Toxicity of Copper Sulfate to Flavobacterium psychrophilum and Rainbow Trout Eggs

Abstract

Tests were conducted to determine the concentrations of copper sulfate needed to kill Flavobacterium psychrophilum, the cause of bacterial coldwater disease, either in vitro or on Rainbow Trout Oncorhynchus mykiss eggs. For the in vitro test, a plastic strip dipped in a solution of F. psychrophilum was exposed for 15 min to copper sulfate solutions of 0, 1, 5, 10, 20, 35, 50, 75, or 100 mg/L. Bacteria were “too numerous to count” at concentrations ≤10 mg/L CuSO₄; significant reductions in prevalence relative to untreated controls were noted for concentrations ≥35 mg/L. However, CFUs were still observed at 50 and 75 mg/L (20% of plates with tryptone yeast extract salts media). No yellow-pigmented CFUs typical of F. psychrophilum were observed at 100 mg/L CuSO₄. For the in vivo test, eggs were exposed for 15 min to 100, 300, 500, and 700 mg/L CuSO₄ or 100 mg/L iodine (control). Survival to hatch was significantly lower at 500 (44.3 ± 15.2%, mean ± SD) or 700 mg/L CuSO₄ (1.7 ± 0.8%) than for controls treated with 100 mg/L iodine (93.6 ± 0.9%) or at copper sulfate concentrations ≤300 mg/L. The 15-min LD₅₀ and LD₁₀ for copper sulfate were 461 mg/L (95% confidence interval: 457–466 mg/L) and 259 mg/L (251–266 mg/L). The prevalence of yellow CFUs at 100 mg/L CuSO₄ (40.0%) was significantly higher than in untreated controls. Significant reductions in yellow CFUs were achieved using 300, 500, or 700 mg/L CuSO₄ (7.5, 2.5, or 0.0% of plates with CFUs, respectively) or 100 mg/L iodine (2.5%), relative to untreated control eggs. Overall, since the concentrations of copper sulfate required to eliminate F. psychrophilum were toxic to the eggs, copper sulfate is not recommended for coldwater disease control in Rainbow Trout eggs based on conditions and parameters in this study.

Received July 7, 2011; accepted March 17, 2013     

Effects of ionised or chelated water-soluble mineral mixture supplementation on growth performance,nutrient digestibility,blood characteristics,meat quality and intestinal microbiota in broilers

1. An experiment was conducted to study the effects of dietary supplementation of water-soluble ionised or chelated mineral mixture on growth performance, nutrient digestibility, blood characteristics, relative organ weight, meat quality and excreta microflora in broilers.

2. A total of 408 Arbor Acres broilers (17 birds in 8 replicate pens) were randomly allocated into one of the following three treatments: (1) Control/basal diet (CON), (2) T1 (basal diet + 0.5% ionised mineral mixture solution, pH 3.0) and (3) T2 (basal diet + 0.5% chelated mineral mixture solution, pH 3.0).

3. The body weight gain was greater and feed conversion ratio was lower in broilers supplemented with ionised or chelated mineral liquid complex compared to CON during the grower and overall phase of the experiment.

4. No significant effect in the concentration of Ca and P in the blood was observed in birds supplemented with ionised or chelated mineral mixture solution. No adverse effects were observed in organ weight and meat quality with ionised or chelated mineral mixture supplementation.

5. Regarding intestinal microbiota counts there was a reduction of Escherichia coli counts in the small intestine in ionised mineral supplemented birds. In the large intestine, E. coli as well as Salmonella populations were reduced in ionised mineral supplemented birds.

6. In conclusion, ionised or chelated minerals have partial positive effects in improving growth performance and reducing pathogenic bacteria load in the gastro-intestinal tract.

