The effect of vibration therapy on neck myofascial trigger points: A randomized controlled pilot study.

BACKGROUND: The purpose of this study was to evaluate the effect of low-frequency self-administered vibration therapy into myofascial trigger points in the upper trapezius and levator scapulae on patients with chronic non-specific neck pain. METHODS: Twenty-eight patients with chronic non-specific neck pain were randomly assigned into a vibration group, receiving 10 self-applied sessions of vibration therapy in the upper trapezius and levator scapulae trigger points; or a control group, receiving no intervention. Self-reported neck pain and disability (Neck Disability Index) and pressure pain threshold were assessed at baseline and after the first, fifth and 10th treatment sessions. FINDINGS: Significant differences were found in the vibration group when compared to the control group after the treatment period: the vibration group reached lower Neck Disability Index scores (F = 4.74, P = .033, η2 = 0.07) and greater pressure pain threshold values (F = 7.56, P = .01, η2 = 0.10) than the control group. The vibration group reported a significant reduction in Neck Disability Index scores (χ2 = 19,35, P = .00, Kendall's W = 0.28) and an increase in pressure pain threshold (χ2 = 87,10, P = .00, Kendall's W = 0.73) between the assessment times over the course of the treatment. The mean increase in pressure pain threshold in the vibration group after the 10 sessions was 8.54 N/cm2, while the mean reduction in Neck Disability Index scores was 4.53 points. INTERPRETATION: Vibration therapy may be an effective intervention for reducing self-reported neck pain and disability and pressure pain sensitivity in patients with chronic non-specific neck pain. This tool could be recommended for people with non-specific neck pain.

A probabilistic Poisson-based model to detect PRRSV recirculation using sow production records.

Porcine reproductive and respiratory syndrome (PRRS) is a viral disease associated with a decrease in the number of born alive piglets (NBA) and an increase in the number of lost piglets (NLP) per farrowing. Under practical conditions, it is critical to assess whether a farm is suffering PRRSV recirculation in the sow herd as soon as possible. The aim of this research work was to develop a new method to detect potential PRRSV recirculation in sow production farms. Sow reproductive performance records from one farm (farm T) were used to set up the method and records from ten additional farms (farms V1 to V10) were used for validation. A conditional Poisson model of NLP on NBA was proposed to fit the data. A three-step procedure was implemented to detect potential PRRSV recirculation: (i) computation of the maximum-likelihood estimates of the expected values of NBA and NLP in a PRRSV non-recirculating scenario; (ii) calculation, for each farrowing, of the p-value associated with the probability of jointly observing deviations towards decreased NBA and increased NLP. The detection of a potential PRRSV recirculation was based on (iii) the combined p-value resulting from weighing the p-values of the last N farrowings by the chi-square-inverse method. In order to gain specificity, a displacement on the expected non-recirculating NBA and NLP values was used for tuning purposes. With this approach, two PRRSV circulating periods were detected in farm T, which were confirmed with standard laboratorial diagnostic techniques. The method was subsequently validated in farms V1 to V10, where ten PRRSV-recirculating time episodes had been diagnosed. The method proposed here was able to detect the ten PRRSV recirculations using a relatively small set of contiguous farrowings, with only two mismatched weeks, one as a false negative, in farm V1, and one as a false positive, in farm V4. It is concluded that a conditional Poisson-based model of NLP on NBA can be a useful tool for routinely detecting PRRSV recirculation in sow herds.

Machine milking parameters for Murciano-Granadina breed goats.

In dairy ruminants, the combination of milking parameters must ensure good milking performance without harming udder conditions. Commonly, milking conditions for goats are established without having checked the admissible limits for optimal and fast milking. The aim of this study was to establish a limit combination of machine milking parameters that improves machine milking performance without altering milkability or udder status. To this end, we studied the effect of 2 combinations (42 kPa, 120 cpm, 60% vs. 44 kPa, 120 cpm, 60% in terms of kilopascals of vacuum level, cycles per minute of pulsator rate, and percentage of pulsator ratio, respectively) on milk production and composition, milk fractioning during milking, SCC, teat tissue thickness variation after milking, and the milk emission kinetics parameters throughout 1 lactation period (6 mo). The 42 and 44 kPa measured at the vacuum gauge level became average values of 37.5 and 39.3 kPa, respectively, measured at the teat sphincter level during milking. Milk flow significantly increased and total milking time decreased 25 s with the elevation of the vacuum level from 42 to 44 kPa without any adverse effect on milk fractioning at milking. However, the use of 44 kPa also showed an increase in tissue thickness above 5%, and we observed a tendency of average conductivity of milk to increase, although without any adverse effect on SCC. It seems that 44 kPa, 120 cpm, 60% is a possible limit combination of parameters to improve milking performance without altering milkability or udder conditions. We concluded that this combination can be used for milking Murciano-Granadina breed goats in conditions similar to those of this study (mid-level milking system and 1 milking/d), although further studies are necessary to verify its application in the case of 2 milkings/d.

