass Yield, Intestinal Morphology, Gut Microbiota Composition, Immune Status, and Growth Gene Expression in Broilers under Heat Stress.

The effects of feeding different postbiotics on growth performance, carcass yield, intestinal morphology, gut microbiota, immune status, and growth hormone receptor (GHR) and insulin-like growth factor 1 (IGF-1) gene expression in broilers under heat stress were assessed in this study. A total of 252 one-day-old male broiler chicks (Cobb 500) were randomly assigned in cages in identical environmentally controlled chambers. During the starter period from 1 to 21 days, all the birds were fed the same basal diet. On day 22, the birds were weighed and randomly divided into six treatment groups and exposed to cyclic high temperature at 36 ± 1 °C for 3 h per day from 11:00 to 14:00 until the end of the experiment. From day 22 to 42 (finisher period), an equal number of birds were subjected to one of the following diets: NC (negative control) basal diet; PC (positive control) basal diet + 0.02% oxytetracycline; or AA (ascorbic acid) basal diet + 0.02% ascorbic acid. The other three groups (RI11, RS5 and UL4) were basal diet + 0.3% different postbiotics (produced from different Lactobacillus plantarum strains, and defined as RI11, RS5 and UL4, respectively). The results demonstrated that birds fed RI11 diets had significantly higher final body weight, total weight gain and average daily gain than the birds that received the NC, PC and AA treatments. The feed conversion ratio was significantly higher in the RI11 group compared with the other groups. Carcass parameters were not affected by the postbiotic-supplemented diet. Postbiotic supplementation improved villi height significantly in the duodenum, jejunum and ileum compared to the NC, PC and AA treatments. The crypt depth of the duodenum and ileum was significantly higher in NC group compared to other treatment groups except RI11 in duodenum, and UL4 in ileum was not different with NC groups. The villus height to crypt depth ratio of duodenum and ileum was significantly higher for the postbiotic treatment groups and AA than the PC and NC treatment groups. The postbiotic RI11 group recorded significantly higher caecum total bacteria and Lactobacillus count and lower Salmonella count compared to the NC and PC treatment groups. The Bifidobacterium population in the NC group was significantly lower compared to the other treatment groups. The postbiotic (RI11, RS5 and UL4) and AA treatment groups showed lower Enterobacteriaceae and E. coli counts and caecal pH than the NC and PC treatment groups. The plasma immunoglobulin M (IgM) level was significantly higher in the birds receiving postbiotic RI11 than those receiving other treatments. The plasma immunoglobulin G (IgG) level was higher in the RI11 treatment group than in the NC, AA and RS5 groups. The plasma immunoglobulin A (IgA) level was not affected by postbiotic supplements. The hepatic GHR mRNA expression level was significantly increased in birds fed postbiotics RI11, RS5 and UL4, AA and PC compared to the NC-fed birds. Postbiotic RI11 led to significantly higher hepatic IGF-1 mRNA expression level compared to the NC, PC, and AA treatments. Mortality was numerically lesser in the postbiotic treatment groups, but not significantly different among all the treatments. In conclusion, among the postbiotics applied in the current study as compared with NC, PC and AA, RI11 could be used as a potential alternative antibiotic growth promoter and anti-stress treatment in the poultry industry.

The Effects of Sea and Road Transport on Physiological and Electroencephalographic Responses in Brahman Crossbred Heifers.

The objective of the current study was to evaluate the effects of sea and road transport on the acute phase proteins (APP), cortisol, metabolic, haematological and electroencephalographic (EEG) responses of Brahman crossbred heifers. Sixty Brahman crossbred heifers were subjected to 14 d of transportation by sea from Darwin Port, Australia, to Pasir Gudang Port, Johor, Malaysia, and 330 km of road transportation. Results revealed that the intensity of response for most blood biochemical parameters increased significantly and were different from the baseline values taken while the animals were in Darwin Port, Australia. Haematological results obtained also revealed a significant increase and were different from the baseline values. Cortisol and APP (bovine alpha 1-acid glycoprotein and serum amyloid-A) values increased significantly and were different from the baseline values. Haematological parameters, APP, cortisol and EEG data (alpha, beta, delta and theta waves, total power and median frequency) decreased significantly following 4 and 7 days post-transport, suggesting a recovery of the animals from the stressfulness of transport. In conclusion, the current results revealed that the concentrations of biochemical and haematological parameters, cortisol, APP and EEG data were affected by both sea and road transport as evidenced by the significant changes recorded from the parameters above.

