S. Jalaludin

Probiotics in poultry: modes of action

This paper reviews recent advances on the use and mode of action of probiotics (direct-fed microbials) in poultry. The addition of probiotics to the diet has been found to improve growth performance and feed conversion in broilers, and egg mass, egg weight and egg size in layers. The mode of action of probiotics in poultry includes (i) maintaining normal intestinal microflora by competitive exclusion and antagonism; (ii) altering metabolism by increasing digestive enzyme activity and decreasing bacterial enzyme activity and ammonia production; (iii) improving feed intake and digestion; and (iv) neutralizing enterotoxins and stimulating the immune system.

EFFECTS OF LACTOBACILLUS CULTURES ON GROWTH PERFORMANCE, ABDOMINAL FAT DEPOSITION, SERUM LIPIDS AND WEIGHT OF ORGANS OF BROILER CHICKENS

1. The effects of a mixture of 12 Lactobacillus strains (LC) on the growth performance, abdominal fat deposition, serum lipids and weight of organs of broiler chickens were studied from 1 to 42 d of age. 2. One hundred and thirty-six 1-d-old male broiler chicks were assigned at random to two dietary treatments: a basal diet (control), and a basal diet with 0·1% LC. 3. The supplementation of LC in broiler diets improved the body weight gain and feed conversion rate from 1 to 42 d of age and was effective in reducing abdominal fat deposition but only after 28 d of age. 4. The LC diets reduced serum total cholesterol, low density lipoprotein (LDL) cholesterol and triglycerides in broilers from 21 to 42 d of age. However, there was no significant difference in serum high density lipoprotein (HDL) cholesterol between control and LC-fed broilers. There was also no significant difference in the weights of organs of control and LC-fed broilers. 5. The results indicated that the mixture of 12 Lactobacillus strains have a hypolipidaemic effect on broilers.

Effects of adherent Lactobacillus cultures on growth, weight of organs and intestinal microflora and volatile fatty acids in broilers

A total of 180 1-day old Arbor Acres chicks was used to investigate the effects of a single L. acidophilus I 26 strain or a mixture of 12 Lactobacillus cultures on the production performance, weight of organs, and intestinal microflora and VFA of broilers. The chicks were assigned randomly into three groups with 60 chicks per treatment. The three dietary treatments were: (i) basal diet (acted as control); (ii) basal diet+1 g kg−1L. acidophilus I 26; and (iii) basal diet+1 g kg−1 mixture of 12 Lactobacillus strains. The results showed that the addition of either a single L. acidophilus I 26 strain or a mixture of 12 Lactobacillus cultures to the basal diet increased significantly (P<0.05) the body weight and feed:gain ratio of broilers for 0–6 weeks. Supplementing the Lactobacillus cultures, singly or in a mixture, in the diet of broilers also decreased significantly (P<0.05) the numbers of coliforms in the cecum 10 and 20 days after feeding, increased significantly (P<0.05) the total VFA in the ileum and cecum, and lowered the cecal pH values. However, the addition of the Lactobacillus cultures in the diets did not increase significantly the lactobacilli population in the ileum and cecum of broilers, except for 30 days after feeding. There were also no significant differences in the populations of total anaerobes, total aerobes, Bifidobacteria and Streptococcus in the ileal and cecal contents of chickens fed with or without Lactobacillus cultures. No significant differences were found in the weight of the liver, spleen, bursa, gizzard, duodenum, jeju-ileum and total small intestine of broilers given the different dietary treatments.

Acid and bile tolerance of Lactobacillus isolated from chicken intestine

Twelve Lactobacillus strains isolated from chicken intestine were used to investigate acid and bile tolerance in vitro. Ten out of the 12 strains were slightly affected by 0.3% bile salts, showing a delay of growth (d) of 0.6-37.2 min compared with growth in control cultures. Two strains were not affected by the bile salts. Of the 12 strains, seven could be arbitrarily classified as resistant (d < 15 min) and five as tolerant (15 min < d < or = 40 min). Lactobacillus strains from the caecum showed better tolerance to acid than those from the ileum. Generally, the survival of the ileal strains was very low at pH 1.0 and 2.0, and moderate at pH 3.0. In contrast, caecal Lactobacillus strains could survive at pH 1.0 for up to 2 h of incubation; growth was moderate at pH 2.0 and good at pH 3.0 and 4.0.

Adhesion of Lactobacillus isolates to intestinal epithelial cells of chicken.

L.Z. JIN, Y.W. HO, M.A. ALI, N. ABDULLAH, K.B. ONG AND S. JALALUDIN. 1996. A total of 46 Lactobacillus isolates obtained from chicken intestine were assessed on their ability to adhere to the chicken ileal epithelial cell (IEC) in vitro. Twelve out of the 46 isolates showed moderate to good ability to adhere to the IEC. Temperature (between 4°C and 42°C) did not affect attachment. Incubation (contact) time of 30 min was found to be insufficient for the attachment of bacteria to the IEC, but contact time beyond 1 h did not increase this ability. The pH values (4–7) of the suspending buffer did not have any significant effect on the attachment of bacteria to the IEC, but at pH 8 it was reduced significantly (P < 0.05).

