Neonatal and pediatric care of the puppy and kitten.

Although the interval from birth to weaning is brief for dogs and cats, it is a very intensive period of adjustment to the extrauterine environment and preparation for the relatively greater independence of post-weaning. This rapid progression of events is preceded by critical developmental transitions, including organogenesis and parturition, and it is characterized by postparturient transitions that include the 3-4d neonatal period, the 21-28 maturation, and weaning itself. The purpose of this discussion is to characterize the primary events of these five transitional zones and to describe practical methods for evaluating progression through each transition, for establishing differential diagnoses, and for supportive actions and responses.

Differential diagnosis in archaeology.

Diagnosing archaeological bone specimens can be likened to practices used in medical and veterinary medical health care. Increasing the rigor of archaeological diagnosis can be supported by a systematic approach derived from health care settings. The process of information synthesis and diagnosis can be viewed as being very similar among these disciplines. A first diagnostic step is developing an Initial Information Set (sometimes called an Initial Database in health care environments) from descriptive data about the archaeological specimen or the patient, accompanied by recording environmental and ecological observations. The second diagnostic step is to develop an Expanded Information Set that includes structured physical examination, constructing a problem list, and considering potential differential diagnoses for each recorded problem. Subsequently, a Diagnostics Information Set consists of outcomes of carefully selected diagnostic testing, and a Diagnostic Assessment is developed from an orderly mental synthesis of information across Information Sets. Critical aspects of a structured and orderly process are preparing inclusive differential diagnoses, thorough mental synthesis across Information Sets, and recognizing that a short list of the most plausible diagnostic alternatives may represent the furthest possible extent of the evaluation for many archaeological bone specimens.

Granular media filtration: old process, new thoughts.

The design of granular media filters has evolved over many years so that modern filters have larger media sizes and higher filtration velocities than in earlier times. The fundamental understanding of filtration has also improved over time, with current models that account reasonably for all characteristics of the media, the suspension and the filter operation. The methodology for design, however, has not kept pace with these improvements; current designs are based on pilot plants, past experience, or a simple guideline (the ratio of the bed depth to media grain size). We propose that design should be based universally on a characteristic removal length, with the provision of a bed depth that is some multiple of that characteristic length. This characteristic removal length is calculated using the most recent (and most complete) fundamental model and is based on the particle size with the minimum removal efficiency in a filter. The multiple of the characteristic length that yields the required bed depth has been calibrated to existing, successful filters.

Particle detachment during hydraulic shock loads in granular media filtration.

Particle breakthrough can occur by either the breakoff of previously captured particles (or flocs) or the direct passage of some influent particles through the filter. Filtration experiments were performed in a laboratory-scale filter using spherical glass beads with a diameter of 0.55 mm as collectors. A single type of particle suspension (Min-U-Sil 5) and three different destabilisation methods (pH control, alum and polymer destabilisation) were used to destabilise particles. The filtration velocity of 5 m/h was similar to that used in standard media filtration practice. To assess the possibility of particle detachment during normal filtration, a hydraulic shock load (20% increase of flow rate) was applied after 4 h of normal filtration. The magnitude of particle detachment was proportional to the particle size for non-Brownian particles. At the same time, less favourable particles, i.e. particles with larger surface charge, were easily detached during the hydraulic shock load. Therefore, proper particle destabilisation before filtration is crucial for maximum particle removal, as well as minimum particle breakthrough.

Investigation of membrane fouling in ultrafiltration using model organic compounds.

Natural organic matter (NOM) is known to be the worst foulant in the membrane processes, but the complexities of NOM make it difficult to determine its effects on membrane fouling. Therefore, simple organic compounds (surrogates for NOM) were used in this research to investigate the fouling mechanisms in ultrafiltration. Previous research on NOM components in membrane processes indicated that polysaccharides formed an important part of the fouling cake. Three polysaccharides (dextran, alginic acid, and polygalacturonic acid) and a smaller carbohydrate (tannic acid) were evaluated for their removal in softening (the treatment process in the City of Austin). Two polysaccharides (dextran and alginic acid) were selected and further investigated for their effects on membrane fouling. The two raw organic waters (4 mg/L C) showed quite different patterns of flux decline indicating different fouling mechanisms. Softening pretreatment was effective to reduce flux decline of both waters. The SEM images of the fouled membrane clearly showed the shapes of deposited foulants. The high resolution results of the XPS spectra showed substantially different spectra of carbon, C(1s), in the membrane fouled by two raw organic waters. The XPS was beneficial in determining the relative composition of each fouling material on the membrane surface.

