Efficacy of an Extract from Garlic,Allium sativum,Against Infection with the Furunculosis Bacterium,Aeromonas salmonicida,in Rainbow Trout,Oncorhynchus mykiss

Juvenile rainbow trout, Oncorhynchus mykiss, were fed diets containing 0, 0.5, 1.0, and 2.0% of a garlic extract, challenged with a modified 50% lethal dose of Aeromonas salmonicida and monitored for 28 d. There were significant increases in survival of trout fed 0.5 and 1.0% garlic extract as compared to the control and 2.0% garlic extract groups. A target animal safety study was performed at varying increments using the target dose of 0.5% garlic extract at 0× (0% garlic extract), 1× (0.5% garlic extract), 3× (1.5% garlic extract), and 5× (2.5% garlic extract) for 3× (6 wk) the duration of the original study. There was a significant increase in the level of circulating lymphocytes and a significant decrease in the level of circulating monocytes. The latter correlated to an increased level of pigment‐containing macrophage centers within the renal tissue as garlic extract dosing increased, denoting a potential deleterious inflammatory effect as macrophage infiltration became severe at the highest dose. These studies suggest that feeding low‐dose (0.5% or 1.0%) garlic extract improves survivability in rainbow trout when challenged with A. salmonicida and appears safe; however, higher levels do not appear to be effective and may cause deleterious effects on health.     

Milk production and lactation length in Ankole cattle and Ankole crossbreds in Rwanda

This study assessed daily milk yield (DMY), 100-day (MY100), and 305-day (MY305) milk yield, and lactation length (LL) in purebred Ankole cattle and Ankole crossbreds, and the influence of environmental factors on these traits. Milk yield data were obtained for 865 cows and 1234 lactations and analyzed using a mixed linear model. The overall least squares mean of DMY, MY100, and MY305 across breed groups was 2.7 L (N = 1234, SD = 1.7), 262 L (N = 959, SD = 176), and 759 L (N = 448, SD = 439), respectively, while the average lactation length was 256 days (N = 960, SD = 122). All factors included (breed group, season and year of calving, and parity) were significant for yield traits, except season of calving for MY305. First-parity cows had the lowest milk production, and fourth-parity cows the highest. For all traits, pure Ankole cows had the lowest milk yield. Among the crossbreds, there was no significant difference between Ankole × Friesian, Ankole-Jersey mother × Sahiwal sire, and Ankole-Sahiwal mother × Jersey sire, or between Ankole × Sahiwal and Ankole-Sahiwal mother × Sahiwal sire. It was concluded that Ankole crosses with Friesian or Jersey can be beneficial, even under a management system of limited nutrition as in Rwanda.

     

Influence of sow dietary fatty acid composition on the behaviour of the piglets

Polyunsaturated fatty acids (PUFA) are essential for the development of the nervous system in animals, and increased concentration of n−3 PUFA in maternal diet improves the cognitive development of mammalian foetuses. In this study the effect of maternal diet fatty acid composition in pigs on the development of the central nervous system, monitored as behaviour of piglets, was investigated using three behavioural tests: recognition of the mother's faeces, back test, and hidden door test.Twenty-seven multiparous Yorkshire sows were split into four groups and fed diets with different content of fat and PUFA throughout pregnancy and lactation. LF (n = 6) was fed a standard diet, HFS (n = 4) a high fat and low PUFA diet, HFO (n = 7) a high n−6 PUFA diet, and HFL (n = 10) a high n−3 PUFA diet.Three behavioural tests were performed on 5–7 randomly chosen piglets per litter (n = 167). Recognition of the mother's faeces was tested in a maze two days after birth. Back test was performed twice (2–4 d and 4 w) and a hidden door test was performed at 4 w. In addition, the brain content of docosahexaenoic acid (22:6 n−3, DHA) of the newborn piglets was determined in treatment groups. Data from the tests were analysed with linear mixed models for each of the tests.Piglets from HFL treatment had significantly higher content of DHA (P < 0.001) and the ratio of n−6/n−3 PUFA was significantly lower in brain tissue (P < 0.001), compared to piglets from the other treatments. In parity 3, means for recognition for mother's faeces were for diets LF, HFS, HFO and HFL; 22.2, 37.0, 26.4 and 18.0%, respectively (P < 0.05), but no other significant effect of diet was found. Piglets in HFS treatment had the shortest latency to make escape attempts and HFO piglets the longest latency in the back test (P = 0.030). No significant effect of sow diet was found on piglet performance in the hidden door test, but intermediate piglets weighing 1410–1619 g had a lower probability of success in hidden door test than piglets weighing < 1410 g (P = 0.028), and ≥ 1875 g (P = 0.027), respectively.It was found that sow diet influenced the DHA content in the piglet brains, but there was no clear effect of sow diet on piglet behaviour. In order to draw any conclusions about possible enhancements of the behavioural development of the piglet more studies need to be performed.     