Effects of method and duration of restraint on stress hormones and meat quality in broiler chickens with different body weights.

OBJECTIVE: The study was designed to investigate the effects of restraint method, restraint duration, and body weight on stress-linked hormones (corticosterone, adrenaline, and noradrenaline), blood biochemical (namely glucose and lactate), and the meat quality in broiler chickens. METHODS: A total of 120 male broiler chickens (Cobb 500) were assigned to a 2×3×2 factorial arrangement in a completely randomized design using two restraint methods (shackle and cone), three durations of restraint (10, 30, and 60 s), and two categories of live body weight (1.8±0.1 kg as lightweight and 2.8±0.1 kg as heavyweight). RESULTS: Irrespective of the duration of restraint and body weight, the coned chickens were found to have lower plasma corticosterone (p<0.01), lactate (p<0.001), lower meat drip loss (p<0.01), cooking loss (p<0.05), and higher blood loss (p<0.05) compared with their shackled counterparts. The duration of restraint had significant effects on the meat initial pH (p<0.05), ultimate pH (p<0.05), and yellowness (p<0.01). The lightweight broilers exhibited higher (p< 0.001) blood loss and lower (p<0.05) cooking loss compared to the heavyweight broilers, regardless of the restraint method used and the duration of restraint. However, the interaction between the restraint method, duration of restraint, and body weight contributed to differences in pre-slaughter stress and meat quality. Therefore, the interaction between the restraint method and the duration of restraint affected the meat shear force, lightness (L*) and redness (a*). CONCLUSION: The duration of restraint and body weight undoubtedly affect stress responses and meat quality of broiler chickens. Regardless of the duration of restraint and body weight, the cone restraint resulted in notably lower stress, lower meat water loss, and higher blood loss compared to shackling. Overall, the findings of this study showed that restraint method, duration of restraint, and body weight may affect the stress response and meat quality parameters in broilers and should be considered independently or interactively in future studies.

Effects of Nano-Composite Adsorbents on the Growth Performance, Serum Biochemistry, and Organ Weights of Broilers Fed with Aflatoxin-Contaminated Feed.

The exploration of feed mycotoxin adsorbents to mitigate the adverse effects of mycotoxins on animals has received increasing attention over the last decade. The present study was conducted to assess the efficacy of nano-composite magnetic graphene oxide with chitosan (MGO-CTS) adsorbents against feed contaminated with ~20 ng/g (ppb) aflatoxin (AF). A total of three hundred 1-day-old chicks were randomly distributed into six dietary treatment groups, as follows: basal diet (broilers fed a diet with neither AF nor MGO-CTS added, T1), basal diet + 0.25% MGO-CTS (T2), basal diet + 0.50% MGO-CTS (T3), AF diet + 0.25% MGO-CTS (T4), AF diet + 0.50% MGO-CTS (T5), and AF diet (T6). The two inclusion levels (0.25 and 0.50%) of MGO-CTS significantly (p < 0.05) improved the growth performances and feed conversion ratios of the AF-treated chicks at 1⁻35 days of age, and the impact was more pronounced for 0.5% MGO-CTS. The AF intake markedly increased the relative weights of the liver and kidney, resulting in significant alterations in the serum biochemical parameters, such as albumins, alkaline phosphatase, and SGPT/alanine (ALT), at 35 days of age. However, the chickens fed 0.5% MGO-CTS with AF diets had apparent recovery or restoration of AF-induced organ lesions and aberrant serum profiles. A significant (p < 0.05) reduction in the total AFs was observed in the gastrointestinal tracts of the chickens fed 0.25% or 0.50% adsorbent in combination with AF feed (T4 and T5), with decreases of 28.9% and 53.5%, respectively, compared with that in the chickens fed an AF-contaminated diet (T6). The results of the study indicated that a higher concentration of MGO-CTS (0.50%) was effective in improving the overall performance of broiler chickens by preventing the adverse effects associated with aflatoxicosis.