Sperm preparation after freezing improves motile sperm count, motility, and viability in frozen-thawed sperm compared with sperm preparation before freezing-thawing process.

PURPOSE: The aim of this study is to evaluate which cryopreservation protocol, freezing before or after swim-up, optimizes cryopreservation outcomes in terms of motile sperm count, motility, morphology, and viability, and also to establish whether sperm viability could be assessed based on sperm motility. METHODS: Fifty-three fresh and 53 swim-up prepared samples were considered for the first experiment. In parallel, total motility evaluation by CASA system (computer-assisted sperm analyzer) and hypoosmotic swelling test (HOS-test) was performed in each sample to compare the viability results of both methods. In the second experiment, 21 normozoospermic semen samples and 20 semen samples from male factor patients were included. After fresh ejaculate evaluation, the semen sample of each patient was divided into two aliquots, one of them was frozen before swim-up and the other was frozen after swim-up. Motility, sperm count, morphology, and viability were evaluated after thawing. RESULTS: A linear regression model allows prediction of HOS-test viability results based on total motility: HOS = 1.38 + 0.97 · TM (R 2 = 99.10, residual mean squares = 9.51). Freezing before sperm selection leads to higher total and progressive motility, total motile sperm count, and viability rates than when sperm selection is performed before freezing (P < 0.005 in all cases). In fact, sperm selection prior to freezing reaches critical values when subfertile patients are considered. CONCLUSIONS: To conclude, total motility evaluation can predict HOS-test viability results, resulting in a more objective and less time-consuming method to assess viability. In addition, sperm freezing prior to swim-up selection must be considered in order to achieve better outcomes after thawing, especially in patients presenting poor sperm baseline.

Flight behaviour and dispersal of Rhynchophorus ferrugineus (Coleoptera: Dryophthoridae) adults using mark-release-recapture method.

The flight ability and patterns of an insect influence its spread, and the study of its behaviour can be used to improve the strategies to control the pest. Regarding Rhynchophorus ferrugineus (Olivier) (Coleoptera: Dryophthoridae), one of the worst threats to palm trees worldwide, laboratory experiments have been conducted to analyze their flight potential. However, these data must be complemented with tests that allow us to know its flight behaviour and dispersal patterns under field conditions. Two mark-release-recapture experiments were conducted in areas with R. ferrugineus infestations. In the first, the effects of weevil sex, temperature, solar radiation, and relative humidity, on the take-off and flight mobility of adults were analyzed. The second experiment aimed to determine the maximum flight distance covered by adults in field. The take-off rate for R. ferrugineus males was significantly greater than for females, and was positively influenced by temperature (optimum take-off around 25°C) and solar radiation, both factors being highly correlated. Female weevil recaptures were significantly higher, especially as temperatures increased (optimum recapture around 21°C). Dispersal distances of weevil adults increased when temperatures rose, and while this insect tended to fly short distances (<500 m), it was able to cover up to 7 km. The dispersal of R. ferrugineus adults mainly occurred during the first 7 days after their release, and when relative humidity increased, their dispersal time was reduced. The results obtained will permit a more effective implementation of certain measures used to control R. ferrugineus, such as olfactory trapping or intensive surveillance around pest outbreaks.

Supplementing cryopreservation media with reduced glutathione increases fertility and prolificacy of sows inseminated with frozen-thawed boar semen.

