جستجوی مقالات مرتبط با کلیدواژه « calves » در نشریات گروه « دامپزشکی »

In this study, the ITS-1 region of ribosomal RNA genes of six bovine Eimeria species: E. alabamensis, E. auburnensis, E. bovis, E. cylindrica, E. ellipsoidalis and E. zuernii analysed by PCR and the results of molecular methods analysed to find any relationship between presence of parasites and diarretic status. Studies were conducted in calves aged less than 3 months for a period of 2 years. During the study period, 160 dung samples were collected from neonatal calves and examined first microscopically and then by molecular techniques. Stools were analyzed for the presence of Eimeria Spp. oocysts by Sheather's Sugar Flotation Solution method. DNA was extracted and PCR were done to identify six cattle-adapted specie (E.alabamensis, E.auburnensis, E.bovis, E.cylindrica, E.ellipsoidalis and E.zuernii). Eimeria spp. infection was detected in 15 (9.37%) of 160 calves without a history of diarrhea infection and pathogenic Eimeria spp. was asymptomatic in all animals that was not positively related to the diarrheic status of the calves (P>0.05). According to microscopic analsis 6 species (E.alabamensis, E.auburnensis, E.bovis, E.canadensis, E.ellipsoidalis, and E. zuernii) identified and with molecular technique 3 species (E.auburnensis, E.bovis, E. zuernii) were detected. Different risk factors were considered to affect the rate of infection of calves with this protozoan parasite. For controlling disease, Immune status of the calves should be improved by providing sufficient amount of colostrum within the first 24 hours after birth and good hygiene as well as reducing and monitoring stress levels caused by weaning, a change in feed and overcrowding.

Diagnosis of Cryptosporidium species based on morphological characteristics is very limited and has no taxonomic value alone, and therefore the use of molecular methods removes these limitations to some extent.

The aim of this study was to determine the predominant Cryptosporidium genotypes in calves with diarrhea.

Study were conducted in calves aged less than 3 months for a period of 2 years. During the study period, 160 dung samples were collected from neonatal calves and examined first microscopically and then by molecular techniques. Stools were analyzed for the presence of Cryptosporidium oocysts by Sheather's Sugar Flotation Solution followed by Ziel-Neelsen staining method. DNA of parasite was extracted and multiplex nested-PCR protocol basis on the 18srRNA were done to identify three cattle-adapted species (C. andersoni, C. bovis and C. ryanae) plus the zoonotic species C. parvum.

110 fecal samples were collected from livestock in Alborz province and 50 fecal samples were collected from livestock in Shahroud city. Of the 160 animals examined, 90 were female and 70 were male. In total, out of 160 animals examined, 85 cases (53.12%) had diarrhea, of which 55 cases (34.37%) were positive using Ziel-Neelsen staining. Since all positive cases were related to diarrhea samples and related to calves under one month old, a significant relationship was observed between diarrhea status and the presence of this parasite (p < /em><0.05). In terms of seasonal distribution, no difference was observed in the rate of diarrhea and positive parasitic cases. The presence of 305 bp band in all Ziel-Neelsen positive samples confirmed the presence of C. parvum in all samples.

Neonatal calves are more likely to be infected with Cryptosporidium parvum, as confirmed by the present study.

Mucin, a filamentous glycoprotein, is responsible for lubrication and protection of the mucosal epithelia from damages caused by the digesta, digestive secretions, and microorganisms. Goblet cells have potential to secrete granules which is distributed in the intestinal epithelium. The secretory granules contain glycoproteins, including mucins, which are classified into two types, neutral and acidic. The latter can be further differentiated into sulphomucins or sialomucins. There is increased attention to the bovine mucosal immunity because it can aid in preventing colonization and eventually infection of mucosal epithelia. Moreover, mucus is also a selective barrier for absorption across the small intestine. Additionally, as the mucus constitutes the interface between the epithelium and the lumen, mucin could be used as a marker of interaction between the epithelium and dietary components. Measuring the flow of intestinal mucin is a challenge for better understanding the interactions between nutrient digestibility and the gastrointestinal mucosa. The ileal flow of mucin in pigs has been estimated indirectly by using hexosamines as markersThirty-two calves (16 males and 16 females) were randomly divided into two treatment groups and fed with starter diets based on corn or barley as the grain source. Starter feeding began on the third day of life, and high quality alfalfa hay and fresh cow milk were fed according to the farm schedule. The calves were weighed at birth and weekly thereafter until weaning. Nutrient digestibility was determined at 2, 6, and 8 weeks of age. Mucin was crudely separated from fecal samples, and correlation of mucin concentration with digestibility parameters and growth characteristics determined. Mucin excretion rate was negatively correlated with the nutrient digestibility; at 8 weeks of ages it has also negatively correlated with feed intake (r=-0.37, P=0.0406). Further research is required to determine the detailed metabolism of mucin in the gastrointestinal tract of calves and its effect on animal performance.