     

Ozone Disinfection of Eggs from Gilthead Seabream Sparus aurata,Sea Bass Dicentrarchus labrax,Red Porgy,and Common Dentex Dentex dentex

Abstract

The risk of fish pathogen transmission via eggs can be reduced by disinfection in ozonated seawater. The aim of this study was to determine the suitable conditions for ozone disinfection of the eggs of gilthead seabream Sparus aurata, sea bass Dicentrarchus labrax, red porgy Pagrus pagrus, and common dentex Dentex dentex. The eggs were disinfected with a concentration (C) of 0.5 mg of ozone/L of water at four different exposure times (T = 2, 4, 8, and 16 min). The hatching rate was determined in triplicate for each treatment. Bacterial colonies were counted on tryptic soy agar and thiosulfate–citrate–bile salts–sucrose agar. At the end of the experiment, bacterial load and hatching rate were assessed together to determine the optimal ozone treatment values, which were estimated in CT units (i.e., C [= 0.5 mg/L] × T [min]). Optimal values were CT 2–4 (T = 4–8 min; 18°C) for gilthead seabream and red porgy, CT 2 (T = 4 min; 18°C) for common dentex, and CT 4 (T = 8 min; 15°C) for sea bass.

Received April 12, 2011; accepted February 2, 2012     

Effect of starting body fat content and genotype of laying hens on the changes in their live weight,body fat content,egg production and egg composition during the first egg-laying period

1. A total 120 laying hens (60 TETRA BLANCA white egg layers and 60 TETRA SL brown egg layers) were selected from 250 TETRA BLANCA and 250 TETRA SL pullets based on their predicted body fat content by means of computed tomography (CT) at 16 weeks of age. Three groups of pullets were chosen for the investigation with the highest (n = 20), lowest (n = 20) and average (n = 20) body fat content.

2. Changes in the live weight, body fat content, egg production and egg composition of the chosen animals were recorded at 32, 52 and 72 weeks of age.

3. Based on the results, it was established that differences in starting body fat content of the hens remained the same during the experimental period. The differences between the two extreme groups were statistically significant at each age.

4. The starting body fat content of the hens affected the rate of egg production, i.e. hens with high starting body fat content produced 11–14 eggs fewer than the hens with a low or average body fat content but had no effect on the composition of the eggs.

5. Genotype affected almost all of the examined traits: TETRA BLANCA hens had lower live weight and higher body fat content during the experimental period and produced fewer eggs with lower albumen and higher yolk, dry matter and crude fat content than the TETRA SL hens.

     

Effective,appropriate and simple culture,egg hatching and cryopreserving of the nematode Cheilospirura hamulosa

1. Successful invasion by nematode parasites is associated with several factors including egg hatching at the right time in their hosts. To determine a simple and appropriate medium for culture and egg hatching of the highly pathogenic species of the Acuariidae family, Cheilospirura hamulosa were cultured in three different media. In addition the viability of C. hamulosa eggs was determined after storage in frozen infected gizzards.

2. Eggs removed from the uteri of the female worms in infected gizzards were pooled and washed in distilled water and screened under a stereo dissecting microscope. Eggs were counted and cultured in three different media, nutrient agar, normal saline 0.9% and Bearman, at room temperature. Additionally, 10 infected gizzards were kept at ?20°C for 2 and 8 months.

3. After 4–5 d there had been no growth in the nutrient agar medium, whereas 11% of the cultured eggs in the Bearman medium contained larvae 2–3 d after culturing. In 0.9% normal saline medium the two polar knobs appeared on the two poles of the eggs at 2 d post cultivation, and 74% of the eggs contained a larva on the third day. Mature larvae gradually exited from the eggs.

4. Eggs collected from female worms in gizzards frozen at ?20°C were cultured in the same three culture media at room temperature. Larvae were visible in the eggs after 2–3 d in the Bearman and 0.9% normal saline media and hatched thereafter.

5. The 0.9% normal saline medium is recommended for egg hatching and cultivation of C. hamulosa due for simplicity, efficacy and cost effectiveness. Moreover, freezing of the infected gizzards at ?20°C is proposed for long-term storage of the eggs.     

Lactobacillus species in drinking water had no main effects on sulphur compounds from manure,egg quality,and selected serum parameters of second cycle hens

ABSTRACT

1. The aim of this study was to investigate the effects of a combined probiotic product (Lactobacillus paracasei, L. plantarum, and L. rhamnosus) on egg quality, sulphur compounds in manure and serum biochemistry of second cycle hens.