The main aim of this work was to evaluate how supplementing freezing media with reduced glutathione (GSH) affected the 'in vivo' fertilizing ability of boar semen subjected to cryopreservation procedures. With this purpose, 12 ejaculates coming from 12 boars were cryopreserved in the presence or absence of 2 mm GSH, whereas the same number of extended ejaculates coming from the same boars was used as negative/farm controls. Eight different sperm parameters (levels of free-cysteine residues in sperm nucleoproteins, DNA fragmentation, sperm viability, acrosome-membrane integrity, intracellular peroxide and superoxide levels, and total and progressive sperm motility) were evaluated before freezing and after 30 and 240 min of thawing. In addition, a total of 180 multiparous sows were used in the field fertility trials, the females being randomly divided into three groups and inseminated with extended, frozen-thawed control or frozen-thawed semen supplemented with 2 mm GSH. The presence of GSH in the freezing media significantly (p < 0.05) increased farrowing rates and the number of total born piglets and alive born piglets, and partially counteracted the cryopreservation-induced damages inflicted on frozen-thawed spermatozoa. We can thus conclude that supplementing freezing media with 2 mm GSH greatly improves boar sperm cryopreservation technology, as it significantly improves the fertilizing ability of frozen-thawed spermatozoa.

Sources of Salmonella contamination during broiler production in Eastern Spain.

Prevention of Salmonella contamination of poultry products requires detailed knowledge of the main sources associated with its presence in the production system. The aims of this study were to determine the main sources of Salmonella contamination in broiler production during growing, to assess the risk factors for Salmonella contamination at the end of the rearing period and to determine the main serovars involved in broiler production systems in Eastern Spain. A total of 65 different broiler houses from different farms were sampled. Each house was sampled at different times during the rearing period. First, when the previous flock was taken to the slaughterhouse, samples of dust, surfaces and previous flock faeces were collected. After cleaning and disinfection (C&D), samples of dust and surfaces were also taken. On the first day of rearing, samples of water, bedding, farming boots, meconiums, delivery-box liners and feed were collected. During rearing, feed samples were taken directly from the truck and from feeders. On slaughter day, samples of dust, surfaces, water, feed and faeces were also collected. Finally, two days after slaughter, carriers (rodents, flies and beetles) were trapped. All samples collected were analysed according to ISO 6579:2002 (Annex D) and positive samples were serotyped in accordance with Kauffman-White-Le-Minor technique. Our results showed that all different types of samples collected were contaminated with Salmonella (prevalence ranged between 1.5% and 38.6%). The most contaminated samples related with poultry production were: delivery-box liners (32.0%), faeces samples (31.2%), dust samples (25.0%), farming boots (19.7%) and feed from feeders (16.0%). However, the most important risk factors for Salmonella contamination of the flocks at the end of the rearing period were Salmonella status of the house after cleaning and disinfection, Salmonella status of day-old chick flocks and feed from feeders. Twenty-one different serovars were isolated from the samples analysed. The most prevalent were in decreasing order: Salmonella Enteritidis (52.9%), S. Hadar (17.8%), S. Virchow (8.9%) and S. Ohio (5.4%). The study suggested that there are many sources for Salmonella contamination and persistence in broiler production. Hence, the whole production chain needs to be controlled to eradicate the bacteria from primary production.

Dose response of lactating dairy ewes during suckling and milking to bovine somatotropin.

The objectives were to determine the effect of administering recombinant bovine ST (bST) every 14 d on milk yield and milk composition in dairy ewes and to assess the possible effects of treatment on milk yield loss that occurs at lamb weaning. Seventy-two lactating dairy ewes were separated into 4 groups at lambing, and each group received no bST (control) or 40, 80, or 120 mg of bST every 14 d until wk 20 of lactation. During the first 5 wk of lactation, ewes suckled their lambs during the night and were milked once daily (period 1). After weaning, from 6 to 22 wk of lactation, ewes were exclusively milked twice daily (period 2). Actual milk yield, potential milk yield, and milk component percentages were recorded weekly throughout lactation. In period 1, bST-treated groups increased yields of potential milk (P = 0.04) and the corresponding 6% fat-corrected milk (FCM; P = 0.04) but not actual milk yield (P = 0.42) compared with the untreated group. In period 2, treated groups increased potential (P < 0.01) and actual (P < 0.01) milk yields as well as their corresponding 6% FCM (potential, P < 0.01; actual, P < 0.01), in comparison with the untreated group. The group treated with 120 mg of bST every 14 d yielded 39% more actual milk and 44% more 6% FCM than the control group for period 2. At weaning, between the last week of period 1 and the first week of period 2, treated groups showed similar absolute (P = 0.15) and relative (P = 0.33) values for the potential milk losses compared with the control group. Treatments increased (P = 0.04) actual milk fat percentages during period 1, but did not affect the other milk components or somatic cell count. In summary, bST increased potential milk yield throughout lactation and actual milk yield only after weaning in dairy ewes. In dairy ewes, bST was not useful for reducing the milk yield loss that occurred at weaning.

