Optic neuropathy in sheep associated with overdosage of closantel

This report describes clinical and pathological findings in 2 flocks in Brazil where blindness and deaths in sheep occurred after closantel overdosage. Depression, weakness, and blindness affected 37 animals and 17 died in 2 flocks of 190 animals. Two animals submitted for ophthalmic examination showed no inflammation in the anterior segment of both eyes; posterior segment evaluation by indirect ophthalmoscopy suggested retinal degeneration. One postmortem evaluation local spongy vacuolization was in several regions of the brain and the optical nerves had severe axonal degeneration.

Consistency of side choice in the milking parlour by holstein-friesian cows and its relationship with their reactivity and milk yield

Dairy cows often have to choose which of two sides to enter in the milking parlour. Some cows are very consistent in this choicė, and it is common to assume that when these cows are more disturbed are being milked in their non-preferred side. Such disturbance might involve significantly poor welfare. In order to assess this assumption, we decided to study the behaviour and milk yield of dairy cows and their relationships with side preference in the milking parlour. The study was carried out at Cambridge University Farm, in a two-sided tandem milking parlour. The data collection followed the daily management routine. We recorded the side chosen by each cow (left or right) during 40 milking sessions. Data from 70 cows, which were present in at least 25 milking sessions (mode = 36), were included in the statistical analysis. Cows' reactivity (CR) during premilking udder preparation, time spent fitting the milking cluster (FT), milk yield (MY) and duration of milking (DM) were measured. There was evident individual variation in the consistency of side choice. Individual differences (ANOVA, P < 0.001) were also found in CR, FT, MY and DM; although these variables were not significantly affected by the side or the interaction animal × side (ANOVA, P < 0.05). The comparison between left and right side means (paired t-test) of these variables did not show significant differences (P < 0.05). We concluded that there is no evidence that the cows were discomforted or stressed when milked in the non-preferred side of the milking parlour. © 2001 Elsevier Science B.V.

Factors affecting somatic cell counts and their relations with milk and milk constituent yield in buffaloes

Data concerning daily milk yield (MY), percentage of milk fat (%F), protein (%P), lactose (%LT), and total solids (%TS), and somatic cell counts (SCC) for a herd of 222 Murrah buffalo reared in the state of São Paulo, Brazil, were collected monthly from 1997 to 2000 in order to study the factors affecting SCC and their relation to milk production and constituents during lactation. SCC decreased in the second month of lactation and increased thereafter, up to the ninth month of lactation. The interaction of month of lactation x order of calving was significant. Mean MY observed during the first month of lactation was 6.87 kg, which increased to 7.65 kg during the second month, and then decreased until the ninth month of lactation (3.83 kg). During the different months of lactation, %F, %P, %LT, and %TS ranged from 6.28 to 8.38%, 4.05 to 4.59%, 4.96 to 5.34%, and 16.94 to 18.55%, respectively. Calving year, calving order, and order of month of lactation significantly affected MY, %F, %P, %LT, and %TS. The regression coefficients of transformed SCC on MY and %LT were negative and significant during all months of lactation, showing that milk and lactose yield decreased with increased transformed SCC, causing losses to buffalo milk producers.

Variance heterogeneity for milk yield in Brazilian and Colombian Holstein herds

Heterogeneity of variances for milk yield (MY) was determined for Brazilian and Colombian herds. The herds were grouped as high or low variability within each country, using as criterion the phenotypic standard deviation (PSD) of MY in the contemporary groups of cows, from the first to the sixth calving. Brazilian and Colombian herds with PSD greater than 1,168 kg or 1,012 kg, respectively, were classified as high variability while the herd groups with values lower than those were classified as low variability. The genetic parameters for MY within each herd group were estimated using bivariate analysis in an animal model and the restricted maximum likelihood method with a derivative free algorithm, using 72,280 first lactations of cows, daughters of 1,880 sires. Heterogeneous variances were found, and Brazilian herds with high PSD had the greatest additive and residual genetic variances and heritability coefficients for MY. MY genetic correlation coefficients between herds of high and low variability within each country were 0.96 and 0.93 while between countries they varied from 0.72 to 0.81, suggesting that there was a reclassification of animals in the two countries and also heterogeneity of variances. This phenomenon leads to the questioning of the strategy of imported semen usage and the need to do genetic evaluations to identify sires with greater genetic potential for (sub) tropical environmental conditions.