The influence of age on the canine immune system.

Immune function was assessed in a group of 47 Labrador Retrievers, ranging in age from 0.8 to 11.5 years, in order to establish baseline data on canine immunosenescence. Natural killer cell activity, lymphocyte subset distributions, antibody production, and mitogen-induced lymphoproliferative responses, all of which have been demonstrated to undergo age-related changes in humans and mice, were chosen as indicators of immune function. Dogs were categorized by age as young (mean 2.4 years), middle-aged (mean 5.8 years), and old (mean 9.1 years). Natural killer cell activity was not affected significantly by age. Lymphocyte subset analysis revealed a significant age-related increase in the percentage of cells staining with a pan T-cell reagent, accompanied by a corresponding increase in the percentage of CD8 cells from youth to middle age. An age-related decrease in the percentage of B-cells was observed concomitant with the increases in T-cell percentages. A gender-related difference in pan T-cell distribution was also observed, with females having a higher percentage than males. Lymphoproliferative responses of both young and middle-aged dogs to the mitogens concanavalin A, phytohemagglutinin, pokeweed mitogen, and staphylococcal enterotoxin B were significantly higher than those of old dogs. In general, the mitogen responses of male dogs were affected more dramatically by age than those of females. A significant age-related decline in in vivo antibody responses to the protein antigen, keyhole limpet hemocyanin, was not observed, although the mean titers of the young dogs were higher than those of the old.

The influence of age and gender on the immune system: a longitudinal study in Labrador Retriever dogs.

While aging studies employing a cross-sectional design have been informative in documenting many age-related alterations in immune function between different age cohorts within a population, longitudinal studies are invaluable for verifying changes at the level of the individual and for defining the precise periods of life during which particular changes occur. In the present study, a battery of immunological parameters were evaluated in a group of Labrador Retrievers as part of a comprehensive longitudinal aging study. Twenty-three dogs (14 females, 9 males; from 4 to 11 years of age) were evaluated annually for total WBC counts, lymphocyte subset distributions, natural killer cell activity and neutrophil phagocytic activity, and biannually for lymphoproliferative activity. An age-related decline in absolute numbers of lymphocytes, T-cells, CD4-cells and CD8-cells was observed in both genders. The distribution of lymphocyte subsets shifted with age, most dramatically in the females; percentages of B-cells declined while those of T-cells increased. Changes in percentages of CD4- and CD8-cells over the 8-year period were not dramatic; in females, percentages of CD8-cells increased significantly in early- to mid-life and then stabilized. Lymphoproliferative responses to mitogens declined over time in both genders. Males demonstrated higher levels of NK cytolytic activity than females; a marginal decline in activity with age was observed. No significant age-related changes in the phagocytic capacity of PMN were observed. These longitudinal findings help to discriminate between those immune parameters which change most dramatically in early-life versus those which either change more dramatically later in life or change gradually over the entire span of life. In addition they identify significant gender differences in several parameters and corroborate our previously published cross-sectional aging data in the same species.

Multiple hepatic cavernous lymphangioma in an aged male cat.

A 10-year-old male Domestic Longhair cat with weight loss, enlarged left testicle, icterus and mild liver enlargement showed, at necropsy, two white, raised, firm, circumscribed masses in the liver and striking enlargement of the left testicle. The histological features of the liver masses were consistent with lymphangioma. Severe, diffuse, coalescing to multifocal, subacute, necrotizing orchitis of the left testicle also was diagnosed. A literature review and examination of the epidemiology of lymphangioma in small domestic animals demonstrated the rarity of this tumour in cats.

Chemoattractant properties of conditioned medium from equine corpora lutea collected at various stages of the oestrous cycle.

This study investigated the chemotactic activity of equine CL at different stages of the oestrous cycle. The purpose of this was to ascertain whether luteal tissue itself contributes to the massive influx of leucocytes around the time of natural and induced luteal regression. Corpora lutea were collected at different stages of dioestrus and after treatment with PGF2alpha. Culture medium harvested after incubation of luteal tissue for 20 h was chemotactic for both polymorphonuclear and mononuclear cells in late dioestrus (before functional regression) as well as after natural and induced luteal regression. By contrast, midluteal tissue showed no chemotactic activity. This is the first report of the ability of equine luteal tissue actively to recruit inflammatory cells in vitro and supports our earlier findings that this infiltration starts prior to functional luteolysis. We hypothesise that this early influx of inflammatory cells may play an active role in luteal regression. Further research is needed to identify the specific chemotactic factor(s).

Evidence for genetic involvement in feline dilated cardiomyopathy.

