Zulkifli Idrus

Effect of Dietary Lead on Intestinal Nutrient Transporters mRNA Expression in Broiler Chickens

Lead- (Pb-) induced oxidative stress is known to suppress growth performance and feed efficiency in broiler chickens. In an attempt to describe the specific underlying mechanisms of such phenomenon we carried out the current study. Ninety-six one-day-old broiler chicks were randomly assigned to 2 dietary treatment groups of 6 pen replicates, namely, (i) basal diet containing no lead supplement (control) and (ii) basal diet containing 200 mg lead acetate/kg of diet. Following 3 weeks of experimental period, jejunum samples were collected to examine the changes in gene expression of several nutrient transporters, antioxidant enzymes, and heat shock protein 70 (Hsp70) using quantitative real-time PCR. The results showed that addition of lead significantly decreased feed intake, body weight gain, and feed efficiency. Moreover, with the exception of GLUT5, the expression of all sugar, peptide, and amino acid transporters was significantly downregulated in the birds under Pb induced oxidative stress. Exposure to Pb also upregulated the antioxidant enzymes gene expression together with the downregulation of glutathione S-transferase and Hsp70. In conclusion, it appears that Pb-induced oxidative stress adversely suppresses feed efficiency and growth performance in chicken and the possible underlying mechanism for such phenomenon is downregulation of major nutrient transporter genes in small intestine.

Growth performance, duodenal morphology and the caecal microbial population in female broiler chickens fed glycine-fortified low protein diets under heat stress conditions

ABSTRACT 1. This study was undertaken to examine the effect of feeding glycine (Gly)-fortified low protein (LP) diets on the growth performance, duodenal morphology and caecal microbial populations of broiler chickens raised under unheated, cyclic or constant heat stress environmental conditions. 2. From d 1 to 21 (starter phase), an equivalent number of birds were fed either a normal protein (NP) diet or a LP diet fortified with Gly. From d 22 to 42 (grower phase), an equivalent number of birds from each starter diet were distributed to one of the following dietary groups: (i) an NP diet during the starter and grower phases (NPNP), (ii) an NP diet during the starter phase and a LP diet during the grower phase (NPLP), (iii) an LP diet during the starter phase and an NP diet during the grower phase (LPNP) or (iv) LP diets during both phases (LPLP). 3. Commencing from d 22, an equivalent number of birds from each dietary group were exposed to (i) 23 ± 1°C throughout (unheated), (ii) 34 ± 1°C for 7 h each day from 10:00 to 17:00 (cyclic heat) or (iii) 34 ± 1°C throughout (constant heat). 4. Feeding the LP diet during the starter phase resulted in feed intake (FI), weight gain (WG), feed conversion ratios (FCR) and energy efficiency ratios (EER) similar to those for the NP diet. The birds fed the LP diet had a significantly higher protein efficiency ratio (PER) compared with the birds fed the NP diet. 5. During the grower phase, there were significant diet × temperature interactions for F, WG, FCR, PER, EER, villus height, crypt depth and caecal Clostridia. The birds fed the NPLP and LPLP diets had lower FI, WG and EER, higher FCR, shorter villus height and crypt depth and higher caecal Clostridia compared with the birds fed LPNP and NPNP diets under constant heat stress. However, feeding birds the NPLP and LPLP diets resulted in FI, WG, EER, FCR, morphology parameters and caecal Clostridia equivalent to the birds fed LPNP and NPNP diets, as well as improved PER, under unheated and cyclic heat stress conditions. 6. In conclusion, our results indicate that Gly-fortified LP diets can be fed to broilers under normal and acute heat stress environmental conditions without any adverse effects on performance. However, the use of such LP diets can be detrimental to broilers under chronic heat stress conditions.

