Digestion and metabolism of low and high residual feed intake Nellore bulls

Understanding the reasons why animals of similar performances have different feed requirements is important to increase profits for cattle producers and to decrease the environmental footprint of beef cattle production. This study was carried out aiming to identify the associations between residual feed intake (RFI) and animal performance, nutrient digestibility, and blood metabolites related to energy balance of young Nellore bulls during the finishing period. Animals previously classified as low (n?=?13) and high RFI (n?=?12), with average initial body weight of 398 kg and age of 503 days were used. Cattle were fed a high energy diet and were slaughtered when rib fat thickness measured by ultrasound between the 12th and 13th ribs reached the minimum of 4 mm. A completely randomized design was adopted, being data analyzed with a mixed model that included the random effect of slaughter group, the fixed effect of RFI class, and linear effect of the covariate feedlot time. No differences were found (p?>?0.10) between RFI classes for performance, dry matter, and nutrients intake. However, dry (p?=?0.0911) and organic matter (p?=?0.0876) digestibility tended to be lower, and digestibility of neutral detergent fiber corrected for ash and protein (p?=?0.0017), and total digestible nutrients (p?=?0.0657) were lower for high RFI animals, indicating lesser capacity of food utilization. Difference between low and high RFI animals was also found for blood cortisol at the end of the trial (p?=?0.0044), having low RFI animals lower cortisol concentrations. Differences in the ability to digest food can affect the efficiency of transforming feed into meat by Nellore cattle.     

Risk factors and indicators of reduced welfare of grazing dairy cows from selected smallholder dairy farms in Midlands Province,Zimbabwe

Zimbabwe’s smallholder dairying faces many challenges that affect the welfare of dairy cows; however, the status of this welfare has not yet been determined. A cross-sectional study was conducted in Midlands Province on 41 active smallholder dairy farms with 86 cows in winter and summer to determine the risk factors and indicators to impaired cow welfare. These objectives were achieved using farmer questionnaires and direct observations. Eleven percent of the observed cows were severely lame in summer while only 5% were severely lame in winter. Lameness was significantly associated with season, absence of shade, breed, and low dipping frequency; 58% of the cows had low body condition scores (BC?<?3) and this low BC was associated with low frequency of protein (p?=?0.002) and vitamin (p?=?0.012) supplementation recorded in more than 52% of the farms visited. In winter, only 11% of the observed cows were heavily soiled (score 3), while in summer 64% of the cows were heavily soiled and this was associated with slurry accumulation in more than 80% of the observed cattle pens as well as the study season (p?<?0.001). A quarter (26%) of the studied animals had visible teat lesions on the teat skin and this was associated with the type of lubricant used (p?=?0.011). Only 34% of the cows allowed an approaching stockman to touch them and this was associated with shouting (p?=?0.012) and whipping of cows (p?=?0.002). The study concluded that welfare of dairy cows was poor in most of the smallholder dairy farms studied.     

The effect of ammonia on canine polymorphonuclear cells

Hyperammonaemia is a common complication of liver disease in dogs. High concentrations of ammonia can be detrimental to dogs with liver disease for several reasons, notably by causing hepatic encephalopathy (HE) which describes the wide range of neurological abnormalities ranging from altered behaviour to seizures that are well recognised complications in dogs with hepatic disorders. In human patients with liver disease, hyperammonaemia has also been linked to the development of other systemic complications such as dysregulation of the innate immune system. In contrast, the effects of hyperammonaemia on the canine innate immune system is currently unknown. The aim of this study was to investigate the effects of ammonia on the oxidative burst activity of canine polymorphonuclear cells in vitro. Blood obtained from healthy dogs (n?=?8) was incubated with escalating concentrations of ammonia ranging from 0 to 250 μM, and the percentage of cells experiencing an oxidative burst was evaluated using a commercial kit (Phagoburst?) and flow cytometry. The spontaneous oxidative burst was evaluated without stimulation and also following stimulation with E coli. The pH of the blood was also measured at the differing ammonia concentrations. There was an increase in the percentage of cells experiencing a spontaneous oxidative burst from ammonia concentrations of 125 μM (p?=?<0.05) and above (p?=?<0.01), with a 4.9 fold increase at 200 μM (p?=?< 0.001). In those cells stimulated with E coli, incubation with increasing ammonia concentrations did not result in a significant difference in oxidative burst from baseline (p?=?0.953). There was no statistically significant difference between the pH of the blood at the various ammonia concentrations (p?=?0.2) suggesting that the difference in spontaneous oxidative burst was due to the ammonia rather than simply a change in pH conditions. In summary, the spontaneous oxidative burst of neutrophils was significantly increased from baseline. This supports a potential role of ammonia in contributing to innate immune system dysfunction in dogs with liver disease, and may present a future therapeutic target.     

