After spending approximately 40 weeks inside the womb, the average newborn weighs 7 1/2 pounds. Most babies weigh between 5 1/2 and 10 pounds. The average length of a newborn is 20 inches (50 centimeters), with a range of 18 to 22 inches. The average head circumference (the distance around the head) is 14 inches (35 centimeters).
Lactobacillus and Bifidobacterium are the most common probiotic bacteria. The Lactobacillus genus has 18 different bacteria strains, while the Bifidobacterium genus consists of eight strains.
The good bacteria most commonly used as probiotics are lactic acid bacteria, such as lactobacillus and bifidobacterium. Not all yogurt contains probiotics, however; some live yogurt contains bacteria that are neither harmful, nor beneficial.ogurt is made by fermenting many types of milk -- including whole, skim, and evaporated milk -- with lactic acid bacteria. These beneficial bacteria are usually from the types called lactobacillus bulgaricus and Streptococcus thermophilus.