Association between single nucleotide polymorphisms in p53 and abortion in Thoroughbred mares

Single nucleotide polymorphisms (SNPs) in the p53 gene have been studied extensively in humans. The aims of this study were to determine the frequency of the Arg/Pro SNP in p53 in Thoroughbred mares on one stud in Brazil and to correlate p53 genotypes with reproductive performance. SNPs were detected by PCR-restriction fragment length polymorphism in blood samples from 105 horses and confirmed by sequencing. The allele frequency in Thoroughbred mares at codon 72 in exon 4 was 73.3% Arg/Pro, 17.1% Arg/Arg and 9.6% Pro/Pro. The presence of Arg/Pro was significantly associated with abortion (P=0.02), while Pro/Pro mares had a lower probability of abortion (P<0.05). Using a logistic regression model, the dominance effect was significant (P=0.044; odds ratio 7.94) for abortion and additive effects were not significant (P=0.26). p53 may play a role in equine reproduction.     

Appraising the Shelf Life of Farmed Cobia,Rachycentron canadum,by Application of a Quality Index Method

Freshness is the main concern of seafood quality, and the principal method to evaluate seafood freshness is sensory evaluation. The aim of this work was to study the quality changes of cobia, Rachycentron canadum, under ice storage through sensory and physical analysis as well as bacterial counting of specific spoilage organisms (SSOs). In particular, the utilization of a quality index method (QIM) scheme was proposed. Samples stored for 0–30 d were analyzed with the QIM. Ten panelists observed and registered the changes occurring in the fish starting on day zero and ending when the fish were spoiled. After developing the scheme, 11 sensory attributes were described in 23 points, which detailed the appearance of skin, eyes, abdomen, gills, and flesh deterioration. The volatile nitrogen compound measurements and microbiological data of the SSOs determined a shelf‐life of 19 d for the samples. Sensory analysis showed a rejection point at 15.67 d of ice storage. The natural degradation of myofibrillar proteins and collagen was observed during ice storage. In conclusion, a shelf‐life of 15 d was defined for raw cobia stored on ice.     

Phenotypic and Genotypic Characterization of Salmonella enterica in Captive Wildlife and Exotic Animal Species in Ohio,USA

The purpose of this study was to investigate the occurrence, antimicrobial resistance patterns, phenotypic and genotypic relatedness of Salmonella enterica recovered from captive wildlife host species and in the environment in Ohio, USA. A total of 319 samples including faecal (n = 225), feed (n = 38) and environmental (n = 56) were collected from 32 different wild and exotic animal species in captivity and their environment in Ohio. Salmonellae were isolated using conventional culture methods and tested for antimicrobial susceptibility with the Kirby–Bauer disc diffusion method. Salmonella isolates were serotyped, and genotyping was performed using the pulsed‐field gel electrophoresis (PFGE). Salmonella was detected in 56 of 225 (24.9%) faecal samples; six of 56 (10.7%) environmental samples and six of 38 (15.8%) feed samples. Salmonella was more commonly isolated in faecal samples from giraffes (78.2%; 36/46), cranes (75%; 3/4) and raccoons (75%; 3/4). Salmonella enterica serotypes of known public health significance including S. Typhimurium (64.3%), S. Newport (32.1%) and S. Heidelberg (5.3%) were identified. While the majority of the Salmonella isolates were pan‐susceptible (88.2%; 60 of 68), multidrug‐resistant strains including penta‐resistant type, AmStTeKmGm (8.8%; six of 68) were detected. Genotypic diversity was found among S. Typhimurium isolates. The identification of clonally related Salmonella isolates from environment and faeces suggests that indirect transmission of Salmonella among hosts via environmental contamination is an important concern to workers, visitors and other wildlife. Results of this study show the diversity of Salmonella serovars and public health implications of human exposure from wildlife reservoirs.     

Vegetation indices and NIR-SWIR spectral bands as a phenotyping tool for water status determination in soybean

Precision Agriculture - Drought is one of the main limiting factors of soybean production. The great deal of time and effort that current available phenotyping methods demand hampers the selection...     

Treatment of anovulatory anoestrous postpartum dairy cows with a gonadotropin-releasing hormone (GnRH), prostaglandin F2𝛂, GnRH regimen or with progesterone and oestradiol benzoate

AIM: To compare 2 treatments for anovulatory anoestrus (AA) in postpartum dairy cows. The treatments were combinations of gonadotropin-releasing hormone (GnRH) and prostaglandin F_2𝛂 (PG) or progesterone (P4) and oestradiol benzoate (ODB).

