Journal of Feline Medicine and Surgery

Cats are seasonally polyestrous, meaning they exhibit multiple estrous cycles within a season, followed by a period of non-cyclicity. Cats cycle when the day length is long but can be induced to cycle year-round with 14 h of continuous artificial lighting. The feline estrous cycle includes the following stages: proestrus, estrus, interestrus and, if ovulation occurs, diestrus. Cats are induced ovulators and ovulate in response to multiple natural matings. Successful breeding in a cattery requires knowledge of the female’s reproductive cycle, behavior and management, and often improper management can be the sole cause of infertility.

The aim of this review is to provide readers with an overview of normal anatomy, cyclicity, management and behavior of the queen. It includes a series of questions veterinarians can ask to obtain a baseline knowledge of the management of the specific breeding set-up.

The information in this article is based on the author’s experience, as well as drawing on historical and current literature, and provides the most up-to-date review as possible.

Understanding the normal reproductive anatomy and physiology of the male cat is important for successful breeding. Veterinarians may be called in to troubleshoot when fertility and pregnancy rates decrease in a cattery. By understanding the normal physical parameters, as well as breeding behavior, the veterinarian is better equipped to assess the infertility issue. Also, clients are increasingly requesting breeding soundness examinations prior to mating or purchase. Semen collection is more difficult in the cat than in the dog but can still be accomplished in a clinical setting and provides important information when confronted with breeding males.

The aim of this review is to provide a practical overview of the breeding male. The reader will receive information on time of puberty, normal reproductive anatomy (both external and internal), and breeding management practices to optimize fertility. The most up-to-date semen collection techniques are discussed, as are sedation/anesthesia options. Also, historical literature on the basic anatomy of the male reproductive system is reviewed, such as how the penile spines work and when they appear; this information is specific to the cat.

The information in this article is based on the author’s experience, as well as drawing on historical and current literature, and provides the most up-to-date review as possible.

Cats are common pets worldwide. Successful breeding of cats starts with the selection of suitable breeding animals, and care should be taken to avoid inbreeding. Keeping cats in smaller groups reduces stress and facilitates management.

Breeding cats is challenging in many ways. Group housing is a common scenario, and care should be taken not to have groups that are too large, because of the risk of stress and infectious diseases. Feline pregnancy and parturition both vary in length, which is one reason why it may be challenging to diagnose dystocia. In queens with pyometra, a vaginal discharge may not be evident due to their meticulous cleaning habits.

This review is aimed at clinicians in small animal practice, especially those in contact with cat breeders.

Reproductive emergencies occur in both intentionally and unintentionally bred cats, and more often in young or middle-aged queens. Pyometra tends to be a disease of older queens.

Evidence is poor for many conditions in the breeding queen, and information is extrapolated from the dog or based on case reports and case series.

Despite considerable interest in the field of companion animal reproduction, feline neonatology remains largely unstudied. This contrasts with the need for a more professional veterinary approach to newborn kittens and feline husbandry, across the pet, breeding cattery and rescue shelter settings, to reduce kitten mortality.

Feline neonatology has relevance for veterinarians around the world as cats are continuing to become established as popular companion animals.

Perinatal mortality in cats is remarkably high. Therefore, adequate neonatal evaluation and assistance at birth, careful monitoring of kittens in the vulnerable period until weaning begins, assessment of maternal factors and well-informed management of orphans are crucial in helping to reduce kitten losses.

This review aims to deepen the basic knowledge of the veterinary clinical team regarding the characteristics of feline newborns under normal conditions at birth through to the commencement of weaning. Much of the information is also relevant to breeders and rescue/shelter caregivers.

In compiling the present review, the authors have drawn on specific feline research data, where available, complemented by data extrapolated from scientific publications on newborn dogs, and also their own and their colleagues’ professional clinical experience.

Fading kitten syndrome is a condition where one or more kittens of a litter are born apparently healthy but gradually become inactive, sick and die; typically faders are considered those that die during the first 2 weeks of life. Fading has many potential aetiologies, including a wide variety of infectious, toxic, traumatic, metabolic and genetic diseases. Regardless of the underlying cause, the approach to a sick neonate is similar, and initiating supportive care is the first priority, followed by a detailed physical examination. Where possible, the cause of disease should be determined, and this may inform adjustments to the treatment protocol.

Most perinatal and neonatal diseases present similarly and a specific cause cannot usually be determined from clinical signs alone, which can make diagnosis challenging. When examining a kitten, it is important to remember that there are distinct physiological differences between adults and neonates. In addition, some procedures can be more difficult to perform than in adults, such as blood collection, and some diagnostic tests are harder to interpret, such as radiography. When treating kittens, differences compared with adults again need to be considered.

The aim of this review is to provide guidance to veterinarians who are presented with a fading kitten. As well as reviewing the potential causes of fading kitten syndrome, the diagnostic approach and treatment options are discussed. Algorithms summarising possible pathways to neonatal mortality in kittens, and diagnostic and therapeutic options in fading kittens, are also provided.

Information provided in this review is based on the published feline literature and papers discussing puppies and/or a range of species including cats, as well as the author’s own clinical experience.

Any congenital or developmental abnormality of any part of the male or female reproductive tract is a ‘disorder of sexual development’ (DSD). The tricolored male cat phenotype, cryptorchidism, gonadal hypoplasia and incidental abnormalities such as cystic remnants or embryonic ducts are well-known feline DSDs.

Full characterization of DSDs requires sex chromosome determination and identification of genes related to development of the gonads, internal tubular genitalia and external genitalia. Fortunately, affected cats are seen sporadically and the clinical effects are usually minimal.

The classification nomenclature has changed. In place of intersex, hermaphrodite, pseudohermaphrodite and sex reversal, the newer standard classification, based on sex chromosomes, designates sex chromosome DSD when there is an abnormality in the sex chromosomes, and XX (female) and XY (male) DSDs where there is not. Identification of the gonadal type (testes, ovaries, ovotestes or gonadal dysgenesis) and documentation of the internal and external genital components completes the classification.

The original basis of the DSD classification was a consensus reached in humans. It was quickly accepted in veterinary pathology, courtesy of its logic and ease of application, and it has subsequently begun to appear in peer-reviewed papers and clinical reviews. This article reviewing the various disorders in cats is based on application of the classification and draws on the feline peer-reviewed literature encompassing chromosome analysis and definition of reproductive abnormalities, syndromes and diseases.