2. A total of 48 White Leghorn hens, at 52- to 54 weeks of age, were treated in a completely randomised design with water containing 0 or 1.8375 × 10¹⁰ cfu/l of probiotics for 8 weeks.

3. Probiotic supplementation did not affect egg quality. Albumen height and Haugh units were in general lowest in week 2 and highest in week 6.

4. For manure and serum parameters, water with or without probiotics produced statistically similar effects. An interacting trend for increasing concentrations of methyl mercaptan in manure was noted for probiotics x week, and should be further investigated. The week of supplementation significantly affected hydrogen sulphide, dimethyl sulphide, and triglycerides.     

Influence of citrus flavonoids on laying hen performance,inflammatory immune response,egg quality and yolk oxidative stability

1. The objective of this study was to investigate the effects of dietary supplementation with natural flavonoids (naringin and hesperidin) on laying hens’ performance, cellular immunity and egg quality parameters.

2. A total of 72 individually caged laying hens were allocated into 1 of 6 treatment groups: a control (C) group that was fed with a basal diet and groups that were offered the same diet further supplemented with hesperidin at 0.75 g/kg (E1), or 1.5 g/kg (E2), or naringin at 0.75 g/kg (N1), or 1.5 g/kg (N2) or α-tocopheryl acetate at 0.2 mg/kg (VE) for 67 d.

3. Supplementation with naringin or hesperidin did not affect the performance and egg quality (P > 0.05) apart from an improvement in the yolk colour that was more orange in naringin and hesperidin groups in comparison to the controls (P-linear < 0.05). Egg yolk and plasma cholesterol levels were not affected by citrus flavonoids (P-linear > 0.05).

4. Inflammatory immune response, measured by phytohaemagglutinin skin test (PHA), was suppressed in laying hens that were fed with either naringin (P-linear < 0.05) or hesperidin (P < 0.05). Egg yolk oxidative stability was improved from the 4th d after naringin or hesperidin supplementation. This beneficial effect was comparable to that of α-tocopheryl acetate and was observed in eggs that were stored for up to 120 d.

5. In conclusion, naringin and hesperidin may favourably prolong the shelf life of eggs, appear to possess anti-inflammatory properties and could improve the yolk colour without any side effects on the performance or egg quality traits.     

The effects of phytase and root hydroalcoholic extract of Withania somnifera on productive performance and bone mineralisation of laying hens in the late phase of production

1. A 6-week study was conducted to investigate the effects of phytase and hydroalcoholic extract of Withania somnifera root (WS) on productive performance and bone mineralisation of laying hens in the late phase of production.

2. Diets were arranged factorially (3?×?2?×?2) and consisted of a positive control with adequate Ca (4·37%) and nonphytate P (NPP; 0·39%) and a negative control diet with Ca (4·06%) and NPP (0·36 %); three concentrations of Withania somnifera (0, 65 and 130?mg/kg diet); and two concentrations of microbial phytase (0 and 300 U/kg diet).

3. A total of 144 72-week-old Hy-Line W36 laying hens were randomly assigned to the 12 treatment groups. Each treatment was replicated 4 times (4 x 3 hens). Egg production and egg weight were recorded daily, while feed intake and egg quality traits were recorded every two weeks. Bone quality traits were evaluated at the end of experiment.

4. Withania somnifera supplementation increased egg production and lowered egg weight only in the second two weeks of the experiment. Addition of phytase significantly depressed specific gravity of the eggs for the entire experiment period. No dietary treatment effects were observed on egg shell thickness and yolk weight.

5. Withania somnifera at 130?mg/kg did not affect feed intake. The hens fed on the positive control diet had higher albumen weight than the negative control diet in the second two-week period. Supplementation of the positive control diet with 65?mg/kg Withania somnifera in the absence of phytase significantly improved shell weight compared with the negative control (5·779 vs. 5·273?g respectively).

6. Supplementing Withania somnifera significantly improved Ca and P retention in tibia bone. In addition, an increase in tibia bone P was observed with phytase supplementation. There were significant interactions between Withania somnifera content and phytase for tibia bone Ca and P.