Antimicrobial susceptibility and phylotyping profile of pathogenic <Emphasis Type="Italic">Escherichia coli</Emphasis> and <Emphasis Type="Italic">Salmonella enterica</Emphasis> isolates from calves and pigs in Minas Gerais,Brazil

The aims of the present study were to determine (i) the profiles of phylogroup and (ii) the antimicrobial susceptibility of pathogenic Escherichia coli strains isolated from calves, and of Salmonella spp. strains isolated from calves and pigs in Minas Gerais State, Brazil. Sixty-one pathogenic E. coli strains and Salmonella spp. (n?=?24) strains isolated from fecal samples of calves and Salmonella spp. (n?=?39) strains previously isolated from fecal samples of growing/finishing pigs were tested. The minimum inhibitory concentration (MIC) using the agar dilution method was determined for nalidixic acid, amikacin, amoxicillin, ampicillin, cefoxitin, norfloxacin, gentamicin, tetracycline, and trimethoprim-sulfamethoxazole. All E. coli isolates were susceptible to amikacin. Tetracycline was the antimicrobial that presented the higher frequency of resistance among E. coli strains, followed by ampicillin, trimethoprim-sulfamethoxazole, amoxicillin, nalidixic acid, norfloxacin, gentamicin, and cefoxitin. E. coli (n?=?61) strains isolated from calves belonged to different phylogroup namely, phylogroup A (n?=?26), phylogroup B1 (n?=?31), phylogroup E (n?=?3), and phylogroup F (n?=?1). Phylogroups B2, C, and D were not identified among the E. coli in the present study. All Salmonella spp. (n?=?24) strains isolated from fecal samples of calves were susceptible to amikacin, amoxicillin, ampicillin, norfloxacin, gentamicin, tetracycline, and trimethoprim-sulfamethoxazole. Resistance to nalidixic acid and cefoxitin was detected in 16.66 and 8.33 % of the Salmonella spp. strains, respectively. Among the Salmonella spp. (n?=?39) strains isolated from fecal samples of pigs, the higher frequency of resistance was observed to tetracycline, followed by amoxicillin, gentamicin, ampicillin, trimethoprim-sulfamethoxazole, nalidixic acid, cefoxitin, and norfloxacin. All strains were susceptible to amikacin. Forty-eight (78.68 %) of the E. coli strains were classified as multidrug-resistant, whereas among Salmonella spp. strains, the percentage of multidrug resistance was 57.14 %, being all multidrug-resistant strains isolated from pigs (92.30 %). The results from the present study indicate a high frequency of antimicrobial resistance among pathogenic E. coli strains isolated from calves and Salmonella spp. strains isolated from pigs and a high rate of susceptibility to most antimicrobials tested among Salmonella spp. strains isolated from calves. Our study highlights the presence of multidrug-resistant strains of E. coli and Salmonella spp. isolated from food-producing animals in Minas Gerais, Brazil.     

