Feeding behaviour in the cat—recent advances

Robenacoxib versus meloxicam following ovariohysterectomy in cats: A randomised, prospective clinical trial involving owner-based assessment of pain

BACKGROUND

Injectable non-steroidal anti-inflammatory drugs (NSAIDs) are commonly prescribed to queens undergoing ovariohysterectomy (OVH), but the requirement for postoperative administration is unclear and practices vary. Existing studies assessing efficacy rely on pain scoring by experienced clinicians. However, following OVH, most cats are discharged within hours of recovery.

METHODS

Cats undergoing OVH were randomly assigned to two treatment groups: MEL and ROB. Cats in the MEL group (n = 76) received meloxicam (0.2 mg/kg) and those in the ROB group (n = 65) received robenacoxib (2 mg/kg). Owners were contacted by a blinded assessor 3 days postoperatively and asked to identify physical or behavioural changes and to assign pain scores using a numerical rating scale.

RESULTS

More cats in the ROB group displayed abnormal behaviours than cats in the MEL group (p = 0.03). Most owners assigned a pain score of 0 (72%) (n = 101), but pain scores were significantly higher in the ROB group than in the MEL group (p = 0.005).

LIMITATION

Methods of owner assessment of pain in cats have not been validated.

CONCLUSIONS

Both meloxicam and robenacoxib are effective in controlling postoperative pain. Meloxicam may have improved efficacy in certain patient populations. Applying a blanket approach to prescribing NSAIDs to cats undergoing OVH postoperatively may not be necessary. This has safety, environmental and cost implications.

Comparison of Locomotor and Feeding Rhythms between Indoor and Outdoor Cats Living in Captivity

The plastic nature of cat behaviour allows this “friendly symbiont” of humans to adapt to various housing conditions. Beyond daylight, one could wonder if other environmental factors affect its patterns. Yet, how its activity and feeding rhythms are impacted by its environment is rarely studied in standardised conditions between populations. We compared the behaviour of cats living in a 29 m2 indoor room and cats living in a 1145 m2 outdoor enclosure, tracking them simultaneously in summer for 21 days, with advanced technologies. Both populations received daylight but weather fluctuations only occurred outdoors. Bimodality was detected in the activity and feeding rhythms of both groups, while twilight triggered crepuscular peaks. Daily, the outdoor population covered more distance (4.29 ± 0.27 km; p < 0.001) and consumed more food (67.44 ± 2.65 g; p < 0.05) than the indoor population (2.33 ± 0.17 km, 57.75 ± 2.85 g, respectively), but displayed less rhythmic behaviours, assumedly because of rhythm disruptors met only in outdoor conditions. Finally, outdoor housing seemed to promote the exploratory behaviour of the cats at night, while indoor housing increased both meal frequency (p = 0.063) and the impact of human interactions on the feeding rhythms of the cats.

Sensory analysis of pet foods

Pet food palatability depends first and foremost on the pet and is related to the pet food sensory properties such as aroma, texture and flavor. Sensory analysis of pet foods may be conducted by humans via descriptive or hedonic analysis, pets via acceptance or preference tests, and through a number of instrumental analysis methods. Sensory analysis of pet foods provides additional information on reasons behind palatable and unpalatable foods as pets lack linguistic capabilities. Furthermore, sensory analysis may be combined with other types of information such as personality and environment factors to increase understanding of acceptable pet foods. Most pet food flavor research is proprietary and, thus, there are a limited number of publications available. Funding opportunities for pet food studies would increase research and publications and this would help raise public awareness of pet food related issues. This mini-review addresses current pet food sensory analysis literature and discusses future challenges and possibilities.

A model to quantify the anticipatory response in cats

The aim of this paper was to develop a protocol to study the anticipatory response in cats as a measure of welfare. Seven experimental cats were trained in a classical conditioning paradigm to associate a sound with food arrival, while sound and food were presented without contingency in four control cats. Increasing the interval between sound and food up to 60 s allowed a detailed description of cats’ anticipatory response. Compared to control animals, experimental cats showed significantly shorter latencies to orient towards (average 2.96 s) and approach the source of the sound (12.98 s) as well as longer durations of exploring and standing by the source of the sound (namely 69.97 and 52.32%, respectively of the interval sound-food). Experimental cats also exhibited behaviours that may derive from predation patterns, eg short pauses and predatory crouch while approaching the source of the sound (namely in 28.93 and 29.64% of trials), rapid head movements while watching it (55.36% of trials) and pouncing on the food (9.29% of trials). This protocol should be further studied to assess its effectiveness in highlighting differences according to the welfare of individual cats.

The evolutionary basis for the feeding behavior of domestic dogs (Canis familiaris) and cats (Felis catus)

The dentition, sense of taste and meal patterning of domestic dogs and cats can be interpreted in terms of their descent from members of the order Carnivora. The dog is typical of its genus, Canis, in its relatively unspecialized dentition, and a taste system that is rather insensitive to salt. The preference of many dogs for large infrequent meals reflects the competitive feeding behavior of its pack-hunting ancestor, the wolf Canis lupus. However, its long history of domestication, possibly 100,000 years, has resulted in great intraspecific diversity of conformation and behavior, including feeding. Morphologically and physiologically domestic cats are highly specialized carnivores, as indicated by their dentition, nutritional requirements, and sense of taste, which is insensitive to both salt and sugars. Their preference for several small meals each day reflects a daily pattern of multiple kills of small prey items in their ancestor, the solitary territorial predator Felis silvestris. Although in the wild much of their food selection behavior must focus on what to hunt, rather than what to eat, cats do modify their food preferences based on experience. For example, the "monotony effect" reduces the perceived palatability of foods that have recently formed a large proportion of the diet, in favor of foods with contrasting sensory characteristics, thereby tending to compensate for any incipient nutritional deficiencies. Food preferences in kittens during weaning are strongly influenced by those of their mother, but can change considerably during at least the first year of life.