The effects of low-protein diets and protease supplementation on broiler chickens in a hot and humid tropical environment.

OBJECTIVE: This experiment was conducted to investigate the effects of dietary crude protein (CP) level and exogenous protease supplementation on growth performance, serum metabolites, carcass traits, small intestinal morphology and endogenous protease activity in broiler chickens reared under a tropical climate. METHODS: A total of 480 day-old male broiler chicks were randomly assigned to eight dietary treatments in a 4×2 factorial arrangement. The main effects were CP level (21.0%, 19.7%, 18.5%, or 17.2% from 1 to 21 days and 19.0%, 17.9%, 16.7%, or 15.6% from 22 to 35 days) and protease enzyme supplementation (0 ppm or 500 ppm). All experimental diets were fortified with synthetic feed-grade lysine, methionine, threonine and tryptophan to provide the minimum amino acid recommended levels for Cobb 500. RESULTS: Reducing dietary CP linearly reduced (p<0.05) growth performance, serum albumin, total protein, and carcass traits and increased (p<0.05) serum triglycerides and abdominal fat. There was no consistent effect of reducing dietary CP on morphological parameters of the intestine and on the pancreatic and intestinal endogenous protease activity (p>0.05). Protease supplementation improved (p<0.05) feed conversion ratio, body weight gain, carcass yield and intestinal absorptive surface area. CONCLUSION: Protease supplementation, as measured by growth performance, intestinal morphology and carcass yield, may alleviate the detrimental effects of low protein diets in broiler chickens.

Bleeding Efficiency, Microbiological Quality and Oxidative Stability of Meat from Goats Subjected to Slaughter without Stunning in Comparison with Different Methods of Pre-Slaughter Electrical Stunning.

The influence of pre-slaughter electrical stunning techniques and slaughter without stunning on bleeding efficiency and shelf life of chevon during a 14 d postmortem aging were assessed. Thirty two Boer crossbred bucks were randomly assigned to four slaughtering techniques viz slaughter without stunning (SWS), low frequency head-only electrical stunning (LFHO; 1 A for 3 s at a frequency of 50 Hz), low frequency head-to-back electrical stunning (LFHB; 1 A for 3 s at a frequency of 50 Hz) and high frequency head-to-back electrical stunning (HFHB; 1 A for 3 s at a frequency of 850 Hz). The SWS, LFHO and HFHB goats had higher (p<0.05) blood loss and lower residual hemoglobin in muscle compared to LFHB. The LFHB meat had higher (p<0.05) TBARS value than other treatments on d 7 and 14 d postmortem. Slaughtering methods had no effect on protein oxidation. Higher bacterial counts were observed in LFHB meat compared to those from SWS, LFHO and HFHB after 3 d postmortem. Results indicate that the low bleed-out in LFHB lowered the lipid oxidative stability and microbiological quality of chevon during aging.

Changes of microbial spoilage, lipid-protein oxidation and physicochemical properties during post mortem refrigerated storage of goat meat.

Examined was the effect of post mortem refrigerated storage on microbial spoilage, lipid-protein oxidation and physicochemical traits of goat meat. Seven Boer bucks were slaughtered, eviscerated and aged for 24 h. The Longissimus lumborum (LL) and Semitendinosus (ST) muscles were excised and subjected to 13 days post mortem refrigerated storage. The pH, lipid and protein oxidation, tenderness, color and drip loss were determined in LL while microbiological analysis was performed on ST. Bacterial counts generally increased with increasing aging time and the limit for fresh meat was reached at day 14 post mortem. Significant differences were observed in malondialdehyde (MDA) content at day 7 of storage. The thiol concentration significantly reduced as aging time increased. The band intensities of myosin heavy chain (MHC) and troponin-T significantly decreased as storage progressed, while actin remained relatively stable. After 14 days of aging, tenderness showed significant improvement while muscle pH and drip loss reduced with increase in storage time. Samples aged for 14 days had higher lightness (P < 0.05) and lower (P < 0.05) yellowness and redness. Post mortem refrigerated storage influenced oxidative and microbial stability and physico-chemical properties of goat meat.