Molecular detection of <Emphasis Type="Italic">Chlamydophila abortus</Emphasis>, <Emphasis Type="Italic">Coxiella burnetii</Emphasis>, and <Emphasis Type="Italic">Mycoplasma agalactiae</Emphasis> in small ruminants’ aborted fetuses in southern Iran

Abortion in sheep and goats has become increasingly important worldwide because of the significant economic losses and potential zoonotic implication of commonly involved pathogens. Therefore, this cross-sectional study was conducted in southern Iran to detect the Chlamydophila abortus and Coxiella burnetii, as zoonotic pathogens, and Mycoplasma agalactiae, as a neglected abortifacient agent in small ruminants’ aborted fetuses, by using polymerase chain reaction (PCR). From a total of 300 aborted fetuses (183 sheep and 117 goats), 46 samples (15.5%) were positive by PCR, 11% for C. abortus, 2% for C. burnetii, and 3% for M. agalactiae. Also, the association of suggested risk factors with abortion due to these bacterial agents was investigated using univariable and multivariable logistic regression. Results of the statistical analysis showed significant association of C. abortus with flock size (OR?=?2.82, P?=?0.014), season (P?<?0.05), and the number of pregnancy in the aborted dam (OR?=?2.5, P?=?0.05). Our results indicated that C. abortus has a relatively substantial role in small ruminant abortions, and C. burnetii and M. agalactiae are likely important abortifacient agents in our region, too. Regarding veterinary and/or public health importance of these bacterial agents, more attention from veterinary and/or human health services and, maybe, a surveillance system for control and prevention of them are recommended.     

Antimicrobial resistance and virulence profile of enterococci isolated from poultry and cattle sources in Nigeria

This study investigated the occurrence, antimicrobial resistance and virulence of Enterococcus from poultry and cattle farms. Three hundred and ninety samples: cloacal/rectal swabs (n?=?260) and manure (n?=?130] were processed for recovery of Enterococcus species. Standard bacteriological methods were used to isolate, identify and characterize Enterococcus species for antimicrobial susceptibility and expression of virulence traits. Detection of antibiotic resistance and virulence genes was carried out by polymerase chain reaction. Enterococcus was recovered from 167 (42.8%) of the 390 samples tested with a predominance of Enterococcus faecium (27.7%). Other species detected were Enterococcus gallinarum, Enterococcus faecalis, Enterococcus hirae, Enterococcus raffinosus, Enterococcus avium, Enterococcus casseliflavus, Enterococcus mundtii and Enterococcus durans. All the isolates tested were susceptible to vancomycin, but resistance to tetracycline, erythromycin, ampicillin and gentamicin was also observed among 61.0, 61.0, 45.1 and 32.7% of the isolates, respectively. Sixty (53.1%) of the isolates were multidrug resistant presenting as 24 different resistance patterns with resistance to gentamicin-erythromycin-streptomycin-tetracycline (CN-ERY-STR-TET) being the most common (n?=?11) pattern. In addition to expression of virulence traits (haemolysin, gelatinase, biofilm production), antibiotic resistance (tetK, tetL, tetM, tetO and ermB) and virulence (asa1, gelE, cylA) genes were detected among the isolates. Also, in vitro transfer of resistance determinants was observed among 75% of the isolates tested. Our data revealed poultry, cattle and manure in this area are hosts to varying Enterococcus species harbouring virulence and resistance determinants that can be transferred to other organisms and also are important for causing nosocomial infection.     

