Association of precalving serum NEFA concentrations with postpartum diseases and reproductive performance in multiparous Holstein cows: Cut-off values.

BACKGROUND: High concentrations of NEFA relative to a defined reference or 'cut-point' values before calving can predict the risk of specific or collective periparturient disease events. OBJECTIVES: A field-based cohort study was conducted to evaluate the value and critical points of serum nonesterified fatty acids (NEFA) at the precalving time to predict the occurrence of postpartum diseases and reproductive performance in dairy cows. METHODS: Blood samples were taken from 521 high-yielding dairy cows at 1 week (±3 days) before calving and NEFA levels were measured. Health and reproduction information of each cow includes dystocia, retained placenta, milk fever, metritis, mastitis, pregnancy in the first insemination and pregnancy in the first two inseminations, and culling in the first 60 days of lactation and milk production. RESULTS: Our results show that there are significant relationships between precalving NEFA with the probability of pregnancy at the first and the first two inseminations after calving. The cows that had NEFA concentrations less than 0.5 mmol/L at the last week of pregnancy were 3.51 and 3.15 times more likely to be pregnant at first insemination and the first two inseminations, respectively. Also, our results showed that there are significant relationships between precalving NEFA concentration and the likelihood of dystocia and milk fever. The probability of dystocia and milk fever occurrence were 2.56 and 1.91 times greater in those cows that had NEFA concentrations more than 0.3 mmol/L, respectively. CONCLUSIONS: The present results indicated that Increasing NEFA during the prepartum period could adversely affect the reproductive efficiency of dairy cows.

Variations of some adipokines, pro-inflammatory cytokines, oxidative stress biomarkers, and energy characteristics during the transition period in dairy cows.

Limited information exists about the relationship of adipose tissue with inflammation, oxidative stress, and energy metabolism during the transition period in dairy cows. The objective of this study was to assess the changes and relation of some adipokines, cytokines, oxidative biomarkers, and serum biochemical parameters related to energy balance (EB) in cows during the transition period. Thirty multiparous Holstein cows were selected based on estimated parturition date, and blood samples were collected from jugular vein on one-week prepartum and one and three weeks postpartum and used to measure the parameters. The serum levels of beta-hydroxybutyric acid (BHB), non-esterified fatty acid, cholesterol, high-density lipoprotein (HDL), aspartate aminotransferase, and total antioxidant capacity increased significantly, and glucose, urea, triglyceride (TG), and low-density lipoprotein (LDL) decreased significantly after parturition. The serum values of adiponectin, resistin, leptin, and cytokines including interleukin 6 (IL-6) and tumor necrosis factor (TNF)-α were not changed significantly during the experiment. The results of the Pearson correlation revealed a significant negative correlation between BHB with glucose, albumin, cholesterol, HDL, LDL, and a positive correlation with TG and malondialdehyde. Also, there was a significant direct correlation between insulin and leptin, adiponectin, resistin, IL-6 and TNF-α in the whole experiment period. These emphasize the difficulty of dairy cows to manage the energy requirements during the transition period. It can be stated that adipokines and cytokines may have an essential role in the metabolic status in this period, and control of their production and, or secretion could be helpful in EB during the transition period.

Correlations of whole blood heavy metals with serum immunological and oxidative markers during the early dry period and transition period of dairy cattle.

Immunological and oxidative alterations have been reported around calving in dairy cattle. In addition, the levels of heavy metals rise in the blood around parturition, which might affect body systems. Therefore, in this Research Communication we evaluate the changes in whole blood lead (Pb), arsenic (As), and cadmium (Cd) around calving, in comparison with the beginning of the dry period, and assess the correlations of these elements with immunological factors and oxidative markers. Samples were collected from 30 clinically healthy dairy cows in the early dry period (-6 w), one week before expected calving (-1 w), and one week postpartum (+1 w). The highest concentrations of Pb, As, and Cd were observed at -1 w and all the three elements decreased after parturition leading to significantly lower As and Cd, compared to -1 w (P < 0.05). The lowest levels of tumor necrosis factor-alpha, immunoglobulin G, interleukin 4, interleukin 10 and haptoglobin were found at -1 w simultaneous with the highest measures of the heavy metals, with tumor necrosis factor-alpha being significantly lower at this time (P < 0.05). At -6 w, As concentration was significantly (P < 0.05) correlated negatively (r = -0.366) and positively (r = 0.417) with total antioxidant capacity and malondialdehyde, respectively. Furthermore, at -1 w Pb and As had significant (P < 0.05) negative correlations with interferon gamma (r = -0.502) and interleukin 4 (r = -0.483), respectively. After parturition, Pb was observed to be negatively correlated with total antioxidant capacity (r = -0.538, P < 0.05). The observed results revealed that the alterations in immunological factors and antioxidant capacity around parturition were correlated with Pb and As levels.