Cytoprotective effect of palm kernel cake phenolics against aflatoxin B1-induced cell damage and its underlying mechanism of action.

BACKGROUND: Palm kernel cake (PKC), a by-product of the palm oil industry is abundantly available in many tropical and subtropical countries. The product is known to contain high levels of phenolic compounds that may impede the deleterious effects of fungal mycotoxins. This study focused on the evaluation of PKC phenolics as a potential cytoprotective agent towards aflatoxin B1 (AFB1)-induced cell damage. METHODS: The phenolic compounds of PKC were obtained by solvent extraction and the product rich in phenolic compounds was labeled as phenolic-enriched fraction (PEF). This fraction was evaluated for its phenolic compounds composition. The antioxidant activity of PEF was determined by using 1,1-diphenyl-2-picryl-hydrazil scavenging activity, ferric reducing antioxidant power, inhibition of ß-carotene bleaching, and thiobarbituric acid reactive substances assays. The cytotoxicity assay and molecular biomarkers analyses were performed to evaluate the cytoprotective effects of PEF towards aflatoxin B1 (AFB1)-induced cell damage. RESULTS: The results showed that PEF contained gallic acid, pyrogallol, vanillic acid, caffeic acid, syringic acid, epicatechin, catechin and ferulic acid. The PEF exhibited free radical scavenging activity, ferric reducing antioxidant power, ß-carotene bleaching inhibition and thiobarbituric acid reactive substances inhibition. The PEF demonstrated cytoprotective effects in AFB1-treated chicken hepatocytes by reducing the cellular lipid peroxidation and enhancing antioxidant enzymes production. The viability of AFB1-treated hepatocytes was improved by PEF through up-regulation of oxidative stress tolerance genes and down-regulation of pro-inflammatory and apoptosis associated genes. CONCLUSIONS: The present findings supported the proposition that the phenolic compounds present in PKC could be a potential cytoprotective agent towards AFB1 cytotoxicity.

Effect of oligosaccharides extract from palm kernel expeller on growth performance, gut microbiota and immune response in broiler chickens.

This study examined the prebiotic effects of oligosaccharides extract from palm kernel expeller (OligoPKE) on growth performance, cecal microbiota and immune response of broiler chickens. A total of ninety 1-day-old broiler chicks (Cobb-500) were randomly allocated to three treatment groups of six pens (replicates) with five birds per pen. Dietary treatments were: (i) basal diet as control, (ii) basal diet plus 0.5% OligoPKE, and (iii) basal diet plus 1% OligoPKE. Birds growth traits (ADG, ADFI and G:F) were measured during the starter (1-21 day), finisher (22-35 day) and the entire experimental periods. Blood and cecal digesta samples were collected from chickens at 21 and 35 days of age (DOA). Microbial quantification of the digesta samples, white blood cells including heterophil, lymphocyte, monocyte, eosinophil, basophil counts and immunoglobulin (IgA and IgM) were also determined. OligoPKE had no effect on ADG and ADFI throughout the study period, but chickens fed OligoPKE supplemented diet had better (P < 0.05) G:F during finisher and overall rearing periods. Supplementing OligoPKE did not significantly alter the birds' microbiota of the cecal digesta. At 21 DOA, blood IgA concentration increased significantly when birds fed 1% OligoPKE in diet recorded compared to the control treatment. Similar observations were also recorded in birds at 35 DOA. Hematological data showed that heterophil and basophil counts of chickens fed OligoPKE supplement were lower than those in control group at 21 DOA. Our findings suggested that OligoPKE improved immune responses in broiler chickens, especially at younger age when the immune system is not still fully developed.