Calves with failure of passive immunity transfer are susceptible to septicemia and enteric and respiratory disease. Some studies have shown that failure of passive immunity transfer affects animal performance even in older ages. The aim of this study was to evaluate the failure of passive immunity transfer in calves in the traditional farms of Neyshabour. For this purpose, in 3th day after birth, blood samples were gathered from 98 calves. The results showed that mean total protein is 6.46 ± 1/06 gr/dl. There was a significant difference in total protein concentration in male and female calves (p=0.004). Serum total protein concentration was less than 5.2 gr/dl only in 6 of calves (6.1%). 5 of them were male (9% of male calves) and only one case (6.2% heifers) was female. The mean serum globulin in examined calves was 3.37 ± 1.12 gr/dl. There was a significant difference in globulin concentration in male and female calves (P=0.006). It indicates that more immunoglobulin absorption has been happened in the female calves. The amount of IgG was classified as 1 (week transfer), 2 (moderate transfer) and 3 (good transfer). Passive transfer was done good in 93.9% calves and the rest of the cases (6.1%) had a moderate passive transfer. There was a significant and high association between total protein and globulin (P0.01, r= 0.968).

Heat treatment of colostrum has been suggested as a control measure to eliminate or reduce the transfer of colostrum-borne pathogens to dairy calves. The aims of this study were to determine the effects of on-farm heat treatment of bovine colostrum on colostral bacterial counts and IgG concentration and evaluation of passive transfer of immunity in neonatal dairy calves. Ninety-six L of first milking colostrum was collected from Holstein cows and pooled to create a uniform batch. Twenty-four calves were enrolled in 4 treatment groups before suckling occurred and fed raw colostrum (n=6), heat-treated colostrum at 60 ºC for 30 min (n=6), heat-treated colostrum at 60 ºC for 60 min (n=6) and heat-treated colostrum at 60 ºC for 90 min (n=6). Colostrum samples were collected before and after heat treatment and cultured for total bacterial count and analyzed for total IgG concentration. For the first and second feeding 2 L of colostrum was bottle fed by 2 and 12 h of age respectively. Serum samples were collected from calves at 0 h (precolostrum) and 6, 24, 48, 72 h (postcolostrum) and analyzed for serum total protein and IgG concentrations. Heat treatment of colostrum at 60 ºC for 30 and 60 min reduced total bacterial count, yet maintained colostrul IgG concentration compared to the control. There was no difference between treatment groups when examining serum total protein and IgG concentrations, but apparent efficiency of IgG absorption was significantly greater at 6 h in calves that were fed heat-treated colostrum compared to calves fed raw colostrum. There was no effect of on-farm batch heat treatment of colostrum at 60 ºC till 90 min on serum concentration of IgG.

Annexins (including annexin A1 and annexin A2) are important proteins which have some roles in organisms such as intracellular signal conduction, membrane cellular skeletal connection, cellular proliferation and differentiation, especially inhibitory function in inflammation processing. Pasteurella multocida is the most common bacterial pathogen and has high prevalence in pneumonia.
This study was aimed to determine experimentally annexin A1 and annexin A2 in the serum of calves affected by Pasteurella multocida pneumonia. In this research, 10 male calves (2 - 4 months) were allocated to two equal groups, one group as the case: 300 ml in dilution 2×109 CFU Pasteurella multocida bacteria and the other as control group: 300 ml normal saline inoculated by special lavage catheter through oral to trachea. Clinical scores were recorded based on available tables. In treatment group, about 18 to 24 hours after inoculation and synchronous with observation clinical signs changes, bronchoalveolar lavage for cytology and bacteriology examination were done of fluids results from washing. Blood sampling was taken from calves jugular vein in both groups then blood serums were examined by using ELISA kits.
The rates of annexin A1 and annexin A2 in blood serum of treatment group showed significant increase (using independent t test) compared to control group (p It seems these annexins (annexin A1 and annexin A2) can be used as important biomarkers in blood serum to diagnose inflammation processes such as pneumonia.