Effects of vitamin D3 injection in close-up period on insulin resistance and energy balance in transition dairy cows.

BACKGROUND: Many studies in dairy cows are towards calcium homeostasis and there is a lack of knowledge about the effect of vitamin D in preventing insulin resistance and improving energy balance in the transition period of dairy cows. METHODS: The trial was conducted in a commercial dairy farm with about 1500 lactating cows in Tehran province, Iran. Twenty-four Holstein cows had been randomly selected and divided into control and treatment groups. In the treatment group, 12 cows, received a single dose of 8,000,000 IU vitamin D3 intramuscularly and in the control group, 12 cows were injected placebo (distilled water) 2-8 days before the expected calving time. Blood samples were collected between 8 and 10 AM 2 h after feeding on 21 and 7 days before calving and 1,3,7,15 and 30 days after calving. 25(OH)vitamin D, insulin-like growth factor 1 (IGF-1), insulin, nonesterified fatty acid (NEFA), ß-hydroxybutyric acid (BHBA), albumin, total protein, glucose, urea, triglyceride, cholesterol and aspartate amino transferase (AST) were measured by commercially available kits. The insulin resistance index was calculated. RESULTS: Vitamin D3 injection significantly affected the amounts of 25(OH) vitamin D, urea, insulin and insulin resistance index (p ≤ 0.05). On the other hand, the amounts of glucose, NEFA, BHBA concentration and AST activity were higher in control group (p ≤ 0.05). Time had a significant effect on the amounts of most measured variables except IGF-1 and insulin. There were no group and time interactions for measured variables. CONCLUSION: It seems that injection of vitamin D3 in close up period influenced lipolysis potentially modifying energy metabolism and resulted in reducing insulin resistance.

Comparison of the effects of tylosin and tilmicosin as a systemic treatment of dry Holstein cows.

The aim of the present study was to evaluate the efficacy of macrolides to eliminate intramammary infection (IMI) caused by Staphylococcus aureus (S. aureus) and Streptoccus spp. 3 weeks before calving time. Eighty Holstein dairy cows with subclinical mastitis pathogens were divided into three groups. Three weeks before expected parturition time, cows in group 1 received tilmicosin (n = 29), cows in group 2 received tylosin (n = 30) and cows in group 3 were left as negative control (n = 21). Milk samples were obtained on 3 and 7 days after calving. Randomly amplified polymorphic DNA (RAPD) method was determined for all of the S. aureus isolates that had the same isolates before and after parturition. The total cure rate was 63.33, 75.86 and 66.66% for tylosin, tilmicosin and control groups, respectively. Furthermore, cure rates were not significant, when each type of mastitis causing pathogens were considered separately. The incidence of clinical mastitis during 60 days after calving for tylosin, tilmicosin and Control groups was 23.33, 27.58 and 38.09%, respectively. Only four S. aureus isolated before drying-off were similar to post-calving isolate, according to RAPD-PCR method. In conclusion, antibiotic therapy before calving improved the cure rate numerically, however, it was not significant.

Addition of straw to the early-lactation diet: Effects on feed intake, milk yield, and subclinical ketosis in Holstein cows.