Culture conditions influencing phytase production of Mitsuokella jalaludinii, a new bacterial species from the rumen of cattle.

Aims: The effects of pH, temperature, phytate, glucose, phosphate and surfactants on the phytase production of Mitsuokella jalaludinii, a new bacterial species from the rumen of cattle, were evaluated. 
Method and Results: By using batch fermentation, it was found that phytase production of M. jalaludinii was induced by sodium phytate. Inclusion of glucose into rice bran–soybean milk (RB‐SM) medium inhibited the phytase production. Supplementation of 0·05–0·5% of phosphate to RB‐SM medium neither inhibited nor stimulated the phytase production. 
The optimum pH and temperature for the phytase production of M. jalaludinii were 7·02 and 39°C, respectively. Surfactants such as Tween‐80 (0·5% and 1·0%) and Triton X‐100 (1·0%) did not affect the phytase production. 
Conclusions, Significance and Impact of the Study: The study has provided important data on the culture conditions affecting phytase production of M. jalaludinii, which will facilitate future research on the optimization of fermentation processes for production of high phytase activity by M. jalaludinii.

Optimization of carbon and nitrogen sources for phytase production by Mitsuokella jalaludinii, a new rumen bacterial species

Aims: The effects of different carbon and nitrogen sources on phytase production by Mitsuokella jalaludinii were evaluated and the optimization of rice bran (RB) and soybean milk (SM) concentrations in the medium for phytase production was also determined.

Effects of energy and protein supplementation on microbial-N synthesis and allantoin excretion in sheep fed guinea grass.

An experiment was conducted to determine the effects of two types of protein, soybean meal (SBM) and fish meal (FM); and two types of energy supplements, corn flour (CF) and paper pulp (PP) on in vivo digestibility of organic matter (OM), rumen fermentation pattern and dilution rate, rumen microbial-N synthesis and flow of organic matter and nitrogenous compounds through the duodenum in four Merino rams with an average weight of 54.44.5 kg. The relationships between duodenal purine flow and urinary allantoin and duodenal protein/energy (MJ rumen VFA per day) ratio were also investigated. The experiment was conducted in a 44 Latin square design with a 22 factorial arrangement of dietary treatments. The animals, fitted with both rumen and duodenal cannulae were housed in individual crates and fed chopped fresh guinea grass ad libitum twice daily, 100 g molasses and one of the four dietary supplements: (i) 170 g FMa268 g PP (FMaPP); (ii) 170 g FMa268 g CF (FMaCF); (iii) 200 g SBMa200 g PP (SBMaPP); and (iv) 200 g SBMa200 g CF (SBMaCF). Each supplement, at varying rates of rumen degradability, was formulated to provide similar amount of N and gross energy. The results showed that rumen pHs were similar, ranging from pH 5.8 to 6.0, for all animals fed the different dietary supplements. Rumen ammonia concentration was significantly (p<0.05) higher in animals fed SBM (170.2‐ 190.7 mg N l ˇ1 ) than in animals fed FM supplement (166.8‐170.2 mg N l ˇ1 ). Rumen VFA

Colonization of Guinea Grass by Anaerobic Rumen Fungi in Swamp Buffalo and Cattle

Abstract No apparent differences in the invasion and colonization of guinea grass by anaerobic rumen fungi could be distinguished between swamp buffalo and cattle. In both animals, zoospores had attached to leaf and stem fragments 15 min after rumen incubation. At 30 min, rhizoids of germinated zoospores were present in many thin-walled cells and many of the rhizoids were observed to produce “appressoria” for penetration of cell walls about 1 h after incubation. By 6 h, sclerenchyma and vascular tissues were extensively colonized and disruption and degradation of tissues occurred in areas with profuse colonization of rhizoids. Most thin-walled cells were degraded after 24 h of incubation and large sporangia were attached to the vascular cylinders. Sporangia were predominantly spherical, ovoid or oval in shape and sporangia which were cylindrical, filiform or fusiform with an elongated pointed tip were of lesser occurrence. At 48 h, many empty uniporous or multiporous sporangia, which probably were remains of sporangia after the liberation of zoospores, were observed. Some spores with thick, warty walls were also observed at 48 h in buffalo. These warty spores resemble resting spores of some aquatic chytrids and may play a part in the dispersal of the rumen fungi from animal to animal.

Fungal colonization of rice straw and palm press fibre in the rumen of cattle and buffalo

Abstract Fungal colonization and development in rice straw and palm press fibre (mesocarp of oil palm fruit after the extraction of oil) were very similar in both cattle and buffalo. In both animal species, attachment to rice straw by rumen fungal zoospores was rapid, within 15 min of rumen incubation. At 6 h of rumen incubation, thin- and thick-walled tissues were colonized by fungal hyphae and by 24 h fungal colonization was extensive. Fungi were predominantly those with spherical and ovoid sporangia. Fusiform sporangia were in fewer numbers. Fungal colonization was also extensive at 48 and 72 h. The colonization and development of the fungi on the palm press fibre, both untreated and treated with ammonium hydroxide and ether, was slow.