Carcase characteristics and meat quality assessments in goats subjected to slaughter without stunning and slaughter following different methods of electrical stunning

Abstract The study examined meat quality and carcase haemorrhage in goats subjected to different methods of pre-slaughter electrical stunning or slaughtered without stunning. Thirty-two Boer crossbred bucks were randomly assigned to low-frequency head-only (LFHO; 1 A for 3 s at a frequency of 50 Hz), low-frequency head-to-back (LFHB: 1 A for 3 s at a frequency of 50 Hz) or high-frequency head-to-back (HFHB; 1 A for 3 s at a frequency of 850 Hz) pre-slaughter electrical stunning or slaughter without stunning (SWS). All the 32 animals were bled to drain excess blood from the carcase. The slaughter was performed by a licenced slaughter man by severing carotid artery, jugular vein, trachea and oesophagus. At 12 h post-mortem, LFHO, LFHB and HFHB had lower (p < .05) glycogen and higher lactate and glycolytic potential values than SWS. A faster (p < .05) rate of pH decline was found in LFHO, LFHB and HFHB compared to SWS. No physicochemical parameters except cooking loss differed between treatments. Cooking loss was higher (p < .05) in LFHO, LFHB and HFHB compared to SWS at 7 and 14 d post-mortem. Incidences of carcase haemorrhages in electrically stunned goats were higher than SWS. Nonetheless, HFHB had lower (p < .05) haemorrhages than LFHB and LFHO. Electrical stunning prior slaughter increased carcase haemorrhages and cooking loss but did not affect other meat quality traits in goats.

Response of broiler chickens to dietary inclusion of fermented canola meal under heat stress condition

Abstract Feeding high levels of canola meal to monogastric animal require reducing antinutritional factors such as glucosinolates and fibre. Solid state fermentation is known to reduce antinutritional factors and improve nutritional quality of feedstuffs. In this study, canola meal was treated with Lactobacillus salivarius in solid state fermentation for 30 days and included in diet with 4 levels of 0 (control), 10, 20, and 30%. From 29 to 35 days of age, equal number of birds from each dietary treatment was exposed to either 23 ± 1 °C (unheated) or 36 ± 1 °C (heated). Results showed that irrespective of temperature, weight gain (WG) and feed conversion ratios (FCR) were not affected by inclusion of fermented canola meal (FCM). Diet also did not affect carcass yield, plasma triiodothyronine (T3) and tetraiodothyronine (T4), and body temperature. As expected, heated birds had lower carcass yield and T3 than their unheated counterparts. In conclusion, although dietary inclusion of FCM at levels more than 10% retarded growth performance during 1 to 28 days of age, no detrimental effects on performance was observed when FCM included up to 30% during 29 to 35 days of age under both unheated and heated conditions.

In Ovo and dietary administration of oligosaccharides extracted from palm kernel cake influence general health of pre- and neonatal broiler chicks

Palm kernel cake (PKC) is the main byproduct from the palm oil industry in several tropical countries that contains considerable amounts of oligosaccharide. We earlier demonstrated beneficial prebiotic effects of oligosaccharides extract of PKC (OligoPKC) in starter and finisher broiler birds. This study was envisaged to elucidate the effects of in ovo and/or oral administration of the OligoPKC on prenatal and post-hatched broiler chicks. A total of 140 broiler (Cobb500) eggs were randomly divided into two groups (n = 70 each), and on day 12 of incubation, eggs in one group received in ovo injection of 0.1 mL (containing 20 mg) of OligoPKC, while those in the other group received 0.1 mL of saline (placebo) solution. Of these in ovo placebo or OligoPKC injected eggs, after hatching, six chicks from each group were sampled for day-one analysis, while 48 chicks from each group were randomly allocated to two dietary regimes involving either no feeding or feeding of OligoPKC through basal diet for a 14 days experiment forming the experimental groups as: (i) saline-injected (Control, C), (ii) OligoPKC-injected (PREBovo), (iii) saline-injected, but fed 1% OligoPKC (PREBd), and (iv) OligoPKC-injected and also 1% OligoPKC (PREBovo+d). In ovo injection of prebiotic OligoPKC had no effect on body weight and serum immunoglobulins concentrations of day old chicks, except for IgG, which was increased significantly (P<0.05). Body weight and feed conversion ratio of 14 days old chicks were neither affected by in ovo injection nor feeding of OligoPKC. However, populations of cecal total bacteria and major beneficial bacteria of the chicks were markedly enhanced by feeding of OligoPKC (PREBd and PREBovo+d > C and PREBovo), but lesser influenced by in ovo OligoPKC injection. Irrespective of its prior in ovo exposure, chicks fed OligoPKC diets had lower population of pathogenic bacteria. Overall serum immunoglobulin status of birds was improved by feeding of OligoPKC but in ovo OligoPKC injection had minor effect on that. In most cases, in ovo OligoPKC injection and feeding of OligoPKC reduced the expression of nutrient transporters in the intestine and improved antioxidant capacity of liver and serum. It is concluded that in ovo injection of OligoPKC increased IgG production and antioxidant capacity in serum and liver of prenatal chicks and had limited carrying-over effects on the post-hatched chicks comparing to the supplementary feeding of OligoPKC.