This study evaluated feed intake, milk yield, and subclinical ketosis in dairy cows in early lactation fed 2 different diets postpartum. Cows are typically offered a high-energy ration immediately after calving. We compared a conventional high-energy total mixed ration (TMR) with a transition ration that contained chopped straw. We predicted that adding chopped straw would increase dry matter intake, milk production, and indicators of energy metabolism during the first 3 wk of lactation compared to cows fed a conventional high-energy TMR. We also predicted that carryover effects would be likely for at least 2 wk after treatment ended. A total of 68 mixed-age Holstein cows were enrolled in the study 3 wk before their expected calving. All cows were managed on a single high-forage diet during the dry period. At calving, cows were allocated to 1 of the 2 diets: half to the conventional high-energy TMR (CTMR; n = 34; net energy for lactation = 1.61 Mcal/kg; neutral detergent fiber = 31.7%), and the other half to a high-forage TMR containing chopped wheat straw, equivalent to 4.27% dry matter (STMR; n = 34; net energy for lactation = 1.59 Mcal/kg; neutral detergent fiber = 33.7%) for 3 wk after calving. Cows on STMR were then shifted to CTMR for the next 2 wk to study short-term residual effects on the performance of cows. Treatments were balanced for parity, body condition score, and body weight. Feed intake was measured daily from 2 wk before to 5 wk after calving using automatic feed bins. Blood was sampled twice weekly from 2 wk before to 5 wk after calving, and ß-hydroxybutyrate and glucose were measured in serum samples. Subclinical ketosis was identified using a threshold of ß-hydroxybutyrate ≥1.0 mmol/L in wk 1 after calving and ≥1.2 mmol/L in wk 2 to 5 after calving. Cows were milked twice daily, and weekly samples (composite samples of morning and afternoon milkings) were analyzed to determine total solids, fat, protein, lactose, and somatic cell count. Data were analyzed in 2 separate periods: the treatment phase (wk +1, +2, and +3) and the post-treatment phase (wk +4 and +5). The addition of straw to the TMR negatively affected the dry matter intake of STMR cows during wk 2 and 3 of lactation. Daily milk yield during the first 5 wk of lactation was lower in STMR cows than in CTMR cows. Concentrations of ß-hydroxybutyrate were higher in CTMR cows than in STMR cows during wk 1, but this effect was reversed during wk 2 and 3 of lactation. By 21 d in milk, STMR cows had a greater risk of developing subclinical ketosis than CTMR cows. Adding chopped wheat straw to the TMR during the first 21 d after calving lowered dry matter intake and provided no metabolic or production benefits to lactating dairy cattle.

Supplementation of overripe pulp extract and green peel extract or powder of banana fruit peel (musa. cavendish) to diets of neonatal dairy calves: Effects on haematological, immunological and performance characteristics.

The present study investigated the effects of overripe pulp and green peel extract and powder of banana fruit (Musa. cavendish) on haematological, biochemical, immunological, health, and performance of Holstein dairy calves. In all, 40 newborn calves were randomly divided into four groups of 10 animals. In the control group, animals received no banana meal. In group 1, calves were supplemented with 2 g (dry matter)/kg body weight/day of overripe banana pulp extract. The calves in group 2 were supplemented with 1 g (dry matter) of overripe banana pulp extract/kg body weight/day and 1 g (dry matter) of green banana peel extract/kg body weight/day. The animals in group 3 were supplemented with 2 g/kg body weight/day of green banana peel powder. The feeding period of calves on the tested supplements was 5 days. Blood samples and other evaluations were taken on day 0 (at birth, before supplementation) and on days 7, 15 and 30. Just a trend towards better average daily weight gain was seen in groups 2 and 3 than others (p = 0.073). Significant group and sampling time interactions were seen for the quantities of RBC (group 1 was lower than other groups at day 30), MCV (group 3 was lower than other groups at day 30) and MCH (group 1 was higher than other groups at day 30) (p < 0.05). A trend towards significance in values of IgG (group 1 was lower than other groups at days 15 and 30) and bilirubin (higher values at day 7 in groups 1 and 2 than control, higher amounts at days 15 and 30 in groups 3 and 2 than control, respectively) was also observed. In conclusion, banana supplementation in neonatal calves had beneficial effects on the values of RBC, MCV, MCH, bilirubin, IgG and average daily weight gain in dairy calves.

The Effects of Parenteral Iron Administration on Thyroid Hormones, Hematology, Oxidative Stress Characteristics, Performance, and Health in Neonatal Holstein Calves.

