Effects of supplementation of whole corn germ on reproductive performance, calf performance, and leptin concentration in primiparous and mature beef cows

A 2-yr study using primiparous and multiparous, spring-calving, crossbred beef cows was conducted to evaluate the effects of supplemental whole corn germ on reproductive performance, calf performance, and serum leptin concentrations. Each year, cows were blocked by age and BCS and assigned randomly to one of three treatments: PRE (n = 115) cows received 1.14 kg/d (DM basis) of whole corn germ for approximately 45 d before calving; POST (n = 109) cows were fed 1.14 kg/d of whole corn germ for approximately 45 d after calving; and control cows (n = 118) were fed similar energy and protein from dry-rolled corn (1.82 kg of DM/d) for 45 d before and after calving. Additionally, PRE cows were grouped with controls after calving, and POST cows were grouped with control cows before calving, so that corn germ-supplemented cows received the control supplement in the alternate feeding period. Cow BW (538 +/- 13 kg) and BCS (5.4 +/- 0.13) did not differ among treatments at any time during the experiment. Calf birth weight (39 +/- 2 kg), weaning weight (225 +/- 7 kg), and age-adjusted weaning weight (234 +/- 8 kg) did not differ because of dam supplementation regimen. Treatment did not affect the proportion of cows exhibiting ovarian luteal activity before the start of the breeding season (67%) or pregnancy rate (91%). The interval from exposure to bulls until subsequent calving did not differ (P = 0.16) among PRE (298 +/- 2.3 d), POST (303 +/- 2.6 d), and control (304 +/- 2.3 d) cows. Leptin concentrations did not differ among treatments and were 2.15 +/- 0.75, 1.88 +/- 0.76, and 1.91 +/- 0.75 ng/mL for control, POST, and PRE cows, respectively. Age and week relative to calving influenced leptin concentration. Primiparous cows had similar leptin concentrations to 3-yr-old and mature cows for wk -7 and -6 relative to calving, but lower (P < 0.10) concentrations than mature cows for wk -5, and lower (P < 0.05) concentrations than either 3-yr-old or mature cows for wk -4 to +7 relative to calving. Serum leptin was correlated with BCS (P < 0.0001; r = 0.35) at initiation of the feeding period and was correlated with BCS (P = 0.02; r = 0.12) and weight (P < 0.01; r = 0.14) at the completion of the supplement period, but it was not correlated with initial BW or interim BCS. Calving interval was not correlated (P > 0.12) with weekly measures of serum leptin concentration. Supplementing beef cows with whole corn germ had no effect on cow performance, calf performance, or serum leptin concentrations of cows.     

Relationship between total transit time and faecal quality in adult dogs differing in body size

Fed the same diet, large and giant-breed dogs have higher faecal moisture and increased frequency of soft stools than small ones. This could be the result of physiological differences, such as a different gastrointestinal transit time. In this study, we have correlated mean total transit time (MTT) with body size and faecal consistency in dogs varying in body size. Fifty dogs from 13 different breeds were used, from a Dachshund to a Great Dane. The MTT was determined using coloured plastic beads [Cummings and Wiggins, Gut, Vol. 17 (1976), p. 219], and faecal consistency was scored daily during the study. We confirmed the strong correlation between height at the shoulder (body size) and faecal score (r = 0.76; p < 0.0001). The MTT increased with body size, from 22 h for a Miniature Poodle to 59 h for a Giant Schnauzer. We found significant positive correlations (p < 0.0001) between MTT and body size as well as faecal scores (r = 0.71 and 0.70 respectively). In the present study, we observed an effect of body size on MTT. In our 50 healthy dogs a longer MTT was related to a poorer faecal quality. Previous studies reported no relationship between body size and the upper gastrointestinal transit time in healthy dogs. So, we hypothesized that body size would mainly affect colonic transit time and that a longer colonic residence time would be related to a poorer faecal quality by promoting fermentation activity.     

Key role of Chlamydophila psittaci on Belgian turkey farms in association with other respiratory pathogens

Two hundred turkey sera from eight Belgian and two French farms were tested for the presence of antibodies against avian pneumovirus (APV), Ornithobacterium rhinotracheale (ORT), Mycoplasma gallisepticum, Mycoplasma meleagridis and Chlamydophila psittaci. At slaughter, C. psittaci, APV and ORT antibodies were detected in 94, 34 and 6.5% of the turkeys, respectively. No antibodies against M. gallisepticum or M. meleagridis were present. Additionally, turkeys on three Belgian farms were examined from production onset until slaughter using both serology and antigen or gene detection. All farms experienced two C. psittaci infection waves, at 3-6 and 8-12 weeks of age. Each first infection wave was closely followed by an ORT infection starting at the age of 6-8 weeks, which was still detectable when the second C. psittaci infection waves started. Animals on farm A were not vaccinated against APV leading to an APV subtype B outbreak accompanying the first C. psittaci infection wave. Despite subtype A APV vaccination on farms B and C, the second C. psittaci infection waves were accompanied (farm B) or followed (farm C) by a subtype B APV infection. On all farms respiratory signs always appeared together with a proven C. psittaci, APV and/or ORT infection. This study suggests an association between C. psittaci, APV and ORT, and indicates the multi-factorial aetiology of respiratory infections in commercial turkeys. All three pathogens should be considered when developing prevention strategies for respiratory disease.     