In vitro control of parasitic nematodes of small ruminants using some plant species containing flavonoids

This study determined in vitro anthelmintic efficacy of three plant species: Trema orientalis, Urtica dioica and Zanthozylum capense on nematode larvae of small ruminants. Dried leaf samples (40 g) were extracted in 70% ethanol, in portions of 10 g and concentrated to 100 ml. Half and one quarter of the original crude extract were both made to 100 ml. Rectal faecal material from 10 Merino sheep and 25 Nguni goats was pooled within species and thoroughly hand-mixed. Dung samples, each of 5 g were cultured for 12 days at 27 °C. On day 13, 4 plates were watered and 4 others treated with ethanol to correct for solvent effect on mortality. The design was 2 (animal species)?×?3 (plant species)?×?3 (extract concentrations). In each of three runs, three plates were treated with each crude extract in three incremental concentrations. Surviving L3 larvae were isolated, counted and mortalities became indices of anthelmintic efficacy. Data from nematode larval mortality were analysed to determine the effect of animal species, plant species, concentration and their interactions. Efficacy was affected by concentration (P?=?0.0001), animal species (P?=?0.0046), plant species (P?=?0.0572), the interactions of animal species and concentration (P?=?0.0010), plant species and concentration (P?=?0.0123) and concentration × animal × plant species (P?=?0.0435).     

Improving smallholder cattle reproductive efficiency in Cambodia to address expanding regional beef demand

This study aimed to identify factors associated with cattle reproductive output in rural smallholder farms in Cambodia in order to determine the main causes of reproductive failure and design efficient interventions for improvement. The majority of the nation’s beef is produced on smallholder farms where productivity is constrained by poor animal reproductivity reflected in the recent livestock population decline of approximately 13 % from 2009 to 2013. Farmers (n?=?240) from 16 villages from five provinces were surveyed in mid-2015 to determine their baseline knowledge, attitude and practices (KAP) associated with cattle reproduction. In addition, 16 case studies from three of these provinces were conducted to provide a more detailed assessment of current cattle reproductive husbandry practices. In order to assess the reproductive impact of previously implemented interventions, an endpoint KAP survey and longitudinal health and husbandry study from three Cambodian provinces conducted between 2008 and 2013 were also analysed. Three multivariable prediction models (two KAP and one longitudinal) identified the following significant factors associated with the reproductive outcomes ‘number of calves born’ or probability that cows ‘gave birth’: target feeding (P?=?0.074), growing vegetables (P?=?0.005), attitudes towards cattle vaccination (P?=?0.010), improving bull selection (P?=?0.032), local breed use (P?=?0.005), number of joining attempts (P?<?0.001), discontinuation of animal draught practices (P?=?0.003) and retention of breeding animals (P?<?0.001). The identification of significant factors and interventions in this study has led to intervention recommendations that can potentially improve reproductive efficiency, combat the declining cattle population and improve smallholder capacity to supply to expanding regional meat demand in South-East Asia and China.     

Characterization of the village goat production systems in the rural communities of the Eastern Cape,KwaZulu-Natal,Limpopo and North West Provinces of South Africa

Expansion of goat improvement programs requires exploration of the factors that influence the production system and breeding initiatives. Characterization of goat breeds or populations is crucial in providing information on prevalent goat types and their attributes and may suffice as a guideline on conservation, development, and selection for improved productivity. This study investigated the existing village goat production system and phenotypic diversity of the different village populations from four South African provinces. The study further investigated the use of phenotypic attributes to classify goats to breeds or populations. Data was collected from 142 households in 26 villages of the Eastern Cape (n?=?2 villages), KwaZulu-Natal (n?=?6 villages), Limpopo (n?=?13 villages), and North West (n?=?5 villages) provinces through a survey. Individual interviews and focus group discussions revealed that the mean goat herd size per household was least in Limpopo at 13.2?±?12.40 and highest in Eastern Cape (34.18?±?28.36). Flocks had more (p?<?0.05) adults than kids, and the distribution of breeding animals was biased towards does and less bucks. Goats were kept mainly for meat, for selling, and for ritual ceremonies. The goat production system was mainly scavenging. Goat health was a major challenge across households and villages. Qualitative traits such coat, horn, ears, and wattle characteristics were recorded for populations of village goats (n?=?319) and a feral Tankwa breed (n?=?50). The dominant coat pattern was plain (74.53%) with black as the most common coat color (31.98%). Across breeds, a majority (88.08%) of the goats had horns, and 7.59% had wattles while 56.64% had beard. Adult goats (<3 years; n?=?398) were further analyzed for five quantitative traits of chest girth, height, length, and pin bone and there were significant (p?<?0.05) breed differences in all. A stepwise discriminatory procedure was used to rank the quantitative traits according to their discriminatory power to separate breeds or populations. Significant traits were then subjected to canonical discriminant analysis for principle component analysis. Based on the quantitative traits, the Tankwa, Xhosa, and Tswana goats formed their own cluster separated from commercial meat type breeds and the Venda and Zulu ecotypes. The discriminant function analysis correctly classified 90.41% of the Zulu goats and 82.93% of the Xhosa village populations. None of the Savanna goats were correctly classified. The study demonstrated diversity in village goat populations and production systems, which would allow for within population selection in genetic improvement programs. The heterogeneity in the phenotypic traits in the village goats is reflective of the role of village production systems in the maintenance of animal diversity in local populations.     