The present study investigated the effect of iron supplementation on thyroid hormones concentrations, oxidative stress characteristics, complete blood count (CBC) and serum biochemistry, and performance and health in calves of two groups: test group (n = 17, intramuscular injection of 500 mg iron-dextran on the 2nd day of life) and control group (n = 17, intramuscular injection of normal saline at the same time). Blood samples were taken from all of the calves instantly after birth and at 7, 14, 21, 28, and 90 days of age. Duration of treatment for diseases, body weight, height, and length were measured at each sampling time to evaluate growth and health. The results indicated that age (sampling time) had a significant effect (p ≤ 0.05) on the values of all measured variables except for ferric reducing ability of plasma (FRAP) amount and band neutrophil number. The treatment (group) had no significant effect on the amount of measured variables. Significant interactions between sampling time and group were found for white blood cell count (WBC), adult neutrophil, and bilirubin amounts (p ≤ 0.05). Significant higher amounts of hematocrit (HCT) and hemoglobin (Hb) at day 28 and mean corpuscular volume (MCV) at day 7 were seen in the test group compared with control group. Test group in comparison with control group had significantly lower amount of WBC at day 7; mean corpuscular hemoglobin concentration (MCHC), band neutrophils, and lymphocytes at day 14; and number of platelets at day 28. Growth and total weight gain and mean daily gain had no significant differences between the two groups. The duration of treatment for pneumonia and diarrhea was not significantly different between trial groups. The results show that parenterally administration of iron to newborn calves had no effect on improving erythropoiesis, performance, thyroid metabolism, oxidative/antioxidative situation, and health of dairy calves.

Effect of prostaglandin F2α and GnRH administration at the time of artificial insemination on reproductive performance of dairy cows.

The present study aimed to determine the effect of administrating prostaglandin F2α (PGF2α) and GnRH at the time of artificial insemination (AI) on the pregnancy per artificial insemination (P/AI) and the pregnancy survival rate of dairy cows. A number of 830 lactating Holstein cows were randomly divided into four groups. Cows in group 1 (n=200) treated with 150 µg d-cloprostenol. In group 2 (n=212), cows received 10 µg buserelin acetate, and group 3 (n=205) was treated with both 150 µg d-cloprostenol and 10 µg buserelin acetate. In addition, 213 cows were assigned as control group which received normal saline as placebo (group 4). To measure progesterone, milk samples were collected at the insemination day and five days later. Pregnancy diagnosis was performed 28 and 60 days after the insemination, and the size and number of corpus luteum (CL) and twin pregnancies were recorded. Hormone therapies had no effect on the P/AI, pregnancy survival rate, and the size and number of CL. The P/AI ratio in groups 1, 2, 3 and 4 were 38.50%, 42.92%, 41.46% and 40.84%, and the pregnancy survival rates in groups 1, 2, 3 and 4 were 84.42%, 86.81%, 88.23% and 83.91%, respectively. The probability of a twin pregnancy was significantly higher in group 1 (15.58%) than other groups. There was no significant difference between groups in terms of the offspring gender. In conclusion, the administration of d-cloprostenol or buserelin acetate at the time of AI had no effect on P/AI and pregnancy survival rate in dairy cattle under no heat stress condition, while the administration of d-cloprostenol increased the probability of twin pregnancies.

Effects of Dexamethasone and Insulin Alone or in Combination on Energy and Protein Metabolism Indicators and Milk Production in Dairy Cows in Early Lactation - A Randomized Controlled Trial.