Cryptosporidium parvum is a protozoan parasite which belongs to apicomplexa phylum. The parasite infects both wild and domesticated animals and human beings as well. The purpose of the present study was to detect oocyst shedding and diarrhea pattern in experimental cryptosporidiosis and their correlation with weight loss in neonatal calves. Twelve Holstein calves of both sexes were obtained at birth from dairy farm and randomly divided into two groups of 6 calves. Six calves were orally infected with 107 C. Parvum oocysts at the 12h post parturition. The control group was not infected. Clinical signs were examined and fecal samples were collected by the rectal examination twice a day. All calves were weighed from day 0 to day 30 with 3 days intervals to determine effects of cryptosporidiosis on weight gain. All infected calves were noticeably depressed and had a decreased appetite from 3 days post inoculation (DPI) while they received colostrum. Subsequently، watery diarrhea with clumps of mucus and yellow or pale changes of feces color were observed. The infected calves have had diarrhea for 5-8 days that remarkably had got dehydrated. The most severity of diarrhea was 4-6 DPI. Oocyst excretion started 4 DPI، peaked at 6 DPI (60. 48×106±9. 03oocysts/g feces) and continued until 11 DPI. Control calves had no diarrhea and other clinical signs during the whole period of the trial. The mean weight gain of control group was significantly higher than inoculated group during experiment (p<0. 001). The Weight of the infected calves was retarded until 9 days old and then risen subsequently. Present study showed the role of C. Parvum as the primary cause of diarrhea and weight loss among neonatal calves.

Cryptosporidium andersoni is a pathogenic coccidia of cattle and sheep. In the present study، 940 fecal samples were investigated from calves aged from 2 months to 1 year old of Shahriar city. The smears of the samples were stained with modified Ziehl Neelsen technique. For molecular study، DNA was extracted by phenol-chloroform from stool positive samples، then 18s rRNA gene of Cryptosporidium was amplified by Nested PCR method. The resulted band was cut with two restriction enzymes (Vsp1 and Ssp1). Finally the resulting amplicon of Nested PCR was sequenced. The results indicated that، 23 cases were diagnosed to be positive with staining technique. All PCR-RFLP patterns of 18S rRNA gene of calve samples showed similar electrophoretic mobility on agarose gel and identified as Cryptosporidium andersoni. The result was also confirmed by sequencing analysis.

Cryptosporidium is an intracellular protozoan parasite that known as the major cause of diarrhea in human and animals. The level of infection to Cryptosporidium in diarrheic calves of livestock around Tehran and the role of risk factors on its emergence were studied. 200 fecal samples from diarrheic calves of livestock's around Tehran city were collected by cluster sampling method and were studied by modified Ziehl-Neelsen staining method. Existence of Cryptosporidium infection was confirmed in 18 calves (9%). Incidence rate of the infection did not have any significant relationship with sex of animals (p=0.928) and diarrhea history (p=0.640), but the incidence rate of the infection was more in suckling calves with age of less than 2 months with dry fertilizer bedding. Cryptosporidium is an intracellular protozoan parasite that known as the major cause of diarrhea in human and animals. The level of infection to Cryptosporidium in diarrheic calves of livestock around Tehran and the role of risk factors on its emergence were studied. 200 fecal samples from diarrheic calves of livestock's around Tehran city were collected by cluster sampling method and were studied by modified Ziehl-Neelsen staining method. Existence of Cryptosporidium infection was confirmed in 18 calves (9%). Incidence rate of the infection did not have any significant relationship with sex of animals (p=0.928) and diarrhea history (p=0.640), but the incidence rate of the infection was more in suckling calves with age of less than 2 months with dry fertilizer bedding. According to the reports of Cryptosporidium infection in multiple studies from different regions of Iran, recognizing the risk factors on the infection incidence can have an important role in controlling the protozoan. According to the reports of Cryptosporidium infection in multiple studies from different regions of Iran, recognizing the risk factors on the infection incidence can have an important role in controlling the protozoan.