Antiproliferation effects and antioxidant activity of two new Lactobacillus strains

Os micro-organismos mais comumente usados como probioticos sao as bacterias lacticas, especialmente aquelas do genus Lactobacillus. No presente estudo, duas cepas de Lactobacillus, L. pentosus ITA23 e L. acidipiscis ITA44, previamente isoladas da silagem de amora, foram caracterizados por suas atividades antiproliferativas e antioxidantes. Os efeitos antiproliferativos das cepas foram investigados usando-se o ensaio MTT, com linhas de celulas cancerigenas de mama (MDA-MB-231) e do figado (HepG2), e com celulas normais do figado (Chang). As atividades antioxidantes das cepas foram testadas utilizando-se os metodos de FRAP e ABTS. Os resultados demonstraram que as duas cepas de Lactobacillus tinham bons efeitos antiproliferativos contra as duas linhas de celulas cancerigenas, enquanto seus efeitos nas celulas normais eram fracos. Baseando-se nos resultados dos testes antioxidantes, as celulas intactas e os extratos livres de celulas das duas cepas de Lactobacillus demonstraram mais que 135 e menos que 50 µg trolox/mL de atividade antioxidante, respectivamente. Lactobacillus pentosus ITA23 e Lactobacillus acidipiscis ITA44 podem ser considerados como potenciais candidatos probioticos para humanos, devido a sua atividade antioxidante e aos efeitos antiproliferativos contra celulas cancerigenas.

Dose-response relationship of tryptophan with large neutral amino acids, and its impact on physiological responses in the chick model

Tryptophan (Trp) has been associated with the regulation of several behavioral and physiological processes, through stimulation of serotonergic activity. Tryptophan utilization at the metabolic level is influenced by the competitive carrier system it shares with large neutral amino acids (LNAA). This study was carried out using meat-type chicken as a model, to investigate the dose response effects of Trp/LNAA on fear response (tonic immobility; TI) and hormonal responses, including corticosterone (CORT), serotonin (5-HT), triiodothyronine (T3) and thyroxine (T4). A total of 12 cages (48 birds) were assigned to each of the six experimental groups at 29-42 days of age. Experimental diets were formulated to have incremental levels of Trp/LNAA (0.025, 0.030, 0.035, 0.040, 0.045, and 0.050). The results revealed that, Trp/NAA had no significant effect on growth performance and TI of the birds. However, elevation of Trp/LNAA was concurred with a linear reduction in CORT (P < .0001, r2 = 0.819) and linear increases in 5-HT (P < .0001, r2 = 0.945), T3 (P = .0003, r2 = 0.403) and T4 (P < .0001, r2 = 0.937) levels. In conclusion, the results from the current study demonstrated that, although incremental levels of Trp/LNAA did not affect bird growth performance or fearfulness, it increased 5-HT, T3 and T4, and decreased CORT levels in a linear dose-dependent manner. Manipulation of Trp feeding levels could be applied to manage stressful conditions in birds.