Effect of breeding method and season on pregnancy rate and embryonic and fetal losses in lactating Nili-Ravi buffaloes

The aim of this study was to determine the effect of breeding method and season on pregnancy rate and cumulative embryonic and fetal losses in Nili-Ravi buffalo. Estrus detection was performed twice a day by teaser buffalo bull for 1 hour each. A 2?×?2 factorial design was used to address the breeding method and season. Buffaloes (n?=?130) exhibiting estrus were randomly assigned to be bred either in peak breeding season (PBS; n?=?80) or low breeding season (LBS; n?=?50). Within each season, buffaloes were divided to receive either natural service (NS; n?=?65) or artificial insemination (AI; n?=?65). NS buffaloes, in estrus, were allowed to remain with the bull until mating. AI was achieved, using frozen thawed semen of bull of known fertility. PBS comprised of September to December and LBS were from May to July. Serial ultrasonography was performed on days 30, 45, 60, and 90 after breeding (day 0) to monitor pregnancy rate and embryonic and fetal losses. The pregnancy rate on day 30 after breeding was higher in NS as compared to AI group (63 vs. 43%; P?<?0.05) during PBS while it did not differ (48 vs. 32%; P?>?0.05) in LBS. The cumulative embryonic and fetal losses between days 31 and 90 were significantly lower in PBS than LBS (33 vs. 60%; P?<?0.05), ignoring breeding method. Pregnancy rates were better with NS in PBS, and cumulative embryonic fetal losses were higher in LBS in Nili-Ravi buffalo.     

A survey of rift valley fever and associated risk factors among the one-humped camel (<Emphasis Type="Italic">Camelus dromedaries</Emphasis>) in Sudan

Background

Rift valley fever (RVF) is a mosquito-borne viral disease of domestic livestock and wild ruminants. In camels RVF may cause abortion among pregnant camels, but is most often asymptomatic among other camels. In this study, a seroepidemiological survey was conducted to determine the prevalence of RVFV antibodies and to identify the potential risk factors associated with RVFV seropositivity among the Sudanese one-humped camel (Camelus dromedaries) in Khartoum State, Sudan. A cross sectional study was conducted in Khartoum State, Sudan, in a total of 240 camels selected randomly from four localities. Sera sampled were tested for the presence of RVFV-specific immunoglobulin G (IgG) antibodies using a competitive enzyme-linked immunosorbent assay (c-ELISA).

Results

RVFV seropositivity was recorded in 23 out of 240 animals, prevalence rate of 9.6 % among camels in Khartoum State. Age (OR?=?8.29, p-value?=?0.04) and heavy rainfall (OR?=?5.36, p value?=?0.01) were recorded as potential risk factors for contracting RVF.

Conclusions

Older age and heavy rainfall were considered as potential risk factors for seropositivity to RVF. Surveillance for RVF among camels and distribution of mosquito vectors should continue to better understand the clinical signs associated with RVFV infection in camels and provide public health authorities an opportunity to anticipate and prepare for a possible RVF outbreak in Khartoum State, Sudan.