The detection and characterisation of Dichelobacter nodosus from cases of ovine footrot in England and Wales

Footrot, caused by the strictly anaerobic bacterium Dichelobacter nodosus, is the most common cause of lameness in sheep in Great Britain but problems exist in association with its diagnosis and control. The fastidious nature of D. nodosus means that complex media and several weeks are required for characterisation. An alternative method to simplify and enhance the detection of D. nodosus in clinical samples is therefore highly desirable. In terms of control, anecdotal evidence from the farming community suggests that the commercially available vaccine, based on Australian isolates of D. nodosus, is not widely employed in this country due to its perceived inefficacy. Seven hundred and six isolates, collected from outbreaks in England and Wales, were therefore used to investigate these issues. A 16S rRNA PCR was adapted to detect D. nodosus in clinical material within 1 day of sampling; a 15% increase in detection compared with culture and less than 1% false negatives were achieved. This represents a major advance in the rapid diagnosis of footrot and will be of great value to practitioners and diagnostic laboratories. Bacterial virulence was tested using protease thermostability and zymogram assays, whilst serogrouping was performed by slide agglutination. All isolates demonstrated virulence patterns previously recorded in Australia and all nine serogroups of D. nodosus (A-I) were represented. Serogroup H was predominant. There was, therefore, no evidence for the presence of novel strains of D. nodosus compared with Australia suggesting the need for further investigation into farmers' views on the use of the commercial vaccine in Great Britain.     

CLINICAL ASSESSMENT OF RENAL FUNCTION IN THE DOG WITH A REDUCTION IN NEPHRON NUMBER*

The viewpoint presented is that, because compensatory functional adjustment of the residual nephrons occurs in chronic renal disease, reduction in nephron number usually exceeds 70% before a diagnosis is made. The case that earlier diagnoses are likely if laboratory medicine values are measured and interpreted with a maximum of efficiency is then made. The laboratory data more commonly used in practice for the clinical assessment of renal function in the dog are presented and some comparisons with findings in man are made. The information originates from clinical and experimental observations of the authors, as well as from a literature review. The laboratory data presented and discussed includes glomerular filtration rate and the clearance of nitrogenous waste (urea and creatinine), plasma protein concentration, plasma osmolality, renal concentrating capacity, and urinary constituents, particularly its protein concentration and sediment (centrifuge deposit). All parameters recommended for the clinical assessment of chronic renal failure are considered qualitatively, and some are also dealt with quantitatively.     

RESPONSE OF CATTLE TO INOCULATION WITH ATYPICAL MYCOBACTERIA ISOLATED FROM SOIL

Nine strains of atypical mycobacteria and a strain of the rhodochrous taxon, originally isolated from soil samples collected on the subcoastal plains of the Northern Territory, were inoculated into cattle. Each strain was injected subcutaneously into one animal and into a mesenteric lymph node of another. At 4 and 10 weeks after inoculation, the cattle were tuberculin tested with bovine PPD tuberculin, avian PPD tuberculin and the appropriate homologous PPD tuberculin. Six strains induced a significant level of sensitivity to bovine PPD at the 4-week test, but only one animal gave a similar response at the 10-week test. In general, the level of sensitivity to all tuberculins declined between the 4-week and 10-week tests. At both tests the response to avian PPD was equal to, or exceeded, that to bovine PPD. The inoculation of each of the 10 strains resulted in the production of tuberculous granulomas at the subcutaneous sites and similar lesions were produced at the mesenteric lymph node site in response to 2 strains. Mycobacteria were re-isolated from 11 cattle and represented 7 strains. The significance of the soil as a reservoir of atypical mycobacteria and other organisms capable of inducing sensitivity to bovine PPD is discussed.     

Aortic interruption in a dog.

A 3-month-old English Bulldog was found to have a discontinuity between the ascending and descending aorta. There were no signs of illness associated with the interruption. The descending aorta was supplied with blood by collateral circulation. An aortic graft of woven synthetic material was surgically implanted to connect the ascending and descending aorta. Without any restrictions on the dog's activity, the dog has lived for over 1 year and continues to do well.     

Incidence of liver haemorrhage among white leghorn strains fed on diets containing different types of rapeseed meals.

1. There was a marked strain difference in the incidence of hepatic haemorrhage in White Leghorn hens receiving dietary rapeseed meal (RSM). 2. Tolerance to high dietary contents of RSM also varied between individual birds within a strain. 3. Glucosinolates were implicated in the development of hepatic haemorrhage among hens receiving dietary RMS but the exact relationship was not clear.