OBJECTIVES: This study investigated the effects of dexamethasone and insulin, when administered at 3rd or 10th day of lactation on energy and protein metabolism in dairy cows. MATERIALS AND METHODS: Two hundred Holstein cows were enrolled in a randomized controlled clinical trial. The cows were randomly assigned to receive 1 of 4 treatments at 3 or 10 days in milk: control group, 10-mL i.m. injection of sterile water, group insulin, s.c. injection of 100 units of insulin, group dexamethasone, i.m. injection of 20 mg of dexamethasone, group insulin plus dexamethasone, i.m. injection of 20 mg of dexamethasone and 100 units of insulin. The cows randomly assigned to receive the treatments on 3 or 10 days of lactation. Serum samples obtained at the time of enrollment, time of treatment and at 2, 4, 7 and 14 days after intervention. The sera were analyzed for ß-hydroxybutyrate (BHBA), nonesterified fatty acids (NEFA), glucose, cholesterol, albumin, urea, and aspartate amino transferase (AST). Data were analyzed using a repeated measures mixed model that accounted for the effects of parity, body condition score, dystocia, retained placenta, metritis and the random effect of cow. RESULTS: There was no significant interaction of group of treatment and time of intervention (day 3 or 10 post-partum) on serum components. Cows that received insulin or dexamethasone alone or in combination, had lower BHBA 2 days after treatment compared with control cows, whereas concentrations of NEFA, were unaffected suggesting that glucocorticoids lipolytic effects do not appear to be important in healthy cows. AST activities significantly reduced in cows that received dexamethasone with or without insulin at 2 and 4 days after treatment. Albumin and urea concentrations 2 days after treatment were higher for cows that received dexamethasone only or dexamethasone plus insulin compared with control and Ins received cows. There were no treatment effects on test-day milk production, milk fat and protein percentages. CONCLUSIONS: The results suggested that administration of glucocorticoids in early lactation resulted in short-term improvement of metabolism in postpartum dairy cows in biochemical terms.

Treatment of clinical endometritis in dairy cows by previously used controlled internal drug release devices.

Postpartum endometritis is considered as one of the diseases that lead to a potential profit reduction in dairy cows. The aims of the present study were to promote follicle growth by a previously used controlled internal drug release (CIDR) device and to evaluate its effect on the likelihood of recovery and the reproductive performance of clinical endometritis (CE) cows. Endometritis was diagnosed using ultrasonographic examination at 31 ± 3 (Day 0 of the experiment) days in milk, and CE cows were included in one of the three experimental groups according to the presence of a CL on their ovaries. Cows without CL on their ovaries received a reused CIDR device, which was previously used for 14 days (CIDR-14, n = 108), or PGF2α (PG-1, n = 112) on Day 0. In the third group, those with CL on their ovaries received PGF2α (PG-2, n = 107) at the same time. Ovarian structures, serum estradiol and progesterone concentrations were measured on Days 0, 7, and 14. Controlled internal drug release devices were removed, and response to treatment was evaluated in all treated cows on Day 14. Diameters of ovarian follicles were 11.61 ± 0.50, 12.46 ± 0.25, and 18.36 ± 0.60 mm on Day 7 and 11.63 ± 0.58, 14.35 ± 0.40, and 21.96 ± 0.77 mm on Day 14 in PG-1, PG-2, and CIDR-14 cows, respectively (P < 0.05). Serum estradiol concentrations were higher in CIDR-14 cows (141.17 ± 1.04 pg/mL) than in PG-1 (116.85 ± 1.05 pg/mL) and PG-2 (119.10 ± 1.05 pg/mL) cows on Day 7 (P < 0.05). Higher progesterone concentrations were observed in PG-2 cows than in PG-1 and CIDR-14 cows on Days 0, 7, and 14 (P < 0.001). The likelihood of clinical cure was 54.46%, 62.61%, and 64.81% in PG-1, PG-2, and CIDR-14 cows, respectively (P = 0.11). First-service conception risk, days to the first service, calving to conception interval, proportion of cows bred and pregnant by 120 days in milk did not differ among the treated groups (P > 0.05). The cumulative pregnancy risk was lower in PG-1 (77.67%) cows than in CIDR-14 (87.07%) and PG-2 (87.85%) cows (P = 0.02). In conclusion, reused CIDR would be contributed to the treatment of CE by promotion of follicle growth and induction of sustainable sources of endogenic estrogen secreted by the dominant follicle.

Molecular and serological detection of Theileria equi and Babesia caballi infection in horses and ixodid ticks in Iran.