Physico-chemical characteristics of Longissimus lumborum muscle in goats subjected to halal slaughter and anesthesia (halothane) pre-slaughter.

This study assessed the effect of halal slaughter and anesthesia pre-slaughter followed by bleeding on meat quality characteristics of goats. Eleven male Boer cross goats were divided into two groups and subjected to either halal slaughter (HS) or anesthesia with halothane and propofol pre-slaughter (AS). At pre-rigor, HS had significantly lower (P < 0.05) muscle pH and glycogen than AS. However, no significant difference was observed in the pH and glycogen content between the treatments on 1, 3 and 7 days post mortem. The drip loss of HS was significantly lower (P < 0.05) than that of AS at all aging periods. Treatment had no effect on sarcomere length, myofibrillar fragmentation index and shear force values, loss of thiol groups and degradation of major myofibrillar proteins. It can be concluded that HS did not have deleterious effect on meat quality traits of goat when compared to AS.

Environmental temperature and stocking density effects on acute phase proteins, heat shock protein 70, circulating corticosterone and performance in broiler chickens.

An experiment was conducted to determine the effect of different stocking densities on serum corticosterone (CORT), ovotransferrin (OVT), α1-acid glycoprotein (AGP) and ceruloplasmin (CP) concentrations, brain heat shock protein (HSP) 70 expression and performance in broiler chickens exposed to unheated and heated conditions. Day-old chicks were stocked at 0.100 m(2)/bird (low density (LD)) or 0.063 m(2)/bird (high density (HD)), in battery cages and housed in environmentally controlled rooms. From 21 to 35 days of age, birds from each stocking density group were exposed to either 24 or 32 °C. Growth performance was recorded during the heat treatment period, and blood and brain samples were collected to determine CORT, OVT, AGP, CP and HSP 70 levels on day 35. Heat treatment but not stocking density was detrimental to growth performance. There were significant temperature × density interactions for CORT, CP and OVT on day 35. Although HD elevated CORT, CP and OVT when compared to LD, the effects of the former were more obvious under heated condition. Both temperature and density had significant effect on AGP and HSP 70. In conclusion, irrespective of temperature, high stocking density was physiologically stressful to broiler chickens, as indicated by CORT, AGP, CP, OVT and HSP 70, but not detrimental to growth performance and survivability. As it was shown in the present study, AGP, CP and OVT could be useful biomarkers to determine the effect of overcrowding and high temperature on the welfare of broiler chickens.

Effects of two herbal extracts and virginiamycin supplementation on growth performance, intestinal microflora population and Fatty Acid composition in broiler chickens.

The competency of garlic and pennywort to improve broiler chicken growth and influence intestinal microbial communities and fatty acid composition of breast meat were studied. Two hundred forty, "day-old" chicks were randomly allocated to 4 treatment groups consisting of 6 replications of 10 chicks in each pen. The groups were assigned to receive treatment diets as follows: i) basal diet (control), ii) basal diet plus 0.5% garlic powder (GP), iii) basal diet plus 0.5% pennywort powder (PW) and iv) 0.002% virginiamycin (VM). Birds were killed at day 42 and intestinal samples were collected to assess for Lactobacillus and Escherichia coli. The pectoralis profundus from chicken breast samples was obtained from 10 birds from each treatment group on day 42 and frozen at -20°C for further analyses. Fatty acid profile of breast muscles was determined using gas liquid chromatography. Feed intake and weight gain of broilers fed with GP, PW, and VM were significantly higher (p<0.05) compared to control. Feeding chicks GP, PW, and VM significantly reduced Escherichia coli count (p<0.05) while Lactobacillus spp count were significantly higher (p<0.05) in the gut when compared to control group on day 42. Supplemented diet containing pennywort increased the C18:3n-3 fatty acid composition of chickens' breast muscle. Garlic and pennywort may be useful in modulating broiler guts as they control the enteropathogens that help to utilize feed efficiently. This subsequently enhances the growth performances of broiler chickens.