Risk assessment of DFD meat due to pre-slaughter conditions in pigs.

A polychotomous logistic regression model was used to identify and assess the risk factors for pork becoming dark, firm and dry meat (DFD). A total of 116 deliveries, comprising 3075 commercial pigs delivered from different farms to five commercial Spanish pig abattoirs were surveyed. The DFD condition was described as an ordinal response variable (normal, moderate and serious) based on measurements of pH(24) in the Semimembranosus muscle. The abattoir, the floor of the lorry, the season, the gender, and the stocking density during transportation influenced the risk of DFD, as well as on-farm fasting time, lairage time and estimated carcass lean content. No effect of the RYR1 gene in the risk of DFD was found. Abattoirs should be especially careful with females slaughtered in winter, where the risk of serious DFD is 4.6% higher than with males slaughtered in summer. The risk of DFD increased with high stocking density and lairage time, and with on-farm fasting times longer than 22h. Our results revealed that lowering the stocking density from 0.37 to 0.50m(2) per 100kg pig during transport would increase the risk of DFD pork by 11%.

Poor prediction value of sperm head morphometry for fertility and litter size in rabbit.

This study was conducted to investigate the predictive capacity of fertility and litter size of sperm head morphometric measurements when the ejaculates fulfilled the minimum requirements commonly used in artificial insemination (AI). Semen samples from 11 rabbits (77 ejaculates) were evaluated for sperm motility, abnormal spermatozoa and sperm head morphometry using computer automated sperm analysis system. Morphometric dimensions for length, width, area and perimeter were analysed. Only ejaculates with more than 70% of motility rate and <15% of abnormal sperm were used for AI. A total of 1031 individual AI were performed in commercial rabbitries. Our results showed significant differences among animals for all sperm head measurements. The mean values for fertility and litter size obtained were 68.4 ± 0.01% and 9.3 ± 0.1% respectively. To assess the predictive value of morphometric dimensions in fertility, a logistic regression analysis was applied. Moreover, multiple linear regression analyses were used to examine the relationship between litter size and sperm head morphometric parameters. Logistic regression analysis rendered a significant model between fertility and area and perimeter, explaining the 0.65% variation. Multiple linear regression analysis rendered a significant model between litter size and width, area and perimeter that explained the 1.3% variation. By conclusion, the sperm head morphometric parameters assay showed low potential to predict fertility and litter size when the ejaculates fulfilled the minimum requirements commonly used in AI (motility and abnormal spermatozoa) in rabbit.

Effects of filtration through Sephadex columns improve overall quality parameters and "in vivo" fertility of subfertile refrigerated boar-semen.

This study was performed to test the effects of filtration through several chromatographic resins on the semen quality parameters (percentages of viability, altered acrosomes and morphological abnormalities, motion characteristics and the response to the Osmotic Resistance Test) of boar ejaculates of poor quality. Our results indicate that filtration through a non-ionic Sephadex resin bed (Sephadex G-15), combined with a glasswool subjection bed, induced an overall improvement of semen quality parameters, especially seen in a significant (P<0.05) decrease in the percentages of morphological abnormalities and an increase of several motility parameters related to velocity and linearity. Similar results, although less intense, were observed when the filtration through G-15 resin was accompanied by an ionically neutral polypropylene disk bed instead of glasswool. On the other hand, filtration through two separate ion-exchange Sephadex resins, cationic C-50 and anionic A-50, have less beneficial, and even detrimental, effects on boar-semen quality. In all cases, filtration was accompanied by a significant (P<0.01) decrease in the final concentration of the samples. Ultrastructural and lectin studies showed that the interaction between sperm and chromatographic resins depends on the resin type utilized, and in the case of G-15 it seems that it works by trapping that sperm with not enough strength to overcome the physical resistance associated with chromatographic particles. When semen of poor quality was filtered through G-15 resin and then was utilized for "in vivo" fertility trials, a significant (P<0.05) increase in the percentage of fertility was observed, when compared with the same, but unfiltered, samples. In summary, our results strongly indicate that filtration through ionically inert, Sephadex chromatographic resins could be a very useful and practical method to improve both boar-semen quality and fertilizing ability, especially from mediocre and/or subfertile samples.

