Quantitative urinalysis in healthy Beagle puppies from 9 to 27 weeks of age

To evaluate indices of renal function in healthy, growing Beagle puppies from 9 to 27 weeks of age and to determine whether indices change with age during this period. Animals-6 healthy Beagle puppies. PROCEDURE: Urine collections were performed at 2-week intervals in puppies 9 to 27 weeks old. Daily excretion of urinary creatinine, protein, sodium, potassium, chloride, phosphorus, and calcium were determined, as were quantitative urinalyses including endogenous creatinine clearance, urine protein-to-creatinine ratios (UPr/C), and fractional clearances of sodium (FNa), potassium (FK), chloride (FCI), calcium (FCa), and phosphorus (FP). RESULTS: Significant differences among age groups were detected for endogenous creatinine clearance, and daily urinary protein, potassium, calcium, and phosphorus excretion. Significant differences also existed among age groups for UPr/C, FNa, FK, FCI and FP. Age-related effects fit a linear regression model for FNa, UPr/C, daily phosphorus excretion, and daily protein excretion. Quadratic regression models were judged most appropriate for endogenous creatinine clearance, FK, daily chloride excretion, and daily potassium excretion. Endogenous creatinine clearance measurements higher than adult reference ranges were observed from 9 to 21 weeks of age. The FNa, FK, FCI, FCa, and FP were slightly higher than those reported for adult dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Selected results of quantitative urinalyses in healthy 9- to 27-week-old Beagle puppies differ with age and differ from those measured in adult dogs. Diagnostic measurements performed in puppies of this age range should be compared with age-matched results when possible.     

Immunoglobulins in nasal secretions of dog puppies from birth to six weeks of age

In order to investigate local immune defence mechanisms in the dog, the concentration of immunoglobulins (Ig) G, A and M in nasal secretions (NS) and serum of 42 healthy, neonatal Rottweiler puppies was determined. Ig were measured with a commercially available, dog-specific ELISA during the first six weeks of life. On average, IgG was the predominant Ig isotype during the first three days of life. The IgA:IgG ratio changed between weeks 1 and 3 due to markedly decreasing IgG concentrations. Between the fourth and sixth week, IgG predominated again. During the first week, only 21-39% of puppies had measurable amounts of IgM in NS, in week 2, this percentage increased to 69%. Marked differences between litters and between individual puppies within litters were found. No puppy diseased during the observation period and all developed normally.     

Cage type and mineral nutrition had independent impact on skeletal development in Lohmann LSL-Lite pullets from hatch to 16 weeks of age

The effects of rearing cage type and dietary Ca, available P and vitamin D₃ (VitD₃) on body and skeletal development were studied. A total of 3,420 Lohmann LSL-Lite day-old chicks were reared in conventional (CON) or furnished cages (FUR) to 16 wk of age. Initially, 40 and 150 chicks/cage were placed in CON and FUR and transitioned to 20 and 75 chicks/cage at 8 wk of age, respectively. Three diets: Diet 1, Diet 1.5 and Diet 2 were formulated to meet nutrient specifications with Diet 1.5 and Diet 2 containing 1.5 and 2 times more Ca, P and VitD₃ than Diet 1, respectively. Diets were allocated within cage type to give 6 replicates and fed in 3 feeding programs: starter, grower and developer. At 4, 12 and 16 wk of age, BW was recorded, and femur, tibia and blood samples for bone quality and related parameters. There were no interactions (P > 0.05) of cage type, diet and pullet age on BW, plasma Ca and inorganic P, femur and tibia morphometry, mineral density (MD), breaking strength (BS) and ash concentration (AC). Concentration of Ca, P and VitD₃ linearly decreased BW (P < 0.001), relative femur (P = 0.010) and tibia weight (P = 0.013). A quadratic increase on femur MD (P = 0.03) and BS (P = 0.026) was observed with dietary concentration of Ca, P and VitD₃. Femur (P = 0.031) was longer for CON than FUR pullets, however, femur for FUR pullets had higher (P = 0.003) AC. Cage had no effect (P ≥ 0.415) femoral MD and BS. Pullets reared in FUR cages exhibited higher tibial MD (P = 0.015), BS (P = 0.071), AC (P < 0.01) and whole-body mineral content (P < 0.01). In conclusion, cage type and diets showed independent effect on femur and tibia quality with FUR pullets exhibiting enhanced indices of mineralization. Feeding pullets twice the recommended Ca, P and VitD₃ decreased BW, relative weight of leg bone but enhanced femoral strength with no effects on tibia attributes.     