Quantitative genetic evaluation of clinical dilated cardiomyopathy (DCM) was conducted in a large cattery with known history. Data showed that clinically affected cats were significantly more interrelated than randomly chosen case-control populations from the same colony. The results of this study suggest that quantitative inheritance, either interactive with or independent of nutrition or presently unknown factors, is involved in feline dilated cardiomyopathy.

Morbidity and mortality in neonatal kittens.

The mortality patterns of 294 Domestic Shorthair kittens indicated that birth weight was closely related to survivability. Slightly over half of the nonsurviving kittens lost at 0 to 3 days of life were stillborn. Abnormal gross anatomy did not appear to be a major factor in neonatal kitten death. Mortality was lowest at the 5th parity and in litters of 5 kittens. Litters of 1 kitten experienced high mortality. Smaller queens tended to deliver fewer kittens per litter, but with improved kitten viability. Overweight queens experienced increased mortality of kittens. Further examination of mortality by litter size also revealed that low birth weight kittens tended to survive less often than normal birth weight kittens, even within the same litter.

Laparoscopic sterilization of the bitch and queen by uterine horn occlusion.

Laparoscopic sterilization techniques, originally developed for use in women, were evaluated in the bitch and queen. In the first study (study I), the uterine horns of 6 bitches and 3 queens were occluded by electrocoagulation or plastic clips. The sites of occlusion were midway along the length of 1 cornus and at the uterotubal junction on the contralateral side. Both procedures effectively occluded the uterine horns, as evidenced by a distinctly visible separation of the reproductive tract. Laparoscopic examination 1 year after surgery revealed an enlarged, thin-walled, and fluid-filled uterine segment cranial to the midcornus occlusion sites in all animals. The contralateral horn was normal in appearance, except for the separation from the ovarian bursa. Three of the bitches developed pyometra (confined to the distended uterine segment) at 24 months, at 53 months, and at 72 months after sterilization, respectively. In a subsequent study (study II), 1 adult and 5 prepubertal bitches were sterilized by laparoscopic electrocoagulation of both uterine horns at the uterotubal junction adjacent to the ovarian bursa. Upon reexamination 1, 2, and 4 years later, the uterine horns of these females were normal in appearance, but were separated from the adjacent ovarian bursae. These females continued to be clinically healthy. Laparoscopic sterilization offers a rapid and safe alternative to ovariohysterectomy and, because of its minor invasive nature, can be performed on young, prepubertal animals. Such a procedure may have particular value as a simple, practical means of sterilizing dogs and cats on a mass basis.

Effects of age, sex, and body size on serum concentrations of thyroid and adrenocortical hormones in dogs.

Thyroxine (T4), 3,5,3'-triiodothyronine (T3), and cortisol frequently are quantified in canine serum or plasma samples to aid in the diagnosis of hypothyroidism, hypoadrenocorticism, and hyperadrenocorticism. Many laboratories have established reliable references values for concentrations of these hormones in blood of clinically normal animals. However, nonpathologic factors that affect thyroidal and adrenocortical secretion may lead to misinterpretation of test results when values for individual animals are compared with reference values. The objective of the study reported here was to identify effects of age, sex, and body size (ie, breed) on serum concentrations of T3, T4, and cortisol in dogs. Blood samples were collected from 1,074 healthy dogs, and serum concentrations of the iodothyronines and cortisol were evaluated for effects of breed/size, sex, and age. Mean (+/- SEM) serum concentration of T4 was greater in small (2.45 +/- 0.06 micrograms/dl)- than in medium (1.94 +/- 0.04 micrograms/dl)- or large (2.03 +/- 0.03 micrograms/dl)-breed dogs, the same in females (2.11 +/- 0.04 micrograms/dl) and males (2.08 +/- 0.04 micrograms/dl), and greater in nursing pups (3.04 +/- 0.05 micrograms/dl) than in weanling pups (1.94 +/- 0.05 micrograms/dl), rapidly growing dogs (1.95 +/- 0.04 micrograms/dl), and young adult (1.90 +/- 0.06 micrograms/dl), middle-aged adult (1.72 +/- 0.05 micrograms/dl), or old adult (1.50 +/- 0.05 micrograms/dl) dogs. Dogs greater than 6 years old had lower mean serum T4 concentration than did dogs of all other ages, except middle-aged adults. Mean serum T3 concentration in medium-sized dogs (1.00 +/- 0.01 ng/ml) was greater than that in small (0.90 +/- 0.01 ng/ml)- and large (0.88 +/- 0.01 ng/ml)-breed dogs.(ABSTRACT TRUNCATED AT 250 WORDS)

Histopathologic features, environmental factors, and serum estrogen, progesterone, and prolactin values associated with ovarian phase and inflammatory uterine disease in cats.

