Effect of adding different levels of synbiotic to milk on performance, digestibility, blood parameters and fecal score on Dalaq sucking lambs

Management of suckling lambs in the first trimester guarantees their health and future production. Animal specific physiological status during this period includes the ability to absorb large molecules, especially immunoglobulins, from the gut and to be prone to intestinal infections and diarrhea. Artificial changes in the lamb intestine flora may improve the intestinal environment. The use of antibiotics in the diet of animals kills beneficial bacteria and does not support the cellular immune system well, and overuse of antibiotics increases bacterial resistance to them. Therefore, replacing antibiotics with other compounds such as prebiotics, probiotics and synbiotics is considered as a suitable solution. These compounds have positive effects such as reducing intestinal infections and diarrhea by increasing the microbial balance of the intestine and increasing the absorption of nutrients including immunoglobulins. Synbiotics is a combination of probiotics and prebiotics that reduce the population of pathogenic microbes in the gastrointestinal tract by increasing their interaction. These compounds can also improve food conversion ratio. Synbiotics can have a positive effect on lamb health and growth rate.

The present study was conducted to investigate the effect of adding different levels of synbiotics to milk on performance, digestibility, blood parameters and fecal score on Dalaq sucking lambs. In this study, 24 suckling lambs with an average weight of 5 ±1.7 kg were selected and then all lambs were examined thoroughly to ensure their health and performance. Lambs were randomly used in four equal experimental groups (6 heads). Treatments include: 1) control treatment (without adding synbiotic to milk), 2) treatment receiving 2.5 g of synbiotic, 3) treatment receiving 5 g of synbiotic and 4) treatment receiving 7.5 g of synbiotic. The total duration of the experiment was 90 days, but feeding and recording of functional factors started from day 20 of the period .The lambs were kept in metabolic cages and the diets used in this experiment were prepared and adjusted based on NRC and were given to the lambs in the morning (8 o'clock) and in the evening (16 o'clock) as an appetite suppressant. Daily feed was provided to the lambs in a completely mixed form. Throughout the experiment, lambs had free access to clean drinking water. Daily feed was provided to the animals in a completely mixed form. In this study, a commercial synbiotic product (GmbH, BIOMIN) of Herzogenburg, Austria including Enterococcus faecium, fructooligosaccharide and seaweed extract through milk substitute was used. Milk was given to lambs twice a day (10% of body weight) by pacifiers. lambs were weighed one day per week to evaluate changes in weight. Dry matter intake was measured and fecal score was recorded daily. Feces samples were collected for digestibility in the final week for 5 days. lambs feces were evaluated daily. Feces scores were determined based on 1-firm and consistent, 2-soft and loose, 3-loose and watery, 4-watery with some blood and 5-watery with blood and mucus. Blood sampling was performed on day 83 so that all lambs were sampled intravenously before the morning meal and with dietary restriction for 12 to 14 hours and the blood was taken in two separate tubes, one containing heparin to obtain plasma and the other. Without heparin, the serum was poured to obtain it. The concentrations of blood Parameter were also determined by spectrophotometer.

The results showed that increasing the level of synbiotics in milk leads to an increase in dry matter intake, daily weight and end-of-period weight (P˂0.05) but the feed conversion ratio was not affected by the use of synbiotics (P> 0.05). The digestibility of crude protein, insoluble fiber in acidic detergent, insoluble fiber in neutral detergent, dry matter, organic matter and ether extract did not show a significant difference between experimental treatments (P> 0.05). Immunoglobulins in the blood of lambs increased with increasing synibiotic level in milk (P˂0.05) so that in 7.5 g of cinebbiotic treatment they had the highest and the control treatment had the lowest concentration of immunoglobulins (P˂0.05). Total protein, albumin, globulin and albumin to globulin ratios were not affected by experimental treatments (P<0.05) but cholesterol, glucose, triglyceride, ammonia nitrogen, high-density lipoprotein, and high-density lipoproteins. Lipoproteins with very low density were affected by experimental treatments (P˂0.05) so that increasing the level of synbiotic caused an increase in triglyceride, lipoproteins with low density and very low lipoproteins (P˂0.05). Further consumption of synbiotics in milk reduced cholesterol, glucose, ammonia nitrogen and high-density lipoproteins (P˂0.05). Feces score decreased significantly with increasing sybibiotic level in milk, so that at the level of 5 g of synbiotic, the lowest consistency score was observed and in the control treatment, the highest feces score was observed (P˂0.05). But numerically, the control treatment had the highest number of days of diarrhea (P>0.05). In general, according to the present results, the use of synbiotics in suckling lambs is recommended to improve the performance and health of lambs.

Overall, the results of this study showed that the use of Synbiotics in milk Increases dry matter intake and daily weight gain in lambs. Also, the uptake of immunoglobulins into the blood of lambs increased with increasing synibiotic levels in milk. Elevated levels of synbiotics cause elevated triglycerides, low-density lipoproteins, and very low-density lipoproteins, but decreased cholesterol, glucose, amniotic nitrogen, and lipids .Improvement of feces score and diarrhea was observed with increasing sybiotic level in milk.The use of synbiotics in suckling lambs is necessary to improve the performance and health of suckling lambs.