Experimental teat anastomosis for treatment of severe cow’s teat injuries were performed for the first time and evaluated by radiography.Five healthy, non-pregnant milkier Holstein cows were selected and after preoperative considerations, the rear teats were prepared for aseptic surgery. The left teats (1/3 of distal portion) were amputated horizontally and full thickness elliptical incisions were induced in 1/3 of proximal of the right teats from the base, in medial aspect.Anastomosis between amputated and neighboring teats was completed with two rows of sutures, simple interrupted in mucosal layer and interrupted horizontal mattress in intermediate and skin layers with polyglactin910 (Coated Vicryl), sized 3-0 and 2-0, respectively. Radiographs with meglumine compound (positive contrast media) were prepared under condition of FFD=80 Cm, 50 Kv, 20 mAs from all anastomised teats with and without positive pressure in 3 day before surgery and 4, 15, 30 and 44 days after the operation.According to radiographic results inner diameter of anastomosis junction were measured 14-20 mm under positive pressure and 11-16 mm without positive pressure in 44th day after the operation.According to the good radiographic findings and simplicity of this surgical technique, Teat anastomosis can be recommend for the treatment of severe teat injuries in dairy cows.  

Objective: Usually sever and progressed lesions in distal end of teat results to economic losses due to inability of milking of affected quarter, increase possibility risk of mastitis and early culling. The new technique of anastomosis between affected and its normal neighboring teats can be an alternative surgical method to prevention of lost of quarter lactation and subsequent adverse effects on mammary gland parenchyma and early culling from milking herds.Design: Descriptive study.Animals: Five healthy, non-pregnant Holstein cows.Procedure: The rear teats were prepared for aseptic surgery. The left teats (1/3 of distal portion) were amputated horizontally, and full-thichness elliptical incisions were induced in 1/3 of proximal of the right teats from the base, in medial aspect. Anastomosis between amputated and neighboring teats was completed with two rows of sutures, simple interrupted in mucosal layer and interrupted horizontal mattress in intermediate and skin layers with polyglactin 910 (Coated Vicryl), sized 3-0 and 2-0, respectively.Results: Healing process during the study (45 days) was very good, without any milk leakage or fistula formation. No clinical sign of mastitis was observed and from milk samples of anastomated teats no bacteria was isolated in culture. Milking with machine after removal of skin sutures was done without any difficulty. There was no considerable difference in total milk volume of rear quarters after anastomosis in comparison with before surgery. Milking time of the anastomated quarters was a little more than before anastomosis.Conclusion: According to the clinical findings of this study, it could be concluded that the introduced new technique of teat anastomosis could be performed in severe and progressed lesions in distal end of teat in dairy cattle to maintain total capacity of milk production of cow.

Predisposing factors (bacteremia, endothelial damage, ...) are important for development of endocarditis in cattle. A dairy cow was referred to Teaching hospital of veterinary faculty. Clinical examination revealed cardiac murmur on auscultation and a chronic abscess on thorax. There was a constant neutrophilia and progressive anemia in cell blood count (CBC). Endocarditic was diagnosed clinically. Because of poor prognosis the cow was slaughtered and vegetative valvular endocanditis accompany by one hydatid cysts on right atrium were found. Actinomyces pyogenes was isolated from lesions. This is the first report of concurrent hydatid cysts and endocarditic in dairy cattle.

Objective: Considering the country's need for livestock products, it is very necessary to establish and develop dairy cattle breeding units in the country. On the other hand, there are many challenges in the value production chain of this sector. The aim of the current research is to identify the challenges of the dairy cow value production chain. Methods: This research is descriptive in terms of practical purpose, in terms of control of field variables and in terms of data collection method. The research tool was a researcher-made questionnaire. The statistical population was specialists, activists and experts in the dairy cattle production sector in Iran. The reliability and validity of the questionnaire were confirmed using Cronbach's alpha coefficient and content validity method, respectively. Data analysis was done using SPSS software at two levels of descriptive and inferential statistics. Results: According to the results, the most important challenges are, in order of providing financial resources, challenges related to eugenics centers, and administrative and organizational challenges (first to third ranks). Environmental challenges, challenges of cattle products supply and sales centers, and challenges of livestock products transformation and processing industries are in the last ranks (twelfth to fourteenth) of this category. Conclusions: in all challenges, the rank average of each challenge category is higher than its median value, and the average difference in all challenges with the median value is statistically significant.

