Early life antibiotic treatment influences pig intestinal immune programming. Piglets that receive an antibiotic treatment during early life have a less well-developed immune system compared to control piglets, says Dr. Dirkjan Schokker of Wageningen UR (AllAboutFeed, June 4, 2015).

By Jaime Abella Sison, DVM, FPCVFP

Dr. Schokker explained his methodology thus: “We split littermates into three experimental groups: 1) controls; 2) antibiotic treatment at day 4 after birth; and 3) same antibiotic treatment in combination with early life management stressors (including tail docking and nail clipping). By determining the bacterial composition in the gut (microbiota) and the gene activity in the gut wall at days 8, 55, and 176 after birth, it was possible to get more insight into the biology. Both the composition and diversity of gut microbiota was affected and we observed the short- and long-term changes due to these early life treatments.”

Increased activity of immune-related processes in gut tissue. “At day 8 after birth, we observed increased activity of immune-related processes in the gut tissue. Especially genes encoding immune receptors showed highest activity in the control group, followed by the antibiotic/management stressor group, and lastly the antibiotic group.

At day 55, four weeks after weaning, it was not possible to detect treatment specific changes, most probably due to the high variation resulting from the weaning process. However, at day 176, the diversity of the microbiota in the antibiotic treatment group was lower compared to the other two groups. In addition, the activity of the immune system still differed between the treatment groups.”

Early life antibiotic treatment influences gut maturation. “In conclusion, early life antibiotic treatment influences gut maturation, including the programming of the immune system, and may have a life-long impact. Our findings are consistent with the hypothesis that the observed long lasting effects are most probably due to differences in the programming of the gut immune system as induced by the temporary early life changes in the composition and/or diversity of microbiota in the gut. In this context it is worth mentioning that the animal’s genotype also co-determines the pattern of early life microbial colonisation of the gut.”

Enzyme for Wine Could be Antibiotic Alternative for Pigs

Studies by US Department of Agriculture (USDA) scientists have found that a naturally occurring antimicrobial enzyme currently being used in food and beverage applications may also prove useful as an antibiotic alternative for improved feed efficiency and growth in pigs.

William Thomas Oliver, a research physiologist (animals) at USDA’s Agricultural Research Service in Clay Center, Nebraska, and his colleagues began investigating lysozyme, which is used in food and beverage applications such as cheese- and wine-making, in 2010.

Piglets’ Diets Tested

In a recently published trial, they compared the growth rates and weight gains of two groups of
600 piglets placed on one of 3 diet regimens: 1. Corn/soybean meal and specialty protein; 2. The same as 1 with lysozyme added; and 3. Feed containing the antibiotics chlortetracycline and tiamulin hydrogen fumarate rather than the lysozyme.

Piglets’ housing during the trial – The groups were also kept in weaning pens that had either been disinfected or left uncleaned since the last group of animals had occupied them. The latter was done to stimulate chronic, or long-term, immune activity, including the production of cytokines, which divert nutrients away from growth in swine and result in slower weight gain.

12% faster growth in piglets – The results showed that piglets on lysozyme- or antibiotic-treated feeds grew approximately 12% faster than untreated pigs, even in uncleaned pens, suggesting that the treatments successfully ameliorated the effects of indirect immune challenge in the animals.

Pressure on to find antibiotic alternatives for use in pigs – Swine producers are currently under pressure to eliminate sub-therapeutic antibiotic use throughout the production cycle, according to William Oliver, a physiologist at USDA’s Agricultural Research Service in Clay Center, Nebraska. Finding safe and effective alternatives to traditional antibiotics will give swine producers viable options in the event the antibiotics are removed from use, he added.

Antibiotic-resistant bacteria sicken more than 2 million people in the United States each year and kill over 23,000 directly.

This appeared in Agriculture Monthly’s July 2015 issue.