7. The results of this experiment indicated that dietary Withania somnifera has beneficial effects on tibia bone Ca and P content, and phytase improved tibia bone P retention without adverse effects on productive performance.     

Studies on occurrence,characterisation and decontamination of emerging pathogenic Escherichia coli (STEC,ETEC and EIEC) in table eggs

1. Escherichia coli is one of the most common facultative anaerobic species present in the gastrointestinal tract of animals and human beings. Usually they occur as commensals, but some serotypes can cause significant illnesses in humans as well as mammals and birds.

2. The occurrence of E. coli in different categories of table eggs collected from markets was evaluated. Isolates were analysed for the presence of virulence genes, antibiotic susceptibility pattern and efficacy of peracetic acid and chlorine for the purpose of decontaminating table eggs.

3. Significant differences were observed in the occurrence of E. coli between different groups viz. processed (cleaned, washed, sanitised and packed eggs), unprocessed (un-cleaned, un-sanitised and loose eggs) and free range (eggs obtained from backyard poultry) table eggs. Overall, E. coli occurred in table eggs at 28.6% with 22.9, 29.2 and 50.0% occurrence in processed, unprocessed and free-range table eggs, respectively.

4. A total of 24 isolates of E. coli were obtained and screened for virulence genes viz. STH, SLT1/2 and INVE genes. Of the 24 isolates recovered, 10 typeable isolates belonged to O141, O119, O9, O120 and O101 serotypes, while the remaining 14 were untypeable. Antibiograms of the isolates showed multiple antimicrobial resistance (MAR) index in the range of 0.13–0.40.

5. Peracetic acid (PAA) and chlorine (CL) were studied for their sanitisation efficacy; concentrations of 100 mg/kg of PAA and 200 mg/kg of CL completely inactivated E. coli over the egg surface and also resulted in 2.58 and 2.38 log reduction in total viable counts (TVC), respectively.

6. The presence of virulence-associated shiga-like toxin (SLT1/2) and invasion E (INVE) genes and antimicrobial resistance among the emerging serotypes of pathogenic E. coli isolated from table eggs has public health implications. It underscores the need to implement better management practices across the production systems and marketing channels to produce E. coli-free wholesome eggs for consumers.     

Association of ADSL gene polymorphisms with meat quality and carcass traits in domestic pigeons (Columba livia)

ABSTRACT

1. Adenylosuccinate lyase (ADSL) plays an important role in the synthesis of inosine monophosphate (IMP). In this trial, a total of 200 pigeons were sampled and slaughtered. Seven meat quality traits and 11 carcass traits were measured. DNA sequencing was used to detect nucleotide mutations, and associations between ADSL gene polymorphisms and meat quality and carcass traits were analysed.

2. Sequencing results showed that 9 nucleotide mutations were found in the exons of the ADSL gene. All the mutations were synonymous except C13065G, which caused a change in amino acids (Ser to Arg). In addition, two of the detected single nucleotide polymorphisms (SNPs) had significant associations with meat quality and carcass traits.

3. For the C13065G SNP located in exon11, the IMP content of breast muscle in AA and AB genotype was higher than in the BB genotype (P < 0.01). The SNP G10696A located in exon10 was significantly associated with carcass rate, in which AA and AB genotype were higher than the BB genotype (P < 0.01).

4. The results indicated that the ADSL gene has a close association with meat quality and carcass traits in domestic pigeons, and G10696A and C13065G SNPs could be applied as genetic markers in molecular marker-assisted breeding of pigeons.     

Early and 24 h post-mortem changes in breast muscle quality traits of two turkey genotypes and their reciprocal crosses raised under semi-confined conditions

1. An experiment was conducted to determine the effect of reciprocal crossing of turkeys on early and 24 h post-mortem changes in quality traits of their breast muscles.

2. The turkeys of slow-growing (SG) and fast-growing (FG) lines as well as SF (SG × FG) and FS crosses (FG × SG) were reared with access to free range.

3. After slaughter turkey breast muscles were examined in the following terms: 5 min, 45 min, 2 h and 24 h post-mortem, for: temperature, pH, glycogen content (G), lactate content (L) and electrical conductivity (EC). Quality attributes of the breast meat were evaluated based on chemical composition, water holding capacity (WHC), cooking loss (%), shear force (N) and colour (L*, a*, b*).