     

Prevalence of <Emphasis Type="Italic">Haemonchus contortus</Emphasis> infection in sheep slaughtered at Jimma town municipal abattoir,Ethiopia

Haemonchus contortus is a parasite of major economic importance of most sheep-rearing areas of the world. A cross-sectional study was conducted from November 2015 to March 2016 with objectives of determining the prevalence and associated risk factors of Haemonchus contortus infection in sheep slaughtered at Jimma town municipal abattoir, Ethiopia. Of the total 7000 sheep slaughtered during the study time period, 384 sheep were randomly selected and examined for parasites. The overall prevalence of Haemonchus contortus infection was 264 (68.75%). Infection rate of poor body condition animals was significantly (P?=?0.000) higher than good body conditioned animals. The mean packed cell volume (PCV) values (%) of parasitemic and aparasitemic sheep were 23.73?±?3.7 SD and 37.66?±?4.736 SD, respectively. The prevalence in adult sheep (>?1 year) was insignificantly (P?=?0.653) higher than that of young sheep (≤?1 year). The highest prevalence was recorded in sheep that originated from Seka district (73.3%) and the lowest in Kersa district (63.4%) with non-significant variation (P?=?0.691). The highest monthly mean worm burdens and prevalence of Haemonchus contortus infection were recorded in November and lowest in March. The current study revealed that Haemonchus contortus infection is an important and common parasitic disease and requires special attention to its control.     

The use of melatonin and progestagen–eCG to initiate reproductive activity in prepuberal Awassi ewe lambs

This experiment was conducted to evaluate the effect of administering hormonal treatments (melatonin and progestagen/equine chronic gonadotropin (eCG)) on advancing puberty in Awassi ewe lambs. Fifty-one 6-month-old ewe lambs of similar body weights (around 28 kg) were randomly assigned into four treatment groups; control (CON; n?=?14), melatonin (MEL; n?=?13), melatonin plus progestagen–eCG (MELPP; n?=?11), and progestagen–eCG (PP; n?=?13). Ewe lambs in the PP and MELPP groups were fitted with intravaginal progestagen sponges containing 60 mg medroxyprogesterone acetate for 14 days; 400 IU eCG were administered to each of these ewe lambs on the day of sponge removal. Ewe lambs in the MEL and MELPP groups received subcutaneous melatonin implants (Regulin®, 18 mg melatonin) 36 days before sponge insertion. Hormonal treatment had no effect on ewe lamb body weight change. Estrous behavior was greater (p?p?p?p?相似文献   

Status of bovine tuberculosis and its zoonotic implications in Borana zone,Southern Ethiopia

A cross-sectional study was carried out from April 2015 to June 2016 to estimate the status of bovine tuberculosis (BTB), assessment of community’s current knowledge, and zoonotic importance on this disease in Borana zone, southern Ethiopia. In this study, comparative intradermal tuberculin (CIDT) test, structured questionnaires, and retrospective data were used, while the result indicated 3.8% prevalence at individual animal level with 5.6% (31/554) of doubtful reactors. Among related risk factors included, old animals were significantly infected by BTB than young one (χ ²?=?32.005, P?=?0.001). Parity number again showed significant difference (χ ²?=?29.163, P?=?0.001) where animals with many parity were more reactive to conducted test than few parity numbers. Animals born in the breeding center managed under semi-intensive production system were more infected (χ ²?=?10.795, P?=?0.029) than those brought from outside of the center. Questionnaire survey in this study indicated that out of 130 interviewed respondents, only 30% pastoralists knew what BTB mean; whereas the level of individual knowledge from interviewed showed about 72.3% of respondents had poor understanding of BTB and only about 11.5% of them knew its zoonotic importance. Meat eating habit of communities in the area were culturally inhabited to eat cooked meat and only 12.3% (16/130) of respondents gave response on habit of eating both raw and cooked meat. Milk drinking habit of pastoralist in the area showed about 79.2% drunk raw milk and the rest 20.8% used both raw and boiled milk. A retrospective data from Yabello Hospital indicated that current prevalence of human TB as 38.79% and showing the disease was highly increasing from year to year in the study area. This implies a great importance of human tuberculosis and its future concern in Borana zone. From this, there should be detail awareness of communities on BTB, its zoonotic importance, and the need of further investigation to develop control and prevention strategies according to the pastoral settings.     