Factors that cause genotype by environment interaction and use of a multiple-trait herd-cluster model for milk yield of Holstein cattle from Brazil and Colombia

Descriptive herd variables (DVHE) were used to explain genotype by environment interactions (G x E) for milk yield (MY) in Brazilian and Colombian production environments and to develop a herd-cluster model to estimate covariance components and genetic parameters for each herd environment group. Data consisted of 180,522 lactation records of 94,558 Holstein cows from 937 Brazilian and 400 Colombian herds. Herds in both countries were jointly grouped in thirds according to 8 DVHE: production level, phenotypic variability, age at first calving, calving interval, percentage of imported semen, lactation length, and herd size. For each DVHE, REML bivariate animal model analyses were used to estimate genetic correlations for MY between upper and lower thirds of the data. Based on estimates of genetic correlations, weights were assigned to each DVHE to group herds in a cluster analysis using the FASTCLUS procedure in SAS. Three clusters were defined, and genetic and residual variance components were heterogeneous among herd clusters. Estimates of heritability in clusters 1 and 3 were 0.28 and 0.29, respectively, but the estimate was larger (0.39) in Cluster 2. The genetic correlations of MY from different clusters ranged from 0.89 to 0.97. The herd-cluster model based on DVHE properly takes into account G x E by grouping similar environments accordingly and seems to be an alternative to simply considering country borders to distinguish between environments.

Pheno and genotyping of Staphylococcus aureus, isolated from bovine milk samples from São Paulo State, Brazil

In the present study, 87 Staphylococcus aureus isolates obtained from milk samples of 87 cows with mastitis in 6 different municipal districts of 2 regions of São Paulo State, Brazil, were compared pheno and genotypically. Pulsed-field gel electrophoresis (PFGE) analysis of the strains was performed, and PCR was carried out to detect genes for a number of staphylococcal cell surface proteins, exoproteins, and 3 classes of agr genes. Nine distinct S. aureus lineages (LA-LI) were identified by PFGE. The lineages LA and LE, which accounted together for 63 strains (72.2%), were prevalent and had been collected from all of the 6 municipal districts, indicating a broad geographic distribution of these lineages; LB, LC, LD, LF, LG, LH, and LI, however, were isolated sporadically and accounted for 24 strains (27.8%). Some characteristics, like penicillin resistance and the presence of cap8 and agr class II genes, were associated with the prevalent lineages (LA and LE), and penicillin susceptibility and the presence of cna and cap5 genes were associated with sporadic lineages. According to the present results, some S. aureus lineages possess a combination of genes that confer the propensity to cause and disseminate infection, and only a limited number of clones are responsible for the cases of bovine mastitis on the various farms. © 2004 NRC Canada.

Grazing time and milk production of crossbred cows in a rotational area of Elephant grass and Tanzania grass

This study was carried out in January of two consecutive years. The objective was to evaluate the grazing time, the grazing rate and the milk production of crossbred cows, managed in two rotational grazing areas, one with elephant grass (Pennisetum purpureum Schum. cv. Guaçu) and another one with Tanzania grass (Panicum maximum Jacq. cv. Tanzania), both with natural shade in the rest area. The experiment was divided in two phases, the first with 12 cows that remained day and night in the paddock and were milked twice a day. In the second phase 15 cows were observed and remained 10.43 hours in the paddock during the day, and were kept in a corral during the night. Each cow was observed every 15 minutes. Grass specie had no effect on milk production in the two phases of the experiment. The grazing time was 564 and 474 minutes and the grazing rate was 28.7 and 24.4 minutes/hour for the Elephant grass and Tanzania grass, respectively, in first phase. In the second phase,the grazing time was 461 and 426 minutes and the grazing rate was 42.7 and 39.4 minutes/hour for the Elephant grass and Tanzania grass, respectively. Correlations were observed (P<0.01) between grazing rate and the minimum temperature (-0.68), the maximum temperature (-0.76), the relative humidity (0.44) and the THI (-0.76).

Biological control of sheep parasite nematodes by nematode-trapping fungi: In vitro activity and after passage through the gastrointestinal tract

The main method used for the control of gastrointestinal nematodes in sheep production is the application of chemotherapeutic agents, which often lead to the selection of parasites resistant to given active principles. Biological control can be considered a promising alternative, contributing to an increase in the efficacy of verminous control. We determined the in vitro activity and in situ survival of the predatory fungi Arthrobotrys musiformis and Arthrobotrys conoides during passage through the gastrointestinal tract of sheep after oral administration of conidia in microencapsulated form and as a liquid in natura. Initial in vitro tests showed that both fungi were efficient in the predation of trichostrongylid L3 larvae present in the faeces of sheep naturally infected with gastrointestinal nematodes. The fungi presented high nematophagous activity, which was 99.3% for A. conoides and 73.7% for A. musiformis. A. conoides did not survive passage through the gastrointestinal tract under the conditions of the present experiment. On the other hand, A. musiformis was reisolated after administration in either microencapsulated or liquid form, suggesting that this species is a promising alternative for the control of nematodes in sheep since it survives without any protection (in natura). © Springer 2005.