Six Holstein cows (120±20 d in milk) were used in a 3x3 replicated Latin square design to investigate the effect of different particle sizes of ground barley grain on digestibility, degradation rate and lactation performance. Geometric mean diameters of the barley particles were 0.94, 1.93 and 2.90 mm for treatments 1, 2 and 3, respectively. Diets were only different in barley particle size and all cows received diets containing 40% corn silage and 60% concentrate (DM basis) composed of 50% ground barley. The differences among dry matter intake (DMI), milk fat percentage, milk total solid percentage, daily fat yield, dry matter digestibility, urinary and ruminal pH, daily body weight change, and fecal particle size distribution were not significant. Treatment 3 caused a decrease (P<0.05) in milk protein percentage, daily milk yield and fecal pH compared to treatments 1 and 2; no other treatment differences were significant. With increasing barley particle size, fecal dry matter was increased but daily milk protein yield was decreased (P<0.05). Significant differences (P<0.05) in 4% FCM, 4% FCM/DMI daily, milk lactose yield, daily total solids yield and organic matter digestibility were observed between treatments 1 and 3. No other treatment effects were observed significant. The soluble fraction, the potential degradable fraction, ruminal degradation rate and the effective degradability of dry matter increased linearly for treatments 1, 2 and 3, respectively. It is concluded that fine grinding of barley (0.94 mm) which is commonly used on dairy farms improved OM digestibility, milk yield, milk protein percentage and production and would be recommended for feeding conditions similar to those of the present experiment.

Introduction: To maximize the profitability of livestock industry decisions are based on individual animal yield and other factors such as overall health of animal as well as production and reproduction performance. To increase the revenue changes in replacement policies and breeding are essential (Nasr Esfahani 2018). Accordingly, in Iran issues such as feed price fluctuations and lack of coherent policies increase the economic risk of the dairy cow industry. To better make a decision on elimination or replacement of a cow, the producer shall compare the expected benefits of both keeping or replacing an individual animal. The most important objective of a livestock unit is to maximize the profit of the herd; one of the issues affecting this profit is the criteria and level of elimination (Rogers et al, 1988). If elimination and replacement is not optimal, namely the cows are eliminated sooner or later than the optimal time, the profitability of the herd will decreases. For determining the optimal elimination time point several biological and economic variables shall be concurrently taken into consideration (De Vries, 2006). The elimination decision must be based on predicted future incomes of the cow. Generally, keeping an animal in the herd for a longer time leads to more profit. The proper decision of optimal and reasonable elimination is made by comparing the present value of future liquidity flow (income and expenses) of the current livestock in the herd with the present value of the future liquidity flow of heifer as its replacement. Ultimately livestock with most current value will occupy the position (Groenendall et al. 2005). The application of dynamic programming in the animal sciences mostly is about animal replacement issues. The optimal policy at each stage represents best decision from that stage till the final stage. In this method, an expected value will be calculated for each of the situations that will happened. Furterhmore, the decision maker selects the best decision based on the calculated expected value and upcoming situations. For optimal replacement decision making in dairy herds, several dynamic programming models have been proposed by De Vries et al. (2006) and Van Arendonk et al. (1985). Cardoso et al. (1999) reported optimizing replacement and insemination policies in dairy cows by calculating income, costs and monthly probability of elimination. Material and methods: In this study, we estimated the biological parameters of the herd, including risk of forced elimination and the possibility of pregnancy in different lactation periods and different months after calving based on the data collected from industrial dairy farms (Ardabil city, Iran) between 2015 and 2018. Also, financial data of the herd was also obtained in the form of an economic questionnaire from the studied units and was developed by importing biological parameters and financial data into a bio economic model in Dairy Vip software. This software simulates the livestock over time and calculates the performance of herd based on optimal and non-optimal modes. The basis for optimal elimination decision is to minimize the cost of missed opportunity (cost of rejecting the best alternative when deciding). So that by negating the value of keeping livestock (obtained from the difference between the net present value of existing livestock and alternative heifers), optional removal will be done. The criteria of optional elimination in the studied herds were determined to reach the milk production of non-pregnant cows to less than 18 kg/day. Milk production was evaluated using daily milk production records and also fitting the incomplete gamma curve (Wood). The 21-day mean insemination rate and success insemination rate of cow were 49. 3% and 37%, respectively. By default, in Dairy Vip software, a livestock can be in the herd for 24 months maximum after calving. The risk of abortion from the second to the eighth month was 6. 24, 4. 16, 2. 08, 1. 11, 0. 45, 0. 19, and 0. 19%, respectively. Dynamic programming model was developed to determine the optimal replacement policy. The objective function in this study was to maximize the present value of net income from current cows and alternative heifers. In order to estimate the expected statistics under optimal policy, Markov chain simulation was used. Results and discussion: With the implementation of optimal policies, the annual elimination rate increased from 30. 11% to 43. 80%. However, the forced elimination rate slightly decreased )2. 3%(. The optimal removal rate can vary depending on the economic and biological conditions in the herd. With the implementation of optimal policies, pregnancy rate increased from 15. 31% to 18. 20% and increased by 2. 89%. Correspondingly, it can be concluded that the economic importance of increasing the pregnancy rate is more urgent in herds with weaker reproductive performance. Also, success rate of insemination dropped from 33. 9% in non-optimal mode to 37%, indicating higher likelihood of livestock pregnancy in different months. The 21-day insemination rate increased from 47. 6% to 49. 3%, indicating appropriate cow inoculation. milk production in dairy cows could be increased by reducing the pregnancy days. In this study pregnancy days decreased from 139 to 132 days by optimal policies leading to significantly higher milk production. Furthermore, open days (the interval from calving to the next gestation period) decreased from 167 to 161 days reducing the pregnancy days and subsequently increasing the pregnancy rate. Also, reducing the calving distance from 13. 6 to