Genetic Relations between Reproduction,Chick Weight and Maternal Egg Composition in a White Leghorn Line

Selection is a viable way to increase egg dry matter, an important trait for the egg processing industry, but simultaneously a change in the embryonic environment takes place. The main purpose of this study was to estimate genetic parameters for the percentage of fertile eggs of eggs set (FERT), percentage of eggs hatched of fertile eggs (HATCH), percentage of live chicks 2 weeks post-hatch of hatched eggs (SURV/h) and of fertile eggs (SURV), and their genetic correlations with egg weight, albumen weight, yolk weight, yolk proportion, albumen dry matter and mean chick weight in a White Leghorn selection line. Direct and maternal heritabilities were low for FERT, HATCH and SURV, and non-existent for SURV/h. All direct-direct genetic correlations between reproduction traits and egg composition traits were not significant. Maternal-direct genetic correlations between HATCH and egg weight, albumen weight, yolk weight, yolk proportion and albumen dry matter were - 0.22, - 0.30, 0.28, 0.52 and 0.26, respectively. Similar correlations were found between SURV and egg composition traits. No significant genetic relationship was found between chick weight and post-hatch survival. In conclusion, within the range of values for egg composition in this study, selection for an increased egg dry matter should not impair reproduction.     

Genetic Parameters for the Piglet Mortality Traits Crushing,Stillbirth and Total Mortality,and their Relation to Birth Weight

The aim of this study was to estimate genetic and phenotypic parameters for the three mortality traits crushing, stillbirth and total mortality in piglets, and their respective correlations with birth weight. Records were available from 11 016 Yorkshire piglets from 1046 first parity litters in a Swedish experimental herd. Each mortality trait was analysed jointly with birth weight, using bivariate models. Both mixed linear models and threshold models were used. The threshold models took environmental and maternal genetic effects into account, whereas the linear models also included a direct genetic effect of the piglet on its birth weight. The estimated heritabilities were low for all mortality traits (0.01-0.15), with the lowest estimate for crushing and the highest for stillbirth. The estimated environmental correlations between the different mortality traits and birth weight were negative. The estimated genetic correlations between crushing and birth weight (both direct and maternal effect) were also negative in both models, indicating that sows with low-weight piglets are more likely to crush piglets. However, the genetic correlations between stillbirth and birth weight (both direct and maternal effect) were positive. These results suggest that stillbirth and crushing are traits with different genetic backgrounds, and that genetically increasing the birth weight of the piglets may result in more stillborn piglets.     

Efficacy of selamectin in the treatment of nasal mite (Pneumonyssoides caninum) infection in dogs

In a laboratory study to evaluate the efficacy of selamectin for treatment of canine nasal mite infection, 12 purpose-bred beagles were experimentally infected with Pneumonyssoides caninum (P. caninum). Six of the dogs were treated with selamectin applied to the skin of the back at dosages of 6 to 24 mg/kg for three times at 2-week intervals. The remaining six dogs were an untreated control group. At necropsy 39 to 46 days after inoculation, no P. caninum mites were found in any of the treated dogs. In contrast, nasal mites were found in five of the untreated dogs. This difference was statistically significant at P=0.015.     

Reproductive performance of Ankole cattle and its crossbreds in Rwanda

Tropical Animal Health and Production - The aim of this study was to assess the reproductive performance of Ankole cattle and its crossbreds with Friesian (F), Jersey (J), and Sahiwal (S). The...     

Genetic correlations between gestation length, piglet survival and early growth

This study is based on 12708 first-parity and 7062 second-parity Yorkshire litters from Swedish nucleus herds; and on 1037 first-parity Yorkshire litters from an experimental herd. Gestation length was analysed together with litter size, piglet mortality and average piglet growth rate. A sire–dam model was used to estimate direct (litter) and maternal (sow) genetic effects. Direct heritability for gestation length was 0.3. Maternal heritability was estimated at 0.2 in nucleus data and 0.3 in experimental data. The maternal genetic correlation between gestation length and litter size was negative. The genetic correlations between gestation length and number stillborn were not consistent between the two data sets. Genetic correlations between gestation length and number dead after birth were negative. Genetic correlations between gestation length and average birth weight and piglet growth rate were positive. We conclude that gestation length is influenced by the genotype of the piglets and the genotype of the sow. Selection for prolonged gestation would probably improve piglet survival after birth and piglet growth; it might, however, result in more stillbirths.     

Morbidity of insured Swedish cats during 1999-2006 by age, breed, sex, and diagnosis

The aim of the study was to describe patterns of morbidity, as reflected by reimbursed claims for veterinary care among cats covered by a Swedish insurance company during 1999-2006. The annual incidence rates of having at least one veterinary care event were calculated overall and stratified by sex, age, breed, diagnosis and urban/other location. The total rate was 875 (95% CI 858-892) cats with claims per 10,000 cat-years at risk. The Siamese, Burmese, and the Abyssinians had high rates of claims, compared to the Norwegian Forest cat, the Maine Coon, the European Shorthair and domestic cats. The most common causes for insurance claims were trauma, gastrointestinal and lower urinary tract problems and there was substantial breed, sex and age variation for certain problems. For example, among cats under 9 years of age, the rate for lower urinary tract problems was 2-3 times higher in males than females.