The influence of sardine consumption on the omega-3 fatty acid content of mature human milk

Objectives: The purpose of this study was to investigate what effect the ingestion of sardines, rich in omega-3 series polyunsaturated fatty acids, has on the composition of breastmilk. Methods: This was a prospective study of 31 nursing mothers under observation at the Hospital Guilherme Álvaro. Each was given 2 kg of fresh sardines twice with a 15-day interval. Milk was sampled and a 24-hour dietary recall questionnaire was applied on days 0, 15 and 30. Milk was assayed for fatty acid content by gas chromatography. Statistical analysis of the results was performed using nonparametric tests with significance set at p < 0.05. Results: The results demonstrate that the nutritional intake of the nursing mothers was adequate at all three sample points. With regard to the omega-3 series fatty acid content of the breastmilk, it was observed that regular consumption and shorter intervals between ingestion and milk collection resulted in higher concentrations of docosapentaenoic acid and docosahexaenoic acid at 15 and 30 days into the study. Fatty acids from the omega-3 and omega-6 series exhibited a significant correlation, r 2 was 0.58 and 0.59 at 15 and 30 days, respectively. Conclusion: These results suggest that incorporating fish into the diets of nursing mother during lactation, in the form of 100 g of sardines two or three times a week, contributes to an increase in omega-3 series fatty acids. Copyright © 2006 by Sociedade Brasileira de Pediatria.

Efficacy of homeopathic treatment against natural infection of sheep by gastrointestinal nematodes.

The efficacy of the homeopathic treatment with the Fator Vermes, administered according to the manufacturer's recommendations, was evaluated against gastrointestinal nematodes infections in sheep. The experiment was divided into two phases: in the first phase (January/06/2004 to April/30/2004), the animals of the treated (n=10) and control (n=10) groups were treated individually with conventional anthelmintics to avoid deaths. In the second phase (April/30/2004 to July/06/2004), the sheep from the group that received the Fator Vermes were treated as they had been in the previous phase, while the control group animals were treated with conventional anthelmintics at 14 day intervals. In the first phase of the experiment, there was no significant difference (P>0.05) between group means regarding egg counts in feces (EPG), weight gain, or packed cell volume (PCV). Meanwhile, in the second phase, the control group sheep had a significantly higher weight gain, higher PCV values, and lower EPG counts. Infective larvae of Haemonchus spp., Trichostrongylus spp., Cooperia spp., and Oesophagostomum spp. were identified in the fecal cultures. After six months of daily treatment with the Fator Vermes, it was not possible to substantiate the product's benefits in both sheep health and productivity or in the prophylaxis of gastrointestinal nematode infections.

Analysis of fluoride concentration in mother's milk substitutes

The aim of the present study was to determine the fluoride concentration in some brands of mother's milk substitutes and evaluate the possibility of developing dental fluorosis by consuming these products. The products, all powdered, were divided into 3 groups: infant formulae (group I, n = 7), milk-based (group M, n = 8) and soy-based (group 8, n = 3). Samples from 3 cans of different batches of each brand were reconstituted in deionized water and analyzed using the specific electrode method, after hexamethyldisiloxane (HMDS) facilitated diffusion. The fluoride content (mg F/L) of the products ranged from 0.044 to 0.326 (I), 0.014 to 0.045 (M) and 0.253 to 0.702 (S). There was significant difference in the fluoride content of cans from distinct batches (p < 0.05) in most of the brands. The reconstitution of all products in water with optimal fluoride concentration for consumption during the mineralization phase of the primary teeth could result in daily fluoride intake above 0.07 mg F/kg body weight/day. Therefore, the consumption of these products, especially when reconstituted with optimally fluoridated water, could increase the risk of developing dental fluorosis.

Simultaneous effects of total solids content, milk base, heat treatment temperature and sample temperature on the rheological properties of plain stirred yogurt

Response surface methodology was used to establish a relationship between total solids content, milk base, heat treatment temperature, and sample temperature, and consistency index, flow behaviour index, and apparent viscosity of plain stirred yogurts. Statistical treatments resulted in developments of mathematical models. All samples presented shear thinning fluid behaviour. The increase of the content of total solids (9.3-22.7 %) and milk base heat treatment temperature (81.6-98.4°C) resulted in a significant increase in consistency index and a decrease in flow behaviour index. Increase in the sample temperature (1.6-18.4°C) caused a decrease in consistency index and increase in flow behaviour index. Apparent viscosity was directly related to the content of total solids. Rheological properties of yogurt were highly dependent on the content of total solids in milk.