In this study, the effect of chamomile extract on the ability of neonatal calves to absorb immunoglobulin G (IgG) was evaluated. An ethanolic extract of chamomile was obtained with the concentration of 111 mg/ml. Calves were randomly divided into four groups, each receiving one of four chamomile treatments; 1: low dose (LC; 5.5 mg/kg body weight; 2: moderate dose (MC; 11 mg/kg); 3: high dose (HC; 22 mg/kg); 4: a control (CO; normal saline). Chamomile extract was injected intravenously into the jugular vein 1 h after birth and before colostrum intake. There was no significant difference in concentration of serum IgG between LC and CO calves (P = 0.792). MC calves had a significantly higher serum IgG concentration at 48 h compared with LC and CO calves (P = 0.002, P = 0.003, respectively). There was no statistical difference between MC and HC calves at 48 h (P = 0.264). These results show that chamomile extract could promote colostral IgG absorption in neonatal calves if a suitable dose is given immediately after birth.

In order to estimate the mean of maternal antibody in calves against BHV-1 (Bovine Herpes virus type 1), this study was carried out in a population of calves from non-vaccinated dairy cattle at 2 livestock in Qazvin province. One hundred thirteen sera out of 512 were collected from 1-4 months unvaccinated calves. We used Blocking –Percentage of maternal antibodies against BHV-1, which obtained by Blocking ELISA assay in 1-4 months calves sera. The result of one way analysis of variance determined that there was a significant difference among blocking percentage of maternal antibodies against BHV-1 in 1-4 months (P<0.001). Comparing percentage of mean titer indicated a decreasing trend with respect to age i.e. from 84.4(a 95% CI: 78.1- 90.6) in 1 month to 57.6(a 95% CI: 47.1- 68.2) in 4 months, which was near to 55 as cut off point. Tukey's method showed a significant difference between the Blocking percent of mean titer between 1 and 4(P<0.001), 2 and 4 (P=0.034) months. Chi-square test for independency showed a significant association between age and seroactivity (P=0.005).

This study was conducted in order to evaluate the role of selenium supplement consumption in pregnant heifer in late permanency on selenium, glutathione peroxidase serum levels in heifers and newborn calves. 16 heavy pregnant heifers were selected and divided into two control and treatment groups with 8 heifers. The environmental, management and nutrition conditions were the same. In treatment group selenium supplement was consumed 1mg/day for 30 days. In Zero day and in delivery period blood samples were drawn from neck vessel in heifers, then blood samples were drawn from calved when birth and 48 hours hater. After removing serum, selenium serum level and glutathione peroxidase level were measured by atom absorption method and biochemical kit respectively. In heifers selenium and glutathione peroxidase serum level increased meaningfully in treatment group (p=0.003, p= 0.008), in calves selenium serum level increased meaningfully in treatment group (p= 0.042) but glutathione peroxidase serum level did not increase meaningfully (p=0.076). In treatment calves selenium and glutathione peroxidase were increased 48 hours after birth but it was not meaningful. (p=0.88, p=0.052). It was concluded that selenium supplement consumption in late preganancy cause to increase in selenium and glutathione peroxidase serum in heifers and calves that can be beneficial as a antioxidant. It is recommended as a cow ration supplement.

The present investigation was performed to determine the effect of long-term administration of sodium selenite on the biochemical indices and concentration of thyroid hormones in calves. Sodium selenite solution was drenched at 0.1 and 0.25 mg per kg body weight for 12 weeks. Higher dose produced characteristic symptoms of selenosis whereas mild symptoms were observed with lower dose. The toxic symptoms appeared when blood selenium level was 1.68 ± 0.13 mg per ml. There was a significant (P<0.05) increase in the activities of the aspartate aminotransferase, alkaline phosphatase, blood urea nitrogen and creatinine levels in the treated animals. The repeated administration of sodium selenite resulted in a significant p-value decline in thyroxine levels on the 10th week and increase in triiodothyronine on the 8th week of treatment. The findings of the present study suggested that sodium selenite induced selenosis alters thyroid hormone levels in plasma.