4. Despite differences in the rate of post-mortem changes, the genotype of turkeys had no significant effect upon many quality traits assessed 24 h post-mortem. Meat of lighter birds (SG and SF) was characterised by a lower fat content but a similar protein content compared to meat of FS and FG turkeys. In addition, meat of males from these groups was darker. Meat from the breast muscles of heavier birds (FS and FG) was harder.

5. Significant negative maternal effects were determined for temperature of meat of both male and female turkeys, for pH₂ and EC₂₄ of males as well as for L₂, L₂₄ and cooking loss of female meat. Positive heterosis was confirmed only for pH₂ of female meat and for G₂ of male meat.

6. In summary, the direction of fast- and slow-growing turkey crossing may affect the quality of their meat. However, meat of both types of hybrids reared under semi-confined conditions (with the possibility of using free range) was characterised by appropriate quality parameters.

     

Organic management of dietary rosemary extract in dairy sheep: effects on milk quality and clotting properties

The increasing demand for animals from organic breeding systems has increased interest in certain natural substances, called nutraceuticals, to stimulate the organic defenses of the animals. The aim of this trial was to study the effects of dietary rosemary extract in 36 ewes, from 57 to 154 days of lactation, divided into three groups: CTR (basal diet), ROXLD (600 mg extract/head/day) and ROXHD (1,200 mg extract/head/day). A significantly higher quantity of milk and quantitative daily production of protein, casein, fat, and lactose were observed in the milk of animals in the ROXHD group compared with milk from animals in the CTR and ROXLD groups. No significant differences were observed for somatic cell counts, considering that treated groups showed lower values compared with controls. A significant decrease in clotting time (r) and increase in curd firmness (a ₃₀ ) were observed in milk of both treated groups (ROXLD and ROXHD) compared with the CTR group. These results could be related to the significantly higher acidity values, pH and SH°, observed in the milk of animals from the treated groups. Dietary rosemary extract in dairy sheep enhanced milk yield, quality, and renneting properties due to its “natural, functional ingredients.”

     

Changes in egg quality traits during the last phase of production: is there potential for an extended laying cycle?

1. A field study was conducted to investigate the deterioration of eggshell quality at the end of lay and examine the potential to extend the production cycle. A total of 1200 eggs were assessed originating from commercial farms in Belgium: eggs were random sampled at the collection belt at 57–65 weeks of age and at the end of the production cycle (74–92 weeks).

2. Based on a linear mixed model, egg quality was estimated for an average flock at 60 weeks of age and changes in quality traits were predicted until the end of the laying cycle.

3. Egg weight increased by 0.07 g every week from 60 weeks of age onwards and shape index decreased by 0.04 unit weekly (P < 0.001). Haugh unit values decreased weekly by 0.38 units whereas relative yolk weight was unaffected after 60 weeks of age. Relative albumen weight showed a weekly increase of 0.02% and relative shell decreased by 0.02% weekly until the end of lay.

4. Shell quality traits were also influenced by age: shell index decreased by 0.013 g weekly, shell thickness was calculated to be 0.23 µm thinner every week, deformation increased by 0.06 µm weekly from 60 weeks to the end of the laying cycle. Variability of the deformation of eggs indicated more heterogeneous shell quality at the end of the production cycle. Dynamic stiffness increased from 60 weeks of age on.

5. Laying hens were depopulated on average at 80 weeks of age (varying from 74–92 weeks). Although ageing had a significant effect on most of the egg quality traits, egg quality was still acceptable at the end of lay, indicating the potential to extend the laying cycle.     

Survey on the microbiological quality of Chinese food preparations

The microbiological quality of 118 samples of traditional Chinese food from restaurants and take-away establishments in the provinces of Padua, Treviso, and Venice was examined (April–July, 2008). These food items included various ready-to-eat products. The microbiological quality of the majority of these food items was acceptable; only 12% of samples had values greater than or equal to 6 log CFU/g (eight items were salads) and 19% of samples had values greater than 500 CFU fecal coliforms/g (p < 0.01 to 0.001). The Aw lower values were in sauces (0.839), but were greater than 0.95 in other food sources. No pathogens, such as Salmonella spp. or Listeria monocytogenes, were detected, but Bacillus cereus and coagulase-positive Staphylococcus were both identified. Thus, although final heating reduces the levels of microorganisms present in foods, it does not inactivate any toxins produced by such organisms.