Arterial pulse wave propagation velocity in healthy dogs by pulse wave Doppler ultrasound

The aim of this study was to prospectively evaluate the carotid-femoral pulse wave velocity (PWV) values in healthy dogs using pulse wave Doppler ultrasound. A secondary aim was to determine the feasibility of this method and to report the intra- and interobserver reproducibilities of the PWV in conscious dogs. The data were studied in 30 healthy, adult, male (n?=?15) and female (n?=?15) dogs. The time interval marked between the R wave peak of the electrocardiogram and the intersection of the blood flow wave upstroke of the Doppler spectrum with the baseline of zero frequency was determined for the carotid (T₁) and for the femoral (T₂) arteries. The distance covered by the pulse wave (L) was determined. The PWV was then calculated using the following formula: L/T₂ - T₁. The mean values of PWV calculated from the total sample (n?=?30) evaluated were 13.41?±?2.20 m/s. No significant statistical difference was observed for the PWV measurements between males (14.82?±?3.18 m/s) and females (12.64?±?2.45 m/s). The analysis revealed no intra nor interobserver differences. A reasonable reproducibility of the PWV measurements was showed by intraclass correlation coefficients (ICC), and the coefficients of variation (CV). These data demonstrate that noninvasive vascular Doppler analysis is a feasible and reproducible method to determine the carotid-femoral PWV in dogs.     

Expression of matrix metalloproteinase 2 (MMP-2), E-cadherin and Ki-67 in metastatic and non-metastatic canine mammary carcinomas

Background

The aim of the study was to demonstrate the immunohistochemical expression of proteins that affect the metastatic potential of a tumour, including matrix metalloproteinase 2 (MMP-2) and E-cadherin. Another objective was to determine their correlation with the expression of the Ki-67 antigen in metastasizing and non-metastasizing mammary carcinomas in female dogs. The study was conducted on 32 canine mammary carcinomas (12 metastatic and 20 non-metastatic), classified as simple tubular and tubulopapillary carcinomas. Immunohistochemistry was performed to evaluate the expression of MMP-2, E-cadherin and Ki-67 antigen.

Results

MMP-2 was expressed in 85 % of the non-metastatic tumours and in all the metastatic tumours, while E-cadherin was expressed in 85 % of the non-metastatic tumours and in 66 % of the metastatic tumours. The Ki-67 antigen was expressed in 65 % of the non-metastatic tumours and in 91 % of the metastatic tumours. The mean Ki-67 expression was slightly higher in tumours that had metastasized (1.5?±?0.90 vs 1.1?±?0.94; p?=?0.22). A similar relationship was found in terms of the intensity of the MMP-2 expression (2.9?±?1.9 vs 2.7?±?2.4; p?=?0.50). A decrease in the expression of E-cadherin (2.8?±?2.5) was found in metastatic tumours compared to the expression in non-metastatic tumours (3.2?±?2.3). However, these differences were not statistically significant (p?=?0.63).

Conclusion

We did not show significant differences in MMP-2, E-cadherin and Ki-67 expression between metastatic and non-metastatic tumours due to low number of cases studied, however further experiments are necessary to assess the role of these antigens in the process of canine mammary tumours metastasis.