Equine piroplasmosis is a hemoprotozoan tick-borne disease with worldwide distribution that is caused by Theileria equi and Babesia caballi. However, the geographical distribution of equine piroplasmosis in Iran is unknown. The aim of the current study was to determine the causative agents and vector ticks of equine piroplasmosis in horses in the North Khorasan Province. In the year 2011, 100 horses were randomly selected from 14 villages. Blood samples and ixodid ticks were collected and examined using microscopical, molecular, and serological methods. Theileria equi infection was microscopically detected in 5 (5%) of the blood smears with low parasitemia, while serum samples were tested by the indirect immunofluorescent antibody test (IFAT). Antibodies against T. equi, B. caballi, and a mixed infection were detected in 48 (48%), 2 (2%), and 3 (3%) of the serum samples, respectively. A multiplex PCR was used to detect T. equi and B. caballi DNA in blood samples. No B. caballi infections could be found, but Theileria equi DNA was detected in 45 (45%) of the blood samples, and a BLAST analysis of the sequenced samples indicated a 99% similarity with T. equi 18S rRNA gene sequences in GenBank. Both molecular and serological results did not identify any significant association between T. equi infection and risk factors. A comparision of the results of 3 diagnostic methods demonstrated a poor agreement between microscopical examination with IFAT and PCR and a moderate agreement between IFAT and PCR. Thirty-seven adult ticks (20 females and 17 males) were collected from 15 horses. The most common tick was Hyalomma marginatum marginatum (n=19), followed by Hyalomma anatolicum excavatum (n=10), Rhipicephalus bursa (n=4), Hyalomma marginatum turanicum (n=3), and Hyalomma anatolicum anatolicum (n=1). The salivary glands and ovaries were also examined using PCR. The genomic DNA samples of the salivary glands of 3 ticks, H. a. excavatum (n=2) and R. bursa (n=1), had a positive reaction for T. equi, but no tick contained B. caballi DNA. Thus, our results indicate that T. equi occurs more frequently than B. caballi in the investigated geographical region.

Bovine salmonellosis in northeast of Iran: frequency, genetic fingerprinting and antimicrobial resistance patterns of Salmonella spp.

OBJECTIVE: To evaluate serovar and antimicrobial resistance patterns of Salmonella spp isolated from healthy, diseased and necropsied cows and calves in this observational study. METHODS: Nineteen isolates recovered from feces and tissues of salmonellosis-affected animals of two commercial farms in north-east of Iran. In second part of the study, the two farms were sampled 4 times with an interval of 2 month. The samples included calves' feces, adult cows' feces, feeds, water, milk filters, and milk fed to calves. Five Salmonella were isolated from 332 fecal samples collected from calves and peri-parturient cows. No Salmonella was recovered from water, feed, milk filers and milk fed to calves. RESULTS: Salmonella Typhimurium was the most frequently isolate among all sero-groups. S. Dublin was only accounted for 8% (two out of 24) of isolates. Isolated Salmonella strains were used for the ERIC PCR DNA fingerprinting assay. Our results grouped Salmonella isolates into 3 clusters, suggesting that specific genotypes were responsible for each sero-group of Salmonella. The results also revealed diversity among Salmonella isolates in cluster III (sero-group B). Eighteen out of 19 Salmonella spp. were resistant to oxytetracycline. Five isolates out of 19 showed more than one drug resistance. Multi-drug resistance was seen only among Salmonella Typhimurium isolates. Enrofloxacin was the most susceptible antibiotic against all isolates in this study. CONCLUSION: The emergence of multiple antibiotic-resistant strains of Salmonella Typhimurium should be of great concern to the public. No correlation between ERIC fingerprinting and resistance patterns of Salmonella isolates was found, which indicates resistance to antimicrobial agents was not related to specific genetic background.

Seroepidemiologic Survey of Canine Visceral Leishmaniasis in Tehran and Alborz Provinces of Iran.

BACKGROUND: A two year seroepidemiological study was designed to find out the seroprevalence and risk factors of canine visceral leishmaniasis (CVL) among stray and owned dogs in Tehran and Alborz Provinces of Iran. METHODS: Blood samples of 602 dogs living in 11 counties of Tehran and Alborz Provinces were taken by venipuncture in 2008-2010. After separation of blood sera, anti-leishmanial antibodies were detected by direct agglutination test (DAT). RESULTS: Overall, of the 408 and 194 serum samples collected randomly from dogs in 11 localities in Tehran and Alborz Provinces, 18/408 (4.41%) and 12/194 (6.18%) respectively were found positive. Among the localities, Shemiran in Tehran Province and Karaj In Alborz Province had the highest prevalence rates. No statistically significant differences were found between sex and living place but there was significant difference between living status (owned or stray) and CVL infection of dogs in Alborz Province (P= 0.018). The highest seroprevalence (7.5%) was found in dogs aged 3 to 5 years old. Only 20% of the seropositive dogs were symptomatic. CONCLUSION: Concerning possible human infections in Tehran and Alborz Provinces, both symptomatic and asymptomatic seropositive dogs should be considered as a risk.

