Additives used in the production of vaccines may include. 1  suspending fluid (e.g. sterile water, saline, or fluids containing protein); 2  preservatives and stabilizers to help the vaccine remain unchanged (e.g. albumin, phenols, and glycine); and. 3  adjuvants or enhancers to help the vaccine to be more effective.
The other element is a standard Yorkie that falls under or over the expected weight and/or size range. Breed standards have changed. The AKC used to list a minimum weight of 4 pounds (1.81 kg). Now, there is only a maximum weight of 7 pounds (3.17 kg) for a full grown, adult Yorkie. Even with this change on paper, most Yorkshire Terriers fit into the 3 to 7 lb. (1.36 kg to 3.17 kg) range. A dog smaller than this, fully grown, would be considered too small and may have size related health issues.
With teacup yorkies this yorkie growth chart is not very reliable until the puppy is over 12 weeks of age. For the first 12 weeks we look at the chart, but factor in the genetics of the parents and the physical size of the puppy to arrive at an estimated adult weight.