Adrenocorticotropic hormone stimulation tests in healthy foals from birth to 12 weeks of age

The purpose of this study was to investigate total baseline plasma cortisol and adrenocorticotropic hormone (ACTH) concentrations, and ACTH-stimulated cortisol concentrations in foals from birth to 12 wk of age. Plasma (baseline) cortisol and ACTH concentrations were measured in 13 healthy foals at birth and at 1, 2, 3, 4, 5, 7, 10, 14, 21, 28, 42, 56, and 84 d of age. Each foal received cosyntropin (0.1 μg/kg) intravenously. Plasma cortisol concentrations were measured before (baseline), and 30, and 60 min after cosyntropin administration at birth and at 3, 5, 7, 10, 14, 21, 28, 42, 56, and 84 d of age. Compared with baseline, cortisol concentration increased significantly 30 min after administration of cosyntropin on all days. Cortisol concentration was highest at birth, measured at 30 and 60 min after cosyntropin administration, compared with all other days. With the exception of birth measurements, cortisol concentration was significantly higher on day 84, measured at 30 and 60 min after cosyntropin administration, when compared with all other days. Baseline plasma ACTH was lowest at birth when compared with concentrations on days 2, 3, 4, 5, 7, 10, 14, 42, 56, and 84. Administration of 0.1 μg/kg of cosyntropin, IV, reliably induces cortisol secretion in healthy foals. Differences in the magnitude of response to cosyntropin are observed depending on the age of the foal. These data should serve as a reference for the ACTH stimulation test in foals and should be useful in subsequent studies to evaluate the hypothalamic-pituitary-adrenal axis in healthy and critically ill foals.     

Valine requirements for immune and growth responses in broilers from 3 to 6 weeks of age

Four experiments were conducted to evaluate valine (Val) requirements in Ross 508 broilers from 3 to 6 weeks of age. Common diets were fed to broilers until 3 weeks of age. Growth and carcass measurements were taken in all experiments. Immune responsiveness measurements were taken in Experiments 1 and 2. Birds given 7.2 g Val/kg of diet in Experiment 1 had more abdominal fat than birds given 8.2 g Val/kg of diet, but there were no differences in growth or other carcass measurements. Because growth performance was not reduced in birds given 7.2 g Val/kg of diet, Val concentration was reduced to 6.4 g Val/kg of diet in Experiments 2 and 3. Increasing Val from 6.4 to 8.7 g Val/kg of diet resulted in linear increases for BW gain, feed efficiency and Val intake in male birds, and Val intake in female birds. Quadratic responses to increasing dietary Val were not observed in any experiment. There were no effects of Val on innate or adaptive immunity. A nonessential amino acid mixture containing the same nitrogen content as the L-Val additions in Experiment 4 was added and tends to support the idea that the responses to Val were specific and not due to increases in total nitrogen. Dose responses to Val resulted in male, but not female, birds given 7.3 g Val/kg of diet having improved BW gain and feed efficiency compared with birds receiving 6.4 g Val/kg of diet.     

Qualitative urinalyses in puppies 0 to 24 weeks of age

Suggestions for interpreting qualitative urinalyses from puppies have been based on limited results obtained in the laboratory setting. Proteinuria, glucosuria, and decreased concentration of urine have been considered normal in puppies <8 weeks of age due to immature renal function. In this study, the authors reviewed 149 voided urine samples from 118 different, apparently healthy, random-source puppies. The primary finding was that mean urine specific gravity (USG) was significantly lower in 0- to 3-week-old puppies when compared to puppies 4 to 24 weeks old. Mean USG in all other age groups was >1.030. There was no difference in the frequency of positive protein or occult blood dipstick results among age groups, and there were no positive glucose, ketone, bilirubin, or urobilinogen reactions in any samples analyzed. Urine sediment results are reported for 41 samples. Epithelial cells and white blood cells were the most common sediment findings in these 41 voided samples, observed in 34 (83%) and 18 (44%) samples, respectively. Crystals were observed in 15 (37%) samples, whereas casts, bacteria, and red blood cells were observed less commonly.     

Response of broiler chickens to fowl cholera vaccination at 1 to 6 weeks of age.

Broiler chickens, in groups of 10, received a single vaccination by the stick-wing route at 1, 2, 3, 4, 5, 6, or 11 weeks of age with live Clemson University strain of Pasteurella multocida. Twenty non-vaccinates kept in isolation served as controls. Cholera serum antibody titers in all chickens were determined by enzyme-linked immunosorbent assay at weekly intervals. Chickens vaccinated once at 1, 2, 3, 4, 5, and 6 weeks, respectively, attained 25.2%, 28.7%, 34.7%, 46.2%, 51.8%, and 64.6% of the titers of those vaccinated once at 11 weeks of age. Variation in antibody response was greatest in chickens vaccinated at 1 or 2 weeks of age. Additionally, chickens vaccinated at 1 or 2 weeks of age showed the longest response time (5 weeks) to reach maximum antibody titers after a single vaccination. When the original vaccinates were revaccinated at 11 weeks of age, all showed a secondary response equal to or greater than that seen in chickens vaccinated once at 11 weeks of age. Age of the chickens at the time of vaccination and antibody titer were positively correlated (r = 0.997). Overall antibody responses to vaccination were higher and much more uniform as birds increased in age.     