Evaluation of copper concentration in subclinical cases of white muscle disease and its relationship with cardiac troponin I.

The present study aims to evaluate the serum level of copper (Cu) in lambs suffering from subclinical forms of white muscle disease (WMD) and its relationship with cardiac troponin I (cTn-I) as a novel biomarker of cardiovascular disorders. Ten milliliters of jugular blood were taken from 200 lambs less than one year old to measure serum concentrations of Cu, selenium (Se), and cTn-I. The subjects were divided into 2 groups, namely, the deficient group which included 36 lambs, and the control group which included 164 lambs according to the reference serum Se concentration (50 ng/mL). Serum Se levels in the deficient group were lower than 50 ng/mL. By contrast, the control group showed Se levels higher than 50 ng/mL. Differences among the serum Cu and cTn-I levels were determined in both groups. The mean ±SD and median of serum Cu and cTn-I levels in the deficient group were lower and higher than those in the control group, respectively. A significant positive correlation was observed between serum Cu and Se levels, and also serum Cu and Se levels showed a negative correlation with serum cTn-I concentrations. Stepwise linear regression analysis showed that serum Cu levels were correlated positively with serum Se levels (p<0.05). Receiver operating characteristic (ROC) curve analysis indicated that the area under curve (AUC) of Cu was significantly higher than that of cTn-I based on the reference diagonal line. It is important to keep in mind that the value of AUC for the ROC curve is between 0.5 and 1.00, in which the lowest accuracy is related to the reference diagonal line with AUC of 0.5. A cut-off was determined to indicate which Cu level can discriminate between affected and healthy lambs. The cut-off level, sensitivity, and specificity of Cu in this study were 144.5 ng/mL, 74%, and 61%, respectively.

Effects of monensin on metabolism and production in dairy saanen goats in periparturient period.

This trial evaluated the effects of dietary supplementation with monensin sodium on dry matter intake, metabolic parameters and milk yield and milk composition of dairy Saanen goats in the periparturient period. Twelve Saanen pregnant dairy goats were assigned to a treatment and a control group. Saanen goats were fed monensin as its 10% sodium salt in the amount of 33 mg/kg of total dry matter intake during 30 d before parturition till d 42 in milk. Blood samples were collected from each goat at d 30, 15 and 7 before expected kidding time and also in d 1, 7, 13, 19, 21, 28, 35 and 42 postpartum. The serum concentrations of ß-Hydroxybutyrate (BHBA), non-esterifed fatty acid (NEFA), calcium, magnesium, inorganic phosphorus, cholesterol, triglyceride, urea, total protein, albumin and glucose and aspartate aminotransferase (AST) activity were determined. The BHBA concentration significantly decreased in goats, which received monensin in comparison to controls in the postpartum period (p = 0.049). The concentration of sodium (Na) was significantly influenced by monensin treatment in the postpartum period (p = 0.048). In addition, the difference in dry matter intake was highly significant between the two groups during the pre-partum period. Controls had more dry matter intake (DMI) than treatment goats (p = 0.0001). Mean 3.5% fat corrected milk production was not influenced by monensin treatment. However, milk fat percentage was significantly decreased in monensin treated goats (p = 0.0017).

Effect of copper edetate injection in dry pregnant cows on hematology, blood metabolites, weight gain and health of calves.

The objectives of the present study was to investigate the effects of the copper injection and injection timing to pregnant dairy cows at dry period on the hematology, some serum metabolites, health and growth of their calves. Thirty Holstein cows at the dry period were assigned to the three following experimental groups: 1) control (injections of 2.5 ml normal saline), 2) test 1 (125 mg Cu as copper edetate injection at the first week of the dry period) and 3) test 2 (125 mg Cu as copper edetate injection at the third week of the dry period). Ten milliliters of jugular blood was taken from all calves 24-48 h after birth and at 7, 14, 21 and 28 days of age for measuring hematological and biochemical parameters. For evaluation of growth and health, body weight of all of the calves was measured at birth and at the end of the trial, and the health of calves was checked by a technician twice a day and any sign of illness, treatment (if needed) and duration of illness was recorded. Copper treatment was proved to have a significant effect on the counts of WBC (lower in test 2, higher in test 1), lymphocyte (lower in test 2, higher in test 1) and the concentrations of fibrinogen (lower in test 1, higher in test 2), cholesterol (lower in control, higher in test 1) and copper (lower in test 1, higher in test 2) (p < 0.05). Age (sampling time) also influenced most measured parameters (p < 0.05) except values of WBC, neutrophil, monocyte, globulin and concentrations of iron, zinc and copper.