Evaluation of Ir-based modifiers in the simultaneous determination of As, Bi, Pb, Sb, and Se in milk by graphite furnace atomic absorption spectrometry

Different modifiers (IrCl3, W+IrCl3, Zr+IrCl 3) and coatings (Ir, W-Ir, Zr-Ir) were evaluated for the simultaneous determination of arsenic, bismuth, lead, antimony, and selenium in milk by graphite furnace atomic absorption spectrometry using the 'end-capped' transversely heated graphite atomizer (THGA). Integrated platform, pretreated with Zr-Ir as permanent modifier, was elected as the optimum surface modification resulting in up to 250 firings. Two additional recoatings were possible without significant changes in the analytical performance (750 firings). For 20 μL of matrix-matched standard solutions using diluted (1:10) milk samples, typical correlation coefficients between integrated absorbance and analyte concentration (5.00-20.0 μg/L) was always better than 0.999. The levels of the analytes found in commercial milk samples were lower than the limit of detection: 2.9 μg/L As, 2.9 μg/L Bi, 1.8 μg/L Pb, 1.9 μg/L Sb, and 2.5 μg/L Se. Recoveries were found within the following intervals: 88-114% for As, 89-118% for Bi, 89-113% for Pb, 91-115% for Sb, and 92-115% for Se. The relative standard deviations (n = 12) were ≤2% (As), ≤ 5% (Bi), ≤ 1.4% (Pb), ≤ 3% (Sb), and 5% (Se), and the respective calculated characteristic masses were 54 pg As, 55 pg Bi, 40 pg Pb, 56 pg Sb, and 51 pg Se.

Effect of milk treatment on acidification, physicochemical characteristics, and probiotic cell counts in low fat yogurt

The effect of milk treatment (heat, high hydrostatic pressure - HHP, or combined heat and HHP) on acidification, physicochemical characteristics, and probiotic cell counts in low fat yogurt was studied. All samples were analyzed for fermentation time, pH, titratable acidity, total solids, water-holding capacity, syneresis, Hunter L*, a*, and b* values, Streptococcus thermophilus, Lactobacillus delbrueckii ssp bulgaricus, L. acidophilus, and Bifidobacterium longum. The application of HHP combined with thermal treatment resulted in yogurt gels with attractive physicochemical characteristics and high water-holding capacity. In addition to this, the milk treatment did not affect the probiotic bacteria growth. The balance of strains in the starter culture and level of inoculation influenced the yogurt fermentation and properties. The use of combined heat and HHP to treat milk before yogurt fermentation could be an alternative process for obtaining high quality, additive-free healthy products.

Sheep and cattle grazing alternately: Nematode parasitism and pasture decontamination

Three grazing management systems were compared to examine pasture decontamination of gastrointestinal nematode parasites (GIN) of sheep (Ovies aries) and cattle (Bos taurus). They consisted of sheep and cattle grazing paddocks alternately for 32, 96 or 192 days over 2 years. Pastureland (8.43 ha) was subdivided into six areas of eight paddocks each to produce an eight-paddock rotational grazing system. Every paddock was grazed for 4 days and then rested for 28 days. Sixty-six Ile de France ewes and 12 steers were randomly divided into three groups (22 sheep and four cattle per group). Each grazing system included a cattle area and a sheep area. Sheep and cattle interchanged areas every 32 days in system 1 (Group 1), every 96 days in system 2 (Group 2) and every 192 days in system 3 (Group 3). Fecal examination and larvae counting on pasture were performed every 32 days. During summer, winter and spring 2005, tracer lambs free of nematode infection were introduced into each sheep group and later sacrificed for quantification and identification of GIN species. All cattle were sacrificed for the same purpose. The main parasites found in tracer lambs were Haemonchus contortus and Trichostrongylus colubriformis, and in cattle, Haemonchus similis, Cooperia punctata and Oesophagostomum radiatum. Pasture contamination by sheep-infective GIN larvae was considerably reduced after 96 or 192 days of cattle grazing. Cross-infections between sheep and cattle GIN were not significant, which suggested that integrated grazing using such animals could be used for pasture decontamination. However, as effective anthelmintics were not available, decontamination was not sufficient for proper prophylaxis of GIN infections in Ile de France sheep, which are quite susceptible to such parasites. © 2007 Elsevier B.V. All rights reserved.