Forty-four female American Shorthair cats with inflammatory uterine disease or infertility were evaluated. Data collected included age, month of diagnosis, housing, reproductive history, results of bacteriologic culture of uterine specimens, serum concentrations of estrogen, progesterone, and prolactin and histopathologic features of the ovaries and uterus. Histologically, the ovaries of 19 cats were dominated by active or cystic follicles, whereas 25 cats had luteal-phase ovaries. Of the 25 cats with active corpora lutea, 20 had either recently weaned litters (n = 11) without subsequent exposure to a male cat, or had been housed individually for lengthy periods (n = 9). The finding of active corpora lutea under these circumstances indicates that in queens, ovulation may occur by mechanisms not involving coitus. Prominent, active corpora lutea on the ovaries were associated with adenomatotic proliferative changes in the superficial and glandular epithelium of the uterus and with myometrial hyperplasia, compared with the uterus of cats with follicular ovaries (P less than 0.01). Serum progesterone concentration greater than or equal to 1.87 ng/ml was consistently associated with luteal-phase ovaries. Serum progesterone values less than or equal to 0.15 ng/ml were consistently associated with follicular-phase ovaries. Escherichia coli was the organism most commonly isolated from uterine contents.

Within- and between-examiner repeatability of distraction indices of the hip joints in dogs.

OBJECTIVE: To evaluate in vivo repeatability of the distraction index method of evaluating hip joint laxity in dogs. ANIMALS: 31 two-year-old Labrador Retrievers. PROCEDURE: Each dog was anesthetized and radiographically evaluated for hip joint laxity 4 times: twice by an experienced examiner and twice by an examiner who had no previous knowledge of or training in the technique prior to the first day of testing. Distraction indices (DI) were determined from the radiographs and intraclass correlation coefficients were calculated to evaluate the repeatability of DI measurements between and within examiners. RESULTS: Intraclass correlation coefficients were high (range, 0.85 to 0.94). Lower limits of the 95% confidence intervals for the intraclass correlation coefficients ranged from 0.75 to 0.89. CONCLUSIONS: Between- and within-examiner repeatabilities of DI measurements were high, suggesting that the technique is clinically reliable. CLINICAL RELEVANCE: Distraction index is a reliable measure of hip joint laxity and a good predictor of the risk of development of degenerative joint disease associated with hip dysplasia in dogs. Establishment of high repeatability of DI measurements suggests that the stress-radiographic method may be used by multiple examiners with the expectation of comparable and consistent results.

Benign familial hyperphosphatasemia in Siberian huskies.

OBJECTIVE: To evaluate benign familial hyperphosphatasemia involving serum alkaline phosphatase (SAP) in pups. DESIGN: Pups with markedly increased SAP activity were evaluated and compared with unaffected siblings, and with other unaffected Siberian Husky pups from the same colony. ANIMALS: 8 related litters of Siberian Husky pups (n = 56). PROCEDURE: At ages 11 and 16 weeks, pups were given physical examinations and blood was obtained for hematologic and serum biochemical analyses (including electrolytes and isoenzymes of alkaline phosphatase), ionized calcium concentration, and serum parathyroid hormone concentration. Diet, growth and health performance, skeletal radiographs, and genealogical data also were evaluated. RESULTS: Of 42 pups tested, 17 had markedly high total SAP values. Mean total SAP activity of affected pups at ages 11 and 16 weeks was over 5 times greater than mean total SAP activity of unaffected siblings and other unaffected Siberian Husky pups of the same age (P < 0.001). Clinical, radiologic, and biochemical evaluation of the subjects revealed no other abnormal findings. The source of the increased SAP activity was characterized in 5 affected pups as bone isoenzyme. The mode of inheritance could be deduced from the data, but the trait clearly is familial and autosomal. CONCLUSION: The condition described in the family of Siberian Huskies bears similarity to human benign, persistent, familial hyperphosphatasemia. CLINICAL RELEVANCE: Benign familial hyperphosphatasemia should be considered in the differential diagnosis of markedly increased SAP activity in young dogs.

Influence of restricted food intake on estrous cycles and pseudopregnancies in dogs.