METHODS: Forty AA cows from each of 5 herds were blocked by age (2 or >2 years old) and randomly assigned to 1 of 2 treatments. The first group (GPG) were treated with 250 𝛍g of a GnRH analogue, gonadorelin, followed 7 days later by 15 mg of the PG analogue, luprostiol. Two days later the cows were injected with 250 𝛍g of gonadorelin. Cows were artificially inseminated 16–24 h after the second GnRH injection. The second group (P4+ODB) were treated with an intravaginal P4 releasing device for 6 days, followed 24 h after device removal by injection of 1 mg of ODB. Cows were pregnancy tested 35–40 days after the initial insemination and twice again at 6–8 week intervals thereafter.

RESULTS: There was no significant difference between P4+ODB and GPG groups in the percentage of cows submitted for insemination in the first 7 days (94.0% vs 100% for P4+ODB vs GPG, respectively; p>0.3), in conception rate to first insemination within the first 7 days (43.6% vs 35.0% for P4+ODB vs GPG, respectively; p>0.2), in the percentage of cows conceiving in the first 28 days of the breeding period (68.0% vs 58.3%, P4+ODB vs GPG, respectively; p>0.1), or in median interval from the end of treatment to conception (20 vs 21days;p>0.1).

CONCLUSIONS: No differences in the reproductive performance of AA cows treated with either P4+ODB or GPG were detected. However, given the small number of animals enrolled, further data are required before the GPG protocol can be recommended for treatment of AA cows.     

Pregnancy loss in dairy cattle in the Waikato region of New Zealand

AIM: To define the incidence rate of pregnancy loss and risk factors for those losses in pasture-fed dairy cattle in the Waikato region of New Zealand.

METHODS: Cows (n=2,004) from 10 pasture-fed, spring-calving dairy herds in the Waikato were enrolled following confirmation of pregnancy 29–45 days after insemination, for inseminations that occurred within the first 16 days of the seasonal breeding period. Transrectal ultrasonographic examinations for pregnancy were conducted at approximately 6, 8, 10, 14 and 22 weeks gestation, and subsequent calving data were recovered. Pregnancy loss was defined as having occurred when a confirmed pregnancy was not rediagnosed, when gross abortion was detected, or when a cow calved <265 days after the confirmed conception date. Data were analysed using reverse stepwise logistic regression and Cox's proportional hazards analysis.

RESULTS: A total of 128 (6.4%) pregnancy losses were detected. The incidence rate was higher in early compared to late gestation (10.9 vs 2.8 losses/10,000 cow-days between Weeks 6–10 vs Weeks 10–14, respectively; p<0.001). Higher rates of loss were associated with the occurrence of clinical mastitis (Hazards ratio (HR)=1.57; p=0.071), being treated for anoestrus (HR=1.69; p=0.007), and in cows that had calving-to-conception intervals ≤63 days compared with those that had calving-to-conception intervals >92 days (HR=2.49; p=0.06). In addition, the rate of pregnancy loss differed between herds (p=0.05).

CONCLUSIONS: The highest rate of pregnancy loss occurred in early gestation. Clinical mastitis, anoestrus and calving late in the calving season were risk factors for pregnancy loss.

CLINICAL RELEVANCE: Pregnancy diagnosis using ultrasonography can be undertaken from 28 days post-insemination. However, due to the high rate of pregnancy loss at this stage of gestation, herdowners need to be warned of possible losses, and cows should be re-examined to confirm pregnancy before certification of pregnancy status is given.     

Effect of Ascorbic Acid Concentrations,Methods of Cooling and Freezing on Boer Goat Semen Cryopreservation

To improve the Boer goat semen quality during cryopreservation process, three experiments were carried out to investigate the effect of (i) different concentration of ascorbic acid supplementation (ii) rate of cooling with chilled semen characteristics and (iii) method of freezing on post‐thaw Boer goat sperm using Tris‐based extender. Ascorbic acid at 8.5 mg/ml improved the sperm parameters (motility, integrity of membrane and acrosome, morphology and viability), compared to control in cooled samples (p < 0.05). With regard to other concentrations and post‐thawed parameters, ascorbic acid at 2.5–8.5 mg/ml led to higher percentages of sperm motility and integrities of membrane and acrosome when compared to control (p < 0.05). Slow cooling rises to higher percentages of sperm motility, acrosome integrity and viability, in comparison with fast cooling, in terms of cooled and frozen samples (p < 0.05). Programmable freezing method produced the higher percentages of sperm motility, integrities of membrane and acrosome and viability when compared to the freezing method of polystyrene box during goat sperm freezing (p < 0.05). In conclusion, chilled and post‐thawed sperm quality of Boer goat was improved when a Tris‐based extender supplemented with ascorbic acid was used at stages of different cooling rates and freezing methods.     