Intake energy, energy retention and heat production in lambs from birth to 24 weeks of age

Intake energy (IE), metabolizable energy intake (MEI), energy retention (ER) and heat production (HP) were estimated in twelve male and six female suckling lambs from birth to 4 wk of age and in nine of these male lambs after weaning from 9 to 24 wk of age. Intake energy and MEI were estimated from the milk intake and combustible energy of the milk in the suckling lambs and from digestibility trials and energy content of feed and feces in the weaned lambs. Energy retention was estimated from body composition changes and HP was calculated from MEI - ER and from the rate of O2 consumption. The O2 consumption of the ewes was also measured during late pregnancy and during lactation. In the suckling lambs, daily MEI was 277 kcal/kg.75 and ER was 112 kcal/kg.75 and as calculated from O2 consumption was 168 kcal/kg.75. Daily HP as calculated by MEI - ER was 165 kcal/kg.75. Daily maintenance HP was equal to 121 kcal/kg.75 and the efficiency of utilization of energy for ER was 70.7%. In the weaned lambs, HP as measured from O2 consumption was 10% lower than that estimated using MEI and ER. Comparison of 9- to 16-wk-old with 17- to 24-wk-old lambs, showed daily increases in MEI from 212 to 228 kcal/kg.75, in ER from 54 to 95 kcal/kg.75 and in HP from 158 to 194 kcal/kg.75, whereas there was a daily decrease in maintenance HP from 101 to 90 kcal/kg.75. Efficiency of utilization of energy for production was similar in the two postweaning periods (48.8 and 46.5%, respectively). The O2 consumption of the ewes (/kg.75) was increased over that of nonpregnant, nonlactating controls by 30% in late pregnancy, by 62% in the first month of lactation and by 50% in the second month of lactation.     

Strongylus edentatus: development and lesions from ten weeks postinfection to patency.

Pony foals inoculated with infective Strongylus edentatus larvae were examined at necropsy from ten to 72 weeks postinfection. At ten weeks postinfection larvae were visible retroperitoneally in the liver and flanks and were recovered from the ligaments of the liver. The fourth molt was detected at 16 weeks postinfection and larvae were also recovered from the wall of the cecum at this time. By 40 weeks adult S. edentatus containing eggs were found in the contents of the cecum and colon. While many larvae migrate to remote parts of the body, it is likely that only those that attain the base of the cecum are successful in establishing in the cecum and colon as adult forms. By 36 weeks postinfection no larvae were found in the liver and up to this time none were found in the peritoneal cavity. Larvae were not recovered from the parenchyma of the lungs. Adhesions and disruption of omental architecture were frequent changes observed throughout infection. Casts of necrotic eosinophils enclosing tracks and larvae were observed beneath the intima of major veins of the cecum and colon. The liver was rough and the capsule thickened at 16 and 20 weeks postinfection and the flanks remained edematous until 36 weeks postinfection.     

Short-term effects of prepubertal ovariohysterectomy on skeletal, physical and behavioural development of dogs up to 24 weeks of age

This study investigated the effects of ovariohysterectomy performed at 10 weeks of age on body weight, behaviour, bone length, serum calcium and phosphorus concentrations and gonadal hormone (progesterone and oestradiol) levels until 24 weeks of age in 31 clinically healthy mixed-breed female puppies. The littermates were randomly assigned to three groups. Group I (n=11) was completely ovariohysterectomised, Group II (n=10) was incompletely ovariohysterectomised with one ovary left intact, and Group III (n=10) was sham operated. No significant differences were found between the groups for any of the parameters evaluated. It was determined that, except for two measurements of two animals in Group II at 20 and 24 weeks of age, all animals had undetectable concentrations of oestradiol 17-beta. These findings suggest that an ovariohysterectomy performed on a mixed-breed dog at 10 weeks of age does not affect her skeletal, behavioural or physical development in the period studied, i.e. until 24 weeks of age.     

The effect of photoperiod on performance of female turkeys from two to 16 weeks of age

1. Female turkeys were subjected, from 2 to 16 weeks of age, to four lighting treatments, 23 h/d, 14 h/d, 8 h/d and a “step‐down” pattern in which light was reduced from 22 h/d by 1 h per week to 14 h/d.

2. Within each lighting treatment half the groups were offered food ad libitum and half received the same restricted amounts of food on all lighting treatments.

3. There were no significant differences in final body weight or food conversion efficiency (FCE) between photoperiod treatments. FCE was superior in restricted groups (P<0.05).     

The effect of photoperiod on performance of male Turkeys from 2 to 15 weeks of age

1. Two‐week‐old male turkeys were subjected, for 13 weeks, to four lighting treatments, 23 h/d, 14 h/d, 8 h/d, and a “step‐down” pattern in which light was reduced from 22 h/d by 1 h a week to 14 h/d.

2. Within each lighting treatment half the groups were offered food ad libitum and half received restricted amounts of food which were similar for all lighting treatments.

3. There were no statistically significant differences in final body weights or food conversion ratios between photoperiod treatments, although within groups fed ad libitum food conversion ratio was slightly superior for turkeys which had received 23 h light/d throughout.