OBJECTIVE: To examine effects of restricted food intake on estrous cycle frequency, interestrus interval, and pseudopregnancy prevalence in dogs. ANIMALS: 28 female Labrador Retrievers. PROCEDURE: Dogs were paired by body weight when they were 6 weeks old and fed so that the limit-fed pair-mate received 75% of the amount of food offered to its maintenance-fed counterpart. Estrous cycle, interestrus interval, and pseudopregnancy data were recorded. RESULTS: Mean annual frequency of estrous cycles and duration of interestrus intervals did not differ between feeding groups. Prevalence of clinically evident pseudopregnancy was significantly greater among females that were maintenance fed, although results of endocrinologic testing did not identify a mechanism for this observation. CONCLUSIONS AND CLINICAL RELEVANCE: Pseudopregnancy in dogs can be influenced by physiologic factors related to nutrition. Clinicians should consider a variety of physiologic and environmental factors when evaluating reproductive function in dogs.

Effects of dietary electrolyte balance on subluxation of the femoral head in growing dogs.

Effects of increased dietary chloride and reduced sodium and potassium ion concentrations on coxofemoral joint conformation, as assessed by radiography, were examined in growing dogs. Dietary electrolyte balance was quantified by dietary anion gap (DAG), defined as Na+ + K+ - Cl- in milli-equivalents per 100 g of food. Diets had anion gap ranging from 8 to 41 mEq/100 g of food. One hundred sixty-seven pups from 27 litters representing 5 breeds were studied during the period of rapid growth. The extent of subluxation of the femoral head was measured on radiographs, using the method of Norberg. On average, less subluxation of the femoral head (P < 0.05) was observed when diets with lower DAG were fed. Differences in DAG balance did not result in different rates of weight gain; therefore, the reduction in coxofemoral joint subluxation attributable to low DAG was unrelated to weight gain. Norberg angles measured at 30 weeks of age were highly correlated with coxofemoral joint status at 2 years of age, as measured by the Swedish diagnostic system and the scoring system of the Orthopedic Foundation for Animals (lrl > or = 0.70, P < 0.0002, n = 24). This diet-related improvement in coxofemoral joint subluxation would be expected, on average, to delay or mitigate the characteristic clinical and radiographic signs of hip dysplasia in growing dogs.

Five-year longitudinal study on limited food consumption and development of osteoarthritis in coxofemoral joints of dogs.

OBJECTIVE: To examine the effects of limited food intake on frequency and severity of osteoarthritis in coxofemoral joints of labrador Retrievers. DESIGN: Dogs were paired according to gender and body weight, within each litter at 8 weeks of age. One dog of each pair was fed ad libitum. The limit-fed pairmate was fed 75% of the amount eaten the previous day by the ad libitum-fed counterpart. ANIMALS: 48 Labrador Retrievers. PROCEDURE: All dogs received the same diet. Radiographic evaluation of coxofemoral joints for frequency and severity of osteoarthritis were made when dogs were 4 and 6 months and 1, 2, 3, and 5 years old. RESULTS: Radiographic evaluation for osteoarthritis indicated greater frequency and more severity of osteoarthritis in the ad libitum-fed group of dogs. CLINICAL IMPLICATIONS: Analysis of data suggested that limit feeding of dogs over a 5-year period minimizes development of osteoarthritis in the coxofemoral joints.

Effects of limited food consumption on the incidence of hip dysplasia in growing dogs.

Forty-eight 8-week-old Labrador Retrievers were allotted to 2 groups of 24 dogs each; 1 group was fed ad libitum and the other group was given 25% less of the same feed until the dogs were 2 years old. Radiography of the hip joints was done when the dogs were 30, 42, 54, 78, and 104 weeks old. Subluxation was measured by the Norberg angle on radiographs made with the dog in the standard (extended limb) position. Independent of age at which the radiography was done, there was less subluxation of the femoral heads in the limit-fed dogs. Using the Swedish method of hip joint evaluation on the same radiographs, it was found that fewer dogs on limited food intake had signs of hip dysplasia. Radiographs done when dogs were 2 years old, for all the methods used (Norberg angle in standard and frog-limb position, the Orthopedic Foundation for Animals [OFA] score, and the Swedish score), revealed less hip dysplasia (less joint subluxation and less degenerative joint disease) in the limit-fed dogs. Using the OFA method, 7 of the 24 limit-fed dogs and 16 of the 24 ad libitum-fed dogs were diagnosed as having hip dysplasia. Similarly, using the Swedish method, 5 of the 24 limit-fed dogs and 18 of the 24 ad libitum-fed dogs were diagnosed as having hip dysplasia. The food-intake-related differences were significant both for the OFA score and for the Swedish score.(ABSTRACT TRUNCATED AT 250 WORDS)