Enzymatic hydrolysis drastically reduces fibre content of palm-kernel expeller, but without enhancing performance in broiler chickens

The effectiveness of enzymatic hydrolysis of palm-kernel expeller (PKE) is dependent on various factors that influence the stability and functionality of the enzymes. In the present study, parameters influencing the enzymatic treatment of PKE were optimised employing response surface methodology. In addition, the effectiveness of enzymatic hydrolysed PKE in increasing inclusion rates in broiler diets was evaluated. Results showed that temperature, enzyme concentration and duration of hydrolysis had significant (P < 0.01) effects on the enzymatic hydrolysis of PKE. Using the crude enzyme produced by Aspergillus terreus K1 isolated in our laboratory, maximum reduction of crude fibre (40%) was achieved by fermenting the PKE at 60% initial moisture with 9.0 U/g PKE mannanase at 51°C for 18 h, with the production of 9.9% (w/w) of monosaccharides and oligosaccharides. Results of the growth-performance study indicated that inclusion rate of PKE with or without enzyme treatment in broiler diet is 5% for starter period and 20% for the finisher diet, without any detrimental effect on animal performance. Although the inclusion rate of enzyme-treated PKE can be increased to 30% without affecting average daily gain, feed conversion ratio of the birds will be compromised.

In Vitro Assessment of Bioactivities of Lactobacillus Strains as Potential Probiotics for Humans and Chickens

Twelve previously isolated Lactobacillus strains were investigated for their in vitro bioactivities, including bile salt hydrolase (BSH), cholesterol-reducing and antioxidant activities, cytotoxic effects against cancer cells, enzyme activity, and biogenic amine production. Among them, only 4 strains showed relatively high BSH activity, whereas the rest exhibited low BSH activity. All 12 strains showed cholesterol-reducing and antioxidant activities, especially in their intact cells, which in most of the cases, the isolated strains were stronger in these activities than the tested commercial reference strains. None of the tested strains produced harmful enzymes (β-glucosidase and β-glucuronidase) or biogenic amines. Among the 12 strains, 3 strains were tested for their cytotoxic effects against 3 cancer cell lines, which exhibited strong cytotoxic effects, and they also showed selectivity in killing cancer cells when compared to normal cells. Hence, all 12 Lactobacillus strains could be considered good potential probiotic candidates because of their beneficial functional bioactivities. PRACTICAL APPLICATION The Lactobacillus strains tested in this study could be considered good potential probiotic candidates for food/feed industry because of their beneficial functional bioactivities such as good cholesterol-reducing ability, high antioxidant activity, and good and selective cytotoxic effect against cancer cells.

Response to withdrawal of vitamin and trace mineral premixes from finisher diet in broiler chickens under the hot and humid tropical condition

Abstract This study was conducted to assess the effects of omitting vitamin (VIT) and trace mineral (TRM) premixes from the finisher diet on growth performance, antibody production against Newcastle disease (ND) vaccination, leg bone strength and incidence of foot pad dermatitis (FPD) in male and female broiler chickens. Birds were raised on floor pens in a naturally ventilated house using wood shavings as litter. Commencing from day 21, equal number of male and female birds were subjected to one of four VIT and TRM premixes withdrawal treatments as follows: (i) withdrawal from 21 to 42 days, (ii) withdrawal from 28 to 42 days, (iii) withdrawal from 35 to 42 days, and (iv) no withdrawal (control). In comparison to the control group, feed intake, body weights, feed conversion ratios and antibody responses to Newcastle disease vaccination were not affected by any of the supplement withdrawal treatment. Male birds had lower antibody production and higher bone-breaking strength as compared to their female counterparts. Irrespective of gender, withdrawal of VIT and TRM premixes from 21 to 42, and 28 to 42 days adversely affected bone-breaking strength. In conclusion, VIT and TRM premixes can be removed from the diet of male and female broiler chickens from 21 to 42 days without any adverse effects on growth performance, mortality, antibody response and incidence of foot pad dermatitis. However, bone-breaking strength was adversely affected by the withdrawal of VIT and TRM premixes for more than seven days.