CHAPTER 4 History and Physical Examination of the Weanling and Adolescent
In this chapter, the weanling period is defined as that time when the puppy or kitten is walking and capable of spontaneous urination and defecation (about 3 weeks of age) until they are weaned from the dam (about 8 weeks of age). The adolescent period is defined as that period from weaning until full adult height and normal physiology of the major organs is attained. Some may define the adolescent period as ending with puberty, defined as first estrus in females and in males, as acquisition of normal breeding behaviors and semen quality adequate to effect pregnancy. In cats, the end of the adolescent period averages 6 months of age; in dogs, it varies from 6 months of age in toy breeds to 12 to 15 months of age or older in giant breeds (Table 4-1). In most cases, once puppies and kittens attain a size allowing ready collection of blood and urine samples and performance of other diagnostic tests, rule-out lists and diagnostic and treatment plans are the same as for adults.
|Event||Age at occurrence|
|Capable of walking, urinating, and defecating spontaneously||14 to 21 days|
|Hematocrit/RBC number stabilize near that of adult||8 weeks|
|Renal function nears that of adult||8 weeks|
|Hepatic function nears that of adult||4 to 5 months|
RBC, Red blood cell.
Collecting a Comprehensive History
Although clients with a sick puppy or kitten often resent the time taken by a technician or veterinarian to ask historical questions, collection of a relevant history leads the veterinarian’s physical examination and diagnostic testing and may impact plans for therapy. If a significant number of pediatric patients are seen in a practice, it may be beneficial to use the following history questions to create a history template that can be filled out (either as a hard copy or electronically) as puppies and kittens are admitted to the practice.
Duration of Illness
Knowledge of the duration of illness helps the veterinarian differentiate acute from chronic disease and may direct the practitioner toward a specific diagnosis. It also guides interpretation of clinical signs noted on physical examination, for example, a kitten that has been ill for days and is not dehydrated is probably less severely ill than the animal that has acutely become nonresponsive.
Clinical Signs Noted by the Owner
The owner should be asked to specifically list any clinical abnormalities noted, recognizing that some, such as diarrhea, may be difficult to assess if the bitch or queen is doing a good job of cleaning the neonate. Some clinical signs indicate an emergent situation, and any puppy or kitten exhibiting these signs should be seen immediately. Such signs include the following:
Number Affected in the Litter
Infectious diseases and parasite infestations of the neonates and diseases of the bitch are more likely to affect multiple littermates, whereas trauma, congenital disorders, and abnormalities of nursing with subsequent malnutrition are more likely to affect individual puppies or kittens.
Any fluids, supplements, antibiotics, stimulants, human or veterinary drugs of other classes, or herbal therapies and any environmental changes made to allay signs of illness should be recorded. Obtaining this information may require some probing from the technician or veterinarian, since owners may be embarrassed or apprehensive about having used medications intended for humans or other animals on neonates. Knowledge of treatments used alters the interpretation of physical examination findings and may alter treatment recommendations.
History of the Dam
Questions should be asked about the birth of these offspring (e.g., were these puppies or kittens delivered vaginally or by cesarean section [C-section] and did dystocia occur at the time of parturition?); the dam’s current clinical condition and behavior; history of the dam’s mothering skills if she has had previous litters; and health and reproductive history of the dam, including vaccination history.
Because there is minimal antibody transfer across the endotheliochorial placenta of bitches and queens, ingestion of colostrum is necessary for the bulk of passive transfer in puppies and kittens. Antibody titers fall to a nadir at 3 to 4 weeks of life, as maternal antibody concentrations decline before the animal’s own immune system begins to function optimally. If there is concern that a weanling has not received maternal antibodies and needs protection against common diseases until it can respond to vaccination, antibodies can be provided by administration of serum or plasma from any vaccinated adult of the same species, given as subcutaneous boluses. The empirical regimen is administration of 15 ml of serum pooled from several adults, given as 3 boluses administered at 12-hour intervals. Adolescent animals are presumed to have sufficient immune function to permit them to respond to vaccination.
Changes in Body Weight
It is recommended that all neonates be weighed at birth, at 12 and 24 hours of life, and daily thereafter, with good records maintained to document changes in body weight. Any loss of weight after 1 day of age should be a signal to have that neonate seen by a veterinarian; weight loss may precede onset of recognizable signs of disease by as much as 16 hours. Daily weighing should continue until the puppy or kitten is weaned.
Body weight can be used to estimate age of healthy kittens. Most kittens gain weight in a fairly linear fashion so that they weigh about 1 lb at 1 month of age, about 2 lbs at 2 months, and so on until reaching adult weight at about 6 months of age.
Human neonates are scored for various viability measures at birth. The scoring system used was developed by Virginia Apgar, MD, and bears her name. A similar scoring system has been proposed for dogs and cats (see Table 3-2). This system may be most useful as a way of consistently reevaluating an ill puppy or kitten during hospitalization or if they are presented repeatedly. This system provides an objective measure for the medical record for this animal and may be used to guide urgency of diagnostics or alterations in treatment by the veterinary staff.
Body temperature should be measured using a rectal thermometer. It has been demonstrated that rectal thermometry is a more accurate reflection of core body temperature than any other method in adult dogs, and there is no reason to believe that this is not also true in pediatric dogs and cats. Weanlings and adolescents have the same normal body temperature range as adult animals.
Hydration status can be difficult to assess in weanlings. Skin turgor or tenting is not as accurate an indicator of hydration status in pediatric animals as it is in adult animals because neonates have less subcutaneous fat. Oral and ocular mucous membranes may be dry in dehydrated animals. Caution should be used when assessing oral mucous membranes in animals that have recently nursed; milk on the mucous membranes will make them feel slick, artifactually suggesting normal hydration. Normal urine in neonatal animals is very dilute with no discernible color. Stimulation of urination by manipulation of the genitalia is no longer possible once the weanling starts to urinate spontaneously; if the animal is large enough, collection of urine by free catch or cystocentesis may be attempted. Packed cell volume (PCV) cannot be used as a measure of hydration in weanlings because there is a normal decline in PCV with age until it stabilizes at about 8 weeks of age. PCV or change in body weight could be used as a measure of hydration status in adolescent animals, as in adults.
Huddling of the pups on top of each other or near the dam when sleeping is normal; healthy puppies and kittens will not lie apart from littermates or the dam until 5 to 6 weeks of age. When awake, weanling puppies spend a majority of the time exploring and playing. The suckling reflex is strong, but mouthing of other objects and attempts to eat solid food may occur as early as 4 weeks of age.