     

Effects of avgard™ treatment on the microbiological flora of poultry carcases

1. The efficiency of the AvGard? (or Assur‐Rince? in the USA) trisodium phosphate poultry carcase decontamination process was evaluated during both manual and industrial trials against total aerobic mesophilic count (TAMC), thermotolerant coliforms, Pseudomonas, Enterobacteriaceae, Campylobacter, Listeria monocytogenes and Salmonella.

2. The TSP treatment proved to have significant effects on the bacterial decontamination of poultry neck skin, lowering the contamination by a factor of about 10 for TAMC and of 100 for Coliform and Pseudomonas.

3. Numeration of Salmonella with an innovative miniaturised most probable number method has proved that the effect upon these micro‐organisms was also close to 2 log₁₀ reduction.

4. The effect of TSP treatment on the ecological balance of psychrotrophic bacterial flora was also investigated to study the origin of the shelf‐life flora of treated carcases (Pseudomonas being reduced to the limit of detection) and to ascertain whether L. monocytogenes might gain a competitive advantage. In fact AvGard? reduced the number of L. monocytogenes on poultry carcases.

5. As a consequence of the virtual elimination of the Pseudomonas usually present, Brochothrix thermosphacta became the main species responsible for putrefaction.

6. Because the growth rate of Brochothrix thermosphacta was greater than that of L. monocytogenes at refrigeration temperature, it was considered that putrefaction would occur before the emergence of large numbers of L. monocytogenes.     

Relationship between egg‐shell colour and two measurements of shell strength in the Vasca breed

1. Egg‐shell colour, egg specific gravity, shell thickness and egg weight were determined for 2080 eggs from three varieties of the Vasca, a Spanish brown‐egg‐laying hen.

2. Intermediate, positive and significant (P < 0·01) correlation coefficients were found between egg‐shell colour and specific gravity (0·25), or shell thickness (0·21). There was a very high (0·84), significant (P < 0·01) correlation between the measures of shell strength.

3. Shell thickness was accurately predicted with both specific gravity and egg weight as independent variables (determination coefficient 0·74); eggshell colour did not explain any further variation.

4. All traits showed considerable departure from normality in the form of negative kurtosis (shell colour and specific gravity), positive kurtosis (shell thickness and egg weight), negative skewness (shell thickness) or positive skewness (egg weight).

5. Egg‐shell colour, specific gravity and shell thickness were less in July, in old birds and in eggs laid in the morning. Differences in egg quality traits between the three varieties were not significant.

     

Effects of main cereal type and feed form on production performance,egg quality and egg sanitary indices of laying hens

ABSTRACT

1. The experiment was conducted to evaluate the effects of cereal types (maize or wheat) and feed forms (pelleted or mash feed) on production performance, egg quality and egg sanitary indices in laying hens.

2. Three hundred and sixty hens (Jinghong No. 1) at 18 weeks of age were randomly assigned to four treatments with six replicates of 15 hens per replicate according to a 2 × 2 factorial design with two cereal types (maize or wheat) and two feed forms (pelleted or mash feed).

3. Compared with the wheat-based diet, the maize-based diet improved (P < 0.05) average egg weight of laying hens. Yolk colour of hens fed with the maize-based diet was higher (P < 0.05) in comparison to those fed the wheat-based diet, while Haugh units were lower (P < 0.05) for the maize-based treatment. Egg mass and average daily feed intake of hens fed the pelleted diet were higher (P < 0.05) than of those fed the mash diet. However, the mash diet improved (P < 0.05) yolk colour compared with the pelleted diet. The percentage of dirty eggs for the wheat-based diet was higher (P < 0.05) than for the maize-based diet. The percentage of dirty eggs was higher (P < 0.05) in birds fed the pelleted diet compared with those fed the mash diet. There were interactions (P < 0.05) between cereal type and feed form, with regard to average egg weight and shell thickness.