Risk assessment of skin damage due to pre-slaughter conditions and RYR1 gene in pigs.

A polychotomous logistic regression was used to assess the risk factors for skin damage prior to slaughter. A total of 116 deliveries (15,695 pigs) from commercial farms to five Spanish pig abattoirs were surveyed. The skin damage condition was described as an ordinal response (1: no damage; 2: very slight damage; and 3: slight or more damage). The abattoir by the season (p<0.01), the floor surface of the lorry (p=0.02), and the mixing of unfamiliar pigs at loading (p=0.01) influenced the occurrence of skin blemishes. Skin damage increased with on-farm fasting time (p<0.01), loading time (p<0.01), lairage time (p<0.01), as well as with carcass weight (p<0.01). In winter transports the risk of skin damage decreased (p<0.01) at higher space allowance in the lorry. The risk of developing PSE and DFD pork increased with the skin damage score (p<0.01). The nn genotype for the RYR1 gene was less prone to skin damage but at the same time it is more sensitive to skin damage in relation to PSE risk. It is concluded that the skin damage score can be used as a rapid indicator of animal welfare and pork quality.

Effects of hCG as spermiation inducer on European eel semen quality.

Fish sperm quality has traditionally been estimated by subjective evaluation of motility and sperm concentration. Alternative methods for evaluation of sperm quality have been developed in the last decade and enable estimation of spermatozoa head morphometry, membrane integrity and mitochondrial function. Weekly injections of human chorionic gonadotropin (hCG) induced spermiation in farmed male European eels. The milt volume increased from the 5th to 12th weeks. Sperm concentration significantly increased from the 5th week, reaching the highest values at the 8th week, while best motility results were registered at the 9th week of treatment. Coinciding with these intervals, the percentage of dead spermatozoa determined with Hoechst staining showed a reduction in the 8th to 11th weeks of treatment, while the percentage of mitochondrial functionality determined by JC-1 staining did not show a similar pattern. The automatic sperm morphology analysis (ASMA) of the spermatozoa head length, width, area and perimeter showed a significant growth from the 5th to 8th weeks. However, the analysis of isolated descriptive parameters may be difficult to understand because there is a variability in these parameters for each week, making knowledge of the growth kinetic complex. The global size of the spermatozoa head was calculated by applying principal component analysis (PCA), because this method establishes new components that make the interpretation of results easier, allowing a whole interpretation of the changes in the cell morphology. PC1 defines the global head size and shows a significant increase between the 5th and 8th weeks of treatment, showing shorter changes until 12th week. PC2 shows a significant increase in the spermatozoa width from the 5th to 7th weeks. Considering the results of the variations in the principal components defining European eel spermatozoa morphometry, it may be concluded that hCG maturative treatment produced thick cells during the first weeks of spermiation, and subsequent samplings showed an increase in cell width and length. These changes in sperm morphometry coincide with the highest sperm quality assessed as sperm motility and concentration, as well as with the best results obtained in previous studies reporting the best sperm quality between weeks 8 and 10 of hCG treatment. These results support the use of ASMA and Hoechst staining techniques as alternative methods for the evaluation of fish sperm quality.

Morphometric changes in goat sperm heads induced by cryopreservation.