Behavioural responses of farm mink towards familiar and novel food

The study aimed to (i) describe the response of farmed mink towards familiar and novel food, and (ii) assess the suitability of using novel food in order to measure fear responses in mink. A total of 48 farm mink from two behaviourally selected genetic lines were caged individually with one standardised daily feeding. The experimental feedings were carried out in a balanced order on 2 successive days. Behaviour of the mink was video recorded for 10min after food provision. In general, the mink were reluctant to approach and eat the novel food compared to familiar food, which indicates a neophobic feeding strategy, i.e. increased latency to come close to (P<0.01) and eat (P<0.001) the novel food, and a higher frequency (P<0.001) and a longer duration (P<0.001) of sniffing. Provision of unknown food items may be used to evaluate fear responses in mink since mink respond reluctantly towards novel food. However, high inter-individual variation in the present study obliterated a previously shown difference between confident and fearful mink, suggesting that this method for measuring fear responses in mink is appropriate only on a large animal material.

Aging does not influence feeding behavior in cats

The aim of this investigation was to see whether aging influences feeding behavior in cats. Two studies were carried out. In the first study, a standard canned cat food was fed to six young adult and six senior cats for 10 d on an ad libitum basis. Feeding behavior was monitored during the final 5 d. In the second study, diets enriched with beef tallow, olive oil or sunflower oil were fed at an equivalent energy intake for 21 d. Feeding behavior was monitored during the final 5 d. The results of both studies indicated no significant differences between the young and old cats in the number of meals consumed, the amount consumed at each meal or the duration of each meal when fed either ad libitum or at equivalent energy intakes. Daily feeding patterns were similar for each of the 5 d for each cat, with cats tending to consume regular small meals throughout the day and night. The only significant differences noted were among the fat-enriched diets. The diet enriched with beef tallow had fewer refusals compared to the diets enriched with olive oil and sunflower oil, indicating a possible palatability differential. It was concluded that cats of all ages are habitual feeders with similar daily feeding patterns, which may be altered only with a change in diet. Given that no differences were seen between the young and senior cats, it cannot be assumed that feeding patterns are responsible for the previously observed age-related decreases in apparent digestibility.

Differences in food preferences between individuals and populations of domestic cats Felis silvestris catus

The food preferences of 64 cats, of which 28 were domestic pets and 36 were free-ranging animals on three farms, were tested using five food types; a sixth type was also tested on the farm cats. Information was also gathered on the background diet of the house cats (individually) and of each farm cat colony. Consistent differences were found between the predefined groups of cats in their preferences for three foods, Hard Dry (HD), Canned Meat (CM) and Raw Beef (RB), the greatest differences being between house cats and farm cats as a whole. The three colonies of farm cats showed distinct differences in preference, for RB and/or CM, and for the sixth food, Soft Dry (SD). Differences between farms could be explained by a reduced preference for items similar to major components of the background diet of each colony, i.e. selection in favour of foods that were temporally rare. Differences between house and farm cats, and within the house cats, could not be explained in this way; the house cats were neophobic towards RB, and the farm cats ate little of the HD food, possibly because they found it difficult to ingest.

Vitamin B-6 deficiency and level of dietary protein affect hepatic tyrosine aminotransferase activity in cats

Total activity [pyridoxal 5'-phosphate (PLP) added in the assay] of hepatic tyrosine aminotransferase (TAT) measured in cats at 0300, 0900, 1500 and 2100h was 10.3 +/-1.1, 14.0 +/- 0.7, 9.8 +/- 1.3 and 11.0 +/- 0.7 nkat/g liver, indicating little diurnal variation. Activity after 18 h of food deprivation was 10.0 +/- 0.3 nkat/g liver, also not different from cats that were eating ad libitum. These findings support the idea that cats have only limited changes in the activity of hepatic TAT compared with rats. Total TAT activity was measured in cats fed high protein (550 g/kg) and low protein (180 g/kg) diets for 4 wk. Cats fed a high protein diet had activities significantly higher (about twice) than cats fed the low protein diet. Hepatic TAT activity of vitamin B-6-deficient cats (diet without pyridoxine for 9 wk) was compared with cats given the same diet with 8 mg pyridoxine/kg. Total hepatic TAT activity in deficient cats was significantly (P < 0.05) lower per gram soluble or total protein (but not per gram liver) than control cats; holoenzyme activity and percentage of active enzyme in deficient cats were also significantly lower by 75 and 64%, respectively. The apparent Km of TAT from cats for tyrosine (2.1 mmol/L) was similar to that for rats (1.9 mmol/L), but higher for PLP in cats (0.16 micromol/L) than rats (0.034 micromol/L). Part of the reason for the higher plasma tyrosine in vitamin B-6-deficient cats than rats is the higher Km of TAT for PLP in cats than rats.

Food selection by the domestic cat, an obligate carnivore

The domestic cat Felis silvestris catus is the most accessible member of the family Felidae for the study of the relationship between food selection and nutrition. In contrast to pack-living animals such as the dog, and opportunistic omnivores such as the rat, the cat is generally able to maintain its normal body weight even when allowed ad libitum access to palatable food by taking small meals and adjusting intake according to the energy density of the food(s) available. The most extreme adaptations to carnivory discovered to date lie in the taste buds of the facial nerve, which are highly responsive to amino acids and unresponsive to many mono- and disaccharides. Preferences for particular foods can be modified by their relative abundance, their novelty, and by aversive consequences such as emesis: the mechanisms whereby these are brought about appear to be similar to those used by omnivorous mammals.