Newborn puppies and kittens can become compromised quickly. Here’s what you need to know when caring for these fragile animals.
High-risk neonatal puppies and kittens are those that become severely dehydrated or systemically ill, or are falling behind in weight gain. A variety of factors can contribute to these circumstances, of which husbandry is the most common. Failure of passive immunity and/or infectious disease can also contribute.
Caring for these high-risk neonates requires knowledge of normal newborn parameters. Healthy puppies and kittens should be gathered in a loose pile within their enclosure (Figure 1), should have good mucous membrane coloring and should be noted to be “twitching” while asleep; they should not be extremely vocal.
Figure 1. Healthy litter of puppies lying in a loose gathering.
A healthy puppy or kitten will twitch noticeably, almost continuously, while sleeping (see video below). This can even startle them awake or cause them to readjust their sleeping position. In my experience, evaluating for this twitching has been the most important factor when monitoring neonates. A significant decrease or lack of twitching could signify that the animal is not doing well and requires professional evaluation.
Several other factors should be monitored as well when caring for high-risk neonates, including environment, hydration, nutrition, excrement, weight and immunity.
In the first week of life, puppies and kittens rely solely on their external environment for warmth; they are unable to maintain their own body temperature. Environmental temperatures ranging from 75°F to 80°F will support maintaining an optimal neonatal rectal temperature of 98°F to 99°F. Only when a puppy or kitten is maintained at an appropriate temperature is it able to digest milk and thus ready to be fed.
High-risk neonates are typically solitary individuals; an entire litter of high-risk neonates is rare. Those at high risk prefer to snuggle against something warm. IV fluid bags warmed in the microwave (make sure the bag is neither too hot nor too cold) and covered with a tube sock can provide a nice substitute for littermates. A sock will be more inviting to the neonate and, because they can be changed and laundered easily, socks also help keep the area clean.
A well-hydrated puppy or kitten will have adequate skin turgor and good pigment color. Light-colored animals should have bright pink mucous membranes (Figure 2). As for adults, it can be challenging to assess mucous membranes in darkly pigmented neonates. However, there should be areas where assessment is possible, such as the belly.
Figure 2. A neonate with poor perfusion (left), evident by the muddy pink skin color around the nose, compared with a healthy littermate (right). Note the much brighter pink mucous membranes around the nose, indicating better perfusion, in the healthy newborn.
Any fluids administered to a neonate, regardless of route, should be warmed. For mildly dehydrated newborns, subcutaneous fluid administration is appropriate. Crystalloid fluids should be administered at a dose of 1 ml/30 g. In cases of severe dehydration, an intravenous or intraosseous catheter is greatly preferred. Jugular intravenous catheters may be the easiest to obtain, and the femur is an excellent bone for intraosseous placement using a hypodermic 22- or 20-gauge needle. Both routes can be used to administer fluids, blood products, diluted dextrose and antibiotics. Severely hypovolemic neonates can receive approximately 60 ml/kg of crystalloid fluid total during one resuscitation event. In cases of dehydration, the rehydration process should be more gradual.1
Dehydration deficits in neonates are calculated in the same way as for adults: Percent dehydration multiplied by body weight in kg will provide the total fluid deficit in liters.1 The neonate’s maintenance fluid is about 60 to 100 ml/lb/day.1 Colloids can be used in urgent circumstances and are dosed the same as in adults.
Any species-specific milk replacer or goat’s milk can be used to feed neonatal puppies and kittens. Neonates need to be fed every two hours until they are gaining weight steadily and becoming more glossy in appearance. They can be bottle fed only if they are vigorous enough to perform the task adequately. Bottle feeding should not be attempted until the neonate’s Apgar score is between 7 and 10 (Table).2 Neonates with Apgar scores between 4 and 7 should be tube fed via a red rubber catheter (size 8-10 Fr for canine neonates and 5 Fr for neonatal kittens.)
Correct tube length is imperative when tube feeding. The tube should be aligned from the mouth and extended down to the last rib. When placing the tube in the stomach, you will feel resistance as the tube passes the lower esophageal sphincter. Place the animal in sternal recumbency and insert the tube toward the back of the throat on the left side, advancing rather swiftly. A puppy or kitten that is alert enough to be fed will also fight you to some degree during tube placement. Holding the mouth closed and the neck extended while milk is instilled will help keep the tube in place.
It is very common for neonates to grunt and vocalize while being fed. Hearing this is a sign that the tube has been placed correctly. An animal that is too lethargic to swallow the tube and provide some resistance is not quite ready for enteral nutrition. While feeding the neonate, be sure to palpate the area below the lower rib on the left side of the body to ensure you are not overfeeding. A good guideline for feeding volume is approximately 4 to 5 ml/100 g. If the puppy or kitten is showing signs of discomfort during feeding, do not proceed with the entire volume but work up to it incrementally. To prevent residual milk from dripping into the pharynx, risking aspiration, kink the tube before removing it.
Because neonates cannot urinate or defecate without assistance, they should be stimulated both before and after feedings. To stimulate urination, rub the ventral caudal abdomen/inguinal area. Urine should be almost clear in a well-hydrated neonate (urine specific gravity < 1.017). A neonate with darker urine will need a more aggressive fluid therapy plan.
Some neonates may urinate and defecate simultaneously, while others need separate stimulation to produce feces. Do not rub directly on the anus repeatedly to stimulate defecation; this can result in ulceration of the anal tissue and make defecation uncomfortable. Instead, wipe a damp, warm cloth or gauze bilaterally on either the ischium or the pelvis (or both). If ulcerations do occur, use vitamin A & D ointment in between stimulation events.
Neonatal feces should resemble varieties of mustard. It can be bright yellow or darker yellow, with or without “seed” material in it. The seeds are fatty excrement. The feces can be very wet in appearance but should not be completely liquid. The meconium is much darker and gelatinous. At-risk neonates that have not had adequate nutrition may pass meconium much later after birth.
A healthy puppy or kitten will gain about 10% of its body weight daily. High-risk neonates should be weighed twice daily using a gram scale. This will allow minor weight losses and gains to be observed more closely to allow for a necessary intervention sooner rather than later.
Neonates that have failed to nurse on their dam or queen within 18 hours of birth will not have had the opportunity to ingest colostrum. In these cases, plasma or serum can be used as a substitute. If administered within the first 18 to 24 hours of life, the plasma or serum can be given orally to the neonatal puppy. Puppies should receive 0.1 ml/g of adult dog serum.1
In kittens, care should be made to ensure the serum blood type matches that of the kitten. Dosing for kittens is 15 ml non-hemolyzed adult serum/100 g of body weight. This serum should be divided into three total injections given every eight hours for the first 24 hours of life.1
Newborn puppies and kittens can become compromised quickly, particularly in the first week of life. Their owners may miss early warning signs of compromise, only noticing that something is amiss when the neonate has entered a high-risk state.
Dr. Simermeyer is an emergency practitioner at Mount Laurel Animal Hospital in Mount Laurel, NJ. Her professional interests include emergency and critical care, and canine reproduction. She has been breeding Cardigan Welsh Corgis for the past 23 years.
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