Two experiments were designed to evaluate the effect of cryopreservation on morphometric characteristics of the goat sperm head. To address this question, we evaluated the size of the sperm head in fresh control cells, post-cooling cells after equilibration with the glycerol preservation solution, and post-thawing cells. Assessment was by automated morphometric sperm head analysis (ASMA) using phase-contrast microscopy without staining. In the first experiment, ASMA was performed on heterospermic pooled samples (fresh, post-cooling after equilibration with the glycerol preservation solution and post-thawing): length, width, area and perimeter were measured. In the second experiment, sperm viability was assessed by Hoechst staining and head morphometry was carried out as before, simultaneously during the cryopreservation process, and the head size was identified for both live and dead spermatozoa. The data were analysed by principal component analysis (PCA). The purpose of PCA is to derive a small number of linear combinations (principal components) from a set of variables (length, width, area and perimeter), that retain as much of the information in the original variables as possible. The main findings that have emerged from this study are that (i) a simple procedure has been developed for measuring spermatozoa heads without staining, which minimises the possibility that sperm head dimensions were influenced by procedural artefacts; (ii) the dimensions of goat sperm heads after cryopreservation in skimmed milk-glucose medium were smaller than in fresh sperm, but this was due to the equilibration phase with the cryoprotectant and not to the cryopreservation process itself; and (iii) dead spermatozoa showed smaller heads than live sperm, consequent upon the loss of membrane function. No differences were observed between post-cooling cells after equilibration with the glycerol preservation solution and post-thawing spermatozoa and only minor osmotic differences between them and fresh sperm were observed.

Risk assessment of PSE condition due to pre-slaughter conditions and RYR1 gene in pigs.

A polychotomous logistic regression model was used to identify and assess the risk factors for pork meat becoming pale, soft and exudative (PSE). A total of 116 deliveries, comprising 15,695 commercial pigs delivered from different commercial farms to five Spanish pig commercial abattoirs were surveyed. The PSE condition was described as an ordinal response variable (normal, prone to PSE and PSE) based on measurements of electrical conductivity in the Semimembranosus muscle 1-2 h post-mortem. The RYR1 genotype, the abattoir, the season, the gender, the floor surface in the lorry, the loading system, and the stocking density during transportation influenced the risk of PSE condition, as well as on-farm fasting time, loading time, transportation and lairage times. The effect of the RYR1 gene, determined in a subsample of 1331 pigs, was due to nn stress-susceptible pigs, in which the risk of PSE meat (PQM>6 µs) increased fourfold. Abattoirs should be especially careful in summer, when the risk of PSE meat was found to be double that of winter. The risk of PSE meat decreased with the time of transportation, though its effect depended on the stocking density. Thus, our results indicate that, for transits longer than 3 h, the risk of PSE increases with stocking density during transport, while the opposite occurs for shorter transits.

Evaluation of screening test for detection of antimicrobial residues in ewe milk.

The effects of preservatives (potassium dichromate and sodium azide), heat treatment (untreated and 82 degrees C/10 min), and lactation stage upon the response of the microbial tests (BRT AiM and Delvotest) utilized for the detection of residues of antimicrobial substances in ewe milk were examined. Milk samples were collected from the morning milking of 50 Manchega ewes every 2 wk, from 15 d postpartum until the end of lactation. A total of 2322 samples were analyzed by BRT AiM with prediffusion and Delvotest microbial tests. The specificity of preservative-free milk samples without heat treatment was high (96.3% for BRT and 97.7% for Delvotest), with results improving for those samples thermally treated at 82 degrees C/10 min (99.0% for BRT and 98.7% for Delvotest). Potassium dichromate produced a total inhibition of growth of Bacillus stearothermophilus with both methods. When acidiol was utilized, the specificity of the samples not treated thermally was lower compared with preservative-free milk samples for the BRT AiM (90.2%) and Delvotest (91.0%) methods, improving when the samples were thermally treated, both for BRT AiM (94.8%) and Delvotest (95.3%), given that the presence of the preservative increased the frequency of doubtful results. The lactation stage significantly affected the results of the methods, with a greater frequency of false-positive and doubtful cases toward the end of the cycle, especially in those samples preserved with acidiol. The greater selectivity in both methods was therefore obtained for preservative-free ewe milk samples with prior heat treatment taken at the beginning or in midlactation period.

Detection limits of antimicrobials in ewe milk by delvotest photometric measurements.