4. In conclusion, dietary cereal type affected average egg weight, yolk colour and Haugh units in eggs, while feed form influenced egg mass, average daily feed intake and yolk colour.     

Pharmacokinetics of tapentadol in laying hens and its residues in eggs after multiple oral dose administration

1. The aim of the study was to evaluate the pharmacokinetics (PKs) of tapentadol (TAP), a novel opioid analgesic, in laying hens after intravenous (IV) and oral (PO) administration and to quantify the concentrations of TAP residues in eggs.

2. Twenty healthy laying hens were divided into three groups: A (n = 6), B (n = 6) and C (n = 8). The study was conducted in two phases. Groups A and B received TAP by IV and PO routes at the dose of 1 and 5 mg/kg, respectively.

3. No visible adverse effects were observed after administration of the drug. TAP plasma concentrations were detectable up to 4 h following administration. Following IV administration, TAP plasma concentrations were only higher than the minimal effective concentration (148 ng/ml) reported for humans for 1 h. After single PO administration, plasma concentrations of TAP would not conform to software algorithms and the PK parameters were not calculated. TAP concentration following multiple PO doses at 5 mg/kg for 5 d was found to be higher and more persistent (12 h vs. 7 h) in yolk compared with albumen.

4. This is the first PK study on the novel atypical opioid TAP in laying hens. Further studies are required to investigate the analgesic efficacy and actual effective plasma concentration of TAP in this species.     

Body development, carcass, and meat quality of confined lambs fed increasing levels of whole rice meal

The objective of this trial was to evaluate the effect of whole rice meal (WRM) inclusion in the concentrate upon body development, carcass traits, and meat quality of lambs. Twenty-four castrated lambs with an average initial body weight of 17.90?±?2.72 kg were randomly blocked according to two genetic groups (Corriedale and Texel by Corriedale crossbreds). Three isocaloric (11.3 MJ/kg of metabolizable energy) and isonitrogenous (17 % crude protein) diets were offered to the animals for 74 days. Diets consisted of 40 % forage and 60 % concentrate diet, on a dry matter basis, with 0, 15, or 30 % of WRM inclusion into the concentrate. Body growth (after slaughter), carcass, and meat traits were evaluated on each animal. Results obtained indicated that genotype did not affect body growth, carcass, and meat traits except for yellowness. No significant interaction between diet and genotype were detected. Inclusion of up to 30 % WRM did not significantly (P?>?0.05) affect body growth, carcass, and meat traits, except for meat color. Meat luminosity progressively increased (36.32?+?0.055X) while redness (15.13???0.03X) decreased with the inclusion of WRM in the diet, but still remained within acceptable values. The study indicates that WRM may be included up to 30 % in the concentrate replacing corn without adverse effects upon body development, carcass traits, and meat quality of lambs.     

The Effect of Anthelmintic Capsules on the Egg Output and Larval Viability of Drug-resistant Parasites

Challenge with an equal mix of drug-resistant and drug-susceptible larvae of Teladorsagia circumcincta resulted in infections in groups of lambs (n = 6) either untreated or given controlled-release capsules, containing either albendazole or ivermectin. Lambs treated with albendazole capsules contained similar numbers of adult worms at necropsy to the other groups but had no detectable faecal egg count. Animals treated with ivermectin capsules had similar worm burdens and faecal egg counts to the control group but the worms had significantly higher numbers of eggs in utero. These results provide evidence for suppression of egg production by both anthelmintic treatments. The observation that albendazole caused a significant reduction in the developmental success of parasite eggs also has implications for the use of faecal egg count as an indicator for pasture contamination with resistant parasites. In two further groups of lambs, either untreated or given albendazole capsules, treatment caused a significant reduction in egg count and adult worm burden of Trichostrongylus colubriformis. No significant effects were observed on in utero egg counts or egg viability and the apparent effect on the number of eggs produced in faeces per adult female was not significant (p = 0.077). There was, therefore, no evidence that albendazole controlled-release capsules caused suppression of egg output in this species.