Efficacy of conventional and extended intra-mammary treatment of persistent sub-clinical mastitis with cefquinome in lactating dairy cows.

The objectives of the present study were to evaluate the efficacy of intra-mammary-administered cefquinome for the treatment of sub-clinical mastitis in lactating dairy cows and to determine if extended therapy would enhance treatment efficacy. Seventy-three Holstein dairy cows from a single farm with 150 infected quarters were enrolled in the study. Infected cows were allocated randomly to one of three treatment regimens: (1) conventional (standard) regimen: 75 mg of cefquinome administered three times at 16-h intervals (25 infected cows, 52 intra-mammary infections (IMI)), (2) extended regimen: 75 mg of cefquinome administered six times at 16-h intervals (26 infected cows, 58 IMI) and (3) negative untreated control group (22 cows, 40 IMI). Most IMI were caused by coagulase-negative staphylococci, streptococci other than Streptococcus agalactiae and coliforms. The overall bacteriological cure (BC) rates for sub-clinical IMI were 84.61%, 91.37% and 20% for the conventional, extended and the control groups, respectively, indicating a higher BC rate for the treated groups than the control group (P < 0.001). Significant differences in somatic cell count (SCC) were detected between the treated versus the control group (P < 0.001). No differences, concerning the BC rate or SCC, were observed between the extended and the conventional groups. Although fat and protein percentages increased in the treated groups, there were no significant differences in post-treatment milk production between the groups. Results of this study indicate that cefquinome therapy was effective in reducing SCC and eliminating sub-clinical IMI in lactating dairy cows, but extended therapy did not enhance treatment efficacy.

Parenteral selenium and vitamin E supplementation to lambs: hematology, serum biochemistry, performance, and relationship with other trace elements.

Most regions in Iran are generally selenium (Se) deficient and all mineral premixes which used in farm animals contain Se in the form of sodium selenite. The objective of this study was to evaluate the effects of injected Se and vitamin E (vit E) on hematology, serum proteins, and performance of lambs during the period which the animals are at risk of Se and/or vit E deficiency. The study also aims to determine the relationship between selenium injection and the levels of other trace elements in blood serum of lambs. A total of 16 lambs of Baloochi breed (age, 70 ± 7 days and weight, 15.2 ± 1.4) were enrolled in the study. The animals were divided into two groups. In the test group, vit E and Se injected at a dose of 0.2 ml/kg BW (Vetoquinol, Selepherol®, Lure Cedex, France, α-tocopherol acetate 3.82 g/100 ml plus sodium selenite 0.023 g/100 ml) at the enrollment. Control lambs were received equal amounts of normal saline as placebo. Blood was sampled from the jugular vein at the beginning of the study (enrollment, before injection of vit E and selenium and saline) and at days 7, 14, 21, and 28 of experiment. The amounts of total serum protein, albumin, glucose, iron, copper, zinc, creatine kinase (CK), and aspartate aminotransferase (AST) and Se were measured. The concentration of globulin was calculated as the difference between total serum protein and albumin. For evaluation of growth and health, body weight of all the lambs was measured at day 0 of the experiment and the sampling times and days of treatment for each lamb were recorded. Treatment with Se and vit E decreased the activities of CK and AST compared to the controls (p < 0.05). Age (sampling time) had significant effects on the values of Se, iron, zinc, AST, hemoglobin, total protein, glucose, weight, height, and length (p < 0.05). Significant interactions between sampling time and group were seen for CK, AST, iron, glucose, weight, and length. No significant differences were seen for total weight gain (control, 3.48 ± 0.75 kg; test, 3.85 ± 0.9 kg), and average daily gain (control, 0.12 ± 0.03 kg; test, 0.14 ± 0.03 kg) between trial groups.