The Delvotest method detection limits per manufacturer's instructions at a fixed reading time of 3 h for 24 antimicrobial agents were determined in ewe milk by photometric measurement. For each drug, eight concentrations were tested on 20 ewe milk samples from individual ewes. Detection limits, determined by means of logistic regression models, were (microg/kg): 3, amoxycillin; 2, ampicillin; 18, cloxacillin; 1, penicillin "G"; 34, cefadroxil; 430, cephalosporin "C"; 40, cephalexin; 20, cefoperazone; 33, Ceftiofur; 18, cefuroxime; 6100, streptomycin; 1200, gentamycin; 2600, neomycin; 830, erythromycin; 100, tylosin; 180, doxycycline; 320, oxytetracycline; 590, tetracycline; 88, sulfadiazine; 44, sulfamethoxazole; 140, sulfametoxypyridazine; 48, sulfaquinoxaline; 12,000, chloramphenicol; and 290, trimethoprim. Whereas the beta-lactam antibiotics, sulphonamides, and tylosin were detected by Delvotest method at levels equal to those of maximum residue limits, its sensitivity needs to be enhanced to detect aminoglycosides, tetracyclines, streptomycin, chloramphenicol, and trimethoprim residues in ewe milk or to develop an integrated residue detection system for ewe milk with different sensitive microorganisms for each group of antiinfectious agents.

Influence of vacuum level and overmilking on udder health and teat thickness changes in dairy ewes.

The effects of vacuum level and overmilking on udder health were studied in ewes. Vacuum levels of 36 and 42 kPa were assigned to two groups of 23 Manchega ewes in a crossover study design with two experimental periods of 5 wk for each. Moreover, for each ewe, one teat was overmilked 1.5 to 2 min at all milkings during these 10 wk. The milking machine used had a midlevel milkline and pulsation was fixed at 180 cycles per min and a pulsation ratio of 50:50. Bacterial exposure of all teats was increased by dipping them in a suspension of Staphylococcus simulans at eight milkings of each period. New intramammary infections (IMI) were not significantly affected by the vacuum level used (18 and 23% of ewes infected, at 36 and 42 kPa, respectively) or application of overmilking (9 and 11% of half udders infected without and with overmilking, respectively). Likewise, neither factor significantly affected the somatic cell count (SCC) of the milk. Teat thickness changes after milking varied significantly due to the presence of overmilking (-13.6 and -7.4%, in teats not overmilked and overmilked, respectively) but were not affected by vacuum level. At no time were any lesions or variations visibly noted in the teat walls or orifice. So, in this work we were unable to demonstrate that the vacuum and overmilking levels assayed, both used with a pulsation rate of 180 cycles/min, have an important effect on the state of udder health in the short term. Furthermore, it was also observed that, in absence of IMI, the two factors studied did not cause irritation of any kind in the gland that might influence the SCC of the milk.

Bovine somatotropin dose titration in lactating dairy ewes. 3. Treatment interval.

Seventy-four lactating dairy ewes were injected with recombinant bovine somatotropin (bST; sometribove) in a sustained-release formulation. Ewes received 0, 80, 160, or 240 mg of bST/14 d at the end of 2, 4, and 6 wk postlambing, after which injections were withheld for a 28-d period. Response of milk production to bST presented a positive linear contrast and a negative quadratic contrast. After the final injection of bST (d 0), an increase in daily milk production was observed until d +9. A continuous decrease followed with milk production returned to control levels on d +11, +18, and +20, for 80, 160, and 240 mg of bST/14 d. Milk protein content decreased gradually until d +8 before it returned to control levels on d +12, +14 and +14, for 80, 160, and 240 mg of bST/14 d. Levels of bST and IGF-I in plasma presented positive and highly significant linear contrasts and negative quadratics which were significant only for bST. Relative to the evolution of milk production, the evolution of IGF-I levels in plasma was more similar than that of bST, although the correlation of each measure with milk production was high and highly significant. It was concluded that the period between successive injections should be shorter the lower the dose employed; however, a 14-d period seemed to correspond correctly for the dosages and hormone formulation tested.

Multivariate analysis applied to tomato hybrid production.

Twenty characters were measured on 60 tomato varieties cultivated in the open-air and in polyethylene plastic-house. Data were analyzed by means of principal components, factorial discriminant methods, Mahalanobis D(2) distances and principal coordinate techniques. Factorial discriminant and Mahalanobis D(2) distances methods, both of which require collecting data plant by plant, lead to similar conclusions as the principal components method that only requires taking data by plots. Characters that make up the principal components in both environments studied are the same, although the relative importance of each one of them varies within the principal components. By combining information supplied by multivariate analysis with the inheritance mode of characters, crossings among cultivars can be experimented with that will produce heterotic hybrids showing characters within previously established limits.