     

Evaluation of transmission of bovine viral diarrhea virus (BVDV) between persistently infected and naive cattle by the horn fly <Emphasis Type="Italic">(Haematobia irritans)</Emphasis>

Identifying reservoirs and transmission routes for bovine viral diarrhea virus (BVDV) are important in developing biosecurity programs. The aim of this study was to evaluate BVDV transmission by the hematophagous horn fly (Haematobia irritans). Flies collected from four persistently infected cattle were placed in fly cages attached to principal (n?=?4) and control (n?=?4) BVDV-naïve calves housed individually in isolation rooms. Flies were able to feed on principal calves, but a barrier prevented fly feeding from control calves. Flies were tested for BVDV by RT-PCR and virus isolation at time of collection from PI cattle and after 48 h of exposure on BVDV-naïve calves. Blood samples were collected from calves and tested for BVDV infection. Virus was isolated from fly homogenates at collection from PI animals and at removal from control and principal calves. All calves remained negative for BVDV by virus isolation and serology throughout the study. Bovine viral diarrhea virus may be detected in horn flies collected from PI cattle, but horn flies do not appear to be an important vector for BVDV transmission.     

The effect of post-mating hCG or progesterone administration on reproductive performance of Afshari × Booroola-Merino crossbred ewes

To investigate the efficiency of hCG/CIDR after breeding to increase the reproductive performance, 35 synchronized ewes were mated with fertile rams and were assigned to three treatment groups. Ewes in hCG group (n?=?12) received 400 IU hCG on day 11 post-mating, and ewes in CIDR group (n?=?11) received CIDR from day 7 until day 19 post-mating. Ewes in the control group (n?=?12) did not receive any treatment. Blood samples were collected on days 7, 12, 17, and 22 post-mating. Plasma P₄ concentrations were higher on days 12 and 17 post-mating in hCG- and CIDR-treated groups (P?<?0.05). However, the concentrations of P₄ on day 22 post-mating in hCG and control groups were higher than that in CIDR group (P?<?0.05). Ewes in hCG group produced more quadruplets (P?<?0.05) and triplets, and as a result, they had a larger litter size (P?<?0.05). The lamb mortality rate by weaning in hCG group (3.6%) was less than that in control (11.8%; P?<?0.05) and CIDR (9.1%; P?>?0.05) groups. Post-mating administration of hCG or CIDR did not affect the lamb birth weight in single and quadruplet births (P?>?0.05), but the birth weight of twin lambs was higher in the hCG and CIDR groups (P?<?0.05). Weaning weights of twin lambs were higher in the hCG and CIDR groups (P?<?0.05). In conclusion, hCG/CIDR administration post-mating increased the maternal P₄ concentrations and enhanced reproductive performance.     

A comparison of the efficacy of subcutaneously administered ivermectin,doramectin, and moxidectin against naturally infected <Emphasis Type="Italic">Toxocara vitulorum</Emphasis> in calves

This study was conducted to investigate the efficacy of ivermectin (IVM), doramectin (DRM), and moxidectin (MXD) against Toxocara vitulorum in calves. In the study, 20 calves naturally infected with T. vitulorum were divided into four groups: three different treatment groups (n?=?5) and one positive control (n?=?5). The animals in each group received either IVM (Baymec®, Bayer), DRM (Dectomax®, Pfizer), or MXD (Cydectin®, Fort Dodge) by subcutaneous injection at a single dose of 0.2 mg/kg. Fecal egg counts were performed on all animals on days 0, 2, 4, 8, 12, and 16 post-treatment. In conclusion, IVM, DRM, and MXD significantly reduced the fecal egg counts on day 8 post-treatment (99.90%, 98.77%, and 99.57%, respectively). After the 12th day, IVM, DRM, and MXD were found to be 100% effective. There was no significant difference in efficacy between the three treatment groups at any of the sampling dates (P?>?0.05). No side effects associated with nervous, respiratory, and gastrointestinal systems were observed. This is the first study to evaluate the comparative efficacy of subcutaneous administration of ivermectin, doramectin, and moxidectin against naturally infected T. vitulorum in calves.