Validation of a subjective counting method for a horn flies (Haematobia irritans irritans) (Diptera: Muscidae) population in a cattle herd

A trained observer direct count method to measure horn fly population was evaluated to determine the reliability (inter-observer agreement) and its validity when compared with a "gold standard" method (video film). All the counts were performed with the animals restrained in a chute in a single herd. A direct count of horn flies by each of two observers on opposite sides of the animal was made. In addition a videotape recording of the counting surface on each animal was made. Horn flies were counted on 80 cows in the morning twice monthly from 22 October 1999 to 24 March 2000. The correlation between observer counts was high as was the correlation between observer counts and counts made from a videotape recording. Direct counts by trained observers were highly reliable and had good validity. However, videotape recording can be useful when the horn fly population is high, because it is faster in the field than the direct count method. The results of this study suggest that the direct count method can be used with confidence under field conditions.     

Pre-emptive epidural ketamine or S(+)-ketamine in post-incisional pain in dogs: a comparative study

OBJECTIVE: To compare the pre-emptive analgesic effects of epidural ketamine or S(+)-ketamine on post-incisional hyperalgesia. STUDY DESIGN: Prospective randomized study. ANIMALS: Twenty-four mongrel dogs (1-5 years, weighing 11.9+/-1.8 kg). METHODS: Dogs were anesthetized with propofol (5 mg/kg intravenously) and a lumbosacral epidural catheter was placed. Dogs were randomly allocated to 3 groups, each with 8 dogs. The control group (CG) was administered saline solution (0.3 mL/kg); the ketamine group (KG) ketamine (0.6 mg/kg); and the S(+)-ketamine group (SG) S(+)-ketamine (0.6 mg/kg). The final volume was adjusted to 0.3 mL/kg in all groups. Five minutes after the epidural injection a surgical incision was made in the common pad of the right hind limb and was immediately closed with simple interrupted nylon suture. Respiratory (RR) and heart (HR) rates, rectal temperature (T), sedation (S), lameness score, and mechanical nociceptive threshold by von Frey filaments were evaluated before the propofol anesthesia and at 15, 30, 45, 60, 75, and 90 minutes and then at 2, 4, 6, 8, 12, and 24 hours after epidural injection. RESULTS: There were no differences in RR, HR, T, or S between groups. Motor blockade of the hind limbs was observed during 20+/-3.6 minutes in KG and during 30.6+/-7.5 minutes in SG (mean+/-SD). Mechanical force applied to obtain an aversive response was higher from 45 minutes to 12 hours in KG and from 60 to 90 minutes in SG, when compared with CG. CONCLUSIONS: Pre-emptive epidural ketamine induced no alterations in RR and HR, and reduced post-incisional hyperalgesia for a longer time than did S(+) ketamine. CLINICAL RELEVANCE: Although anesthetic and analgesic potency of S(+) ketamine is twice that of ketamine, the racemic form is seemingly better for post-incisional hyperalgesia.     

Seroprevalence and molecular evidence for the presence of bovine immunodeficiency virus in Brazilian cattle

Data on the worldwide distribution of bovine immunodeficiency virus (BIV) and bovine leukemia virus (BLV) is limited. A prevalence study of antibodies to BIV and BLV was conducted in six different cattle herds in Brazil. Out of a total of 238 sera analyzed, 11.7% were found positive for anti-BIV p26 antibodies as determined by Western blot analysis, 2.1% were positive for anti-BLV gp51 antibodies as detected by immunodiffusion test. Peripheral blood mononuclear cells from BIV seropositive cattle were found to have BIV-provirus DNA, as detected by nested polymerase chain reaction. A nucleotide sequence corresponding to a 298 bp fragment of the BIV pol gene was also analyzed. Amino acid sequences of these Brazilian pol gene products showed 98.0 to 100% homology to the American strain BIV R29, 97.0 to 99.0% to Japanese BIV isolates, and divergence ranged from 0 to 4.0% among Brazilian BIV isolates. This evidence of the presence of BIV and BLV infections in Brazil should be considered a health risk to Brazilian cattle populations and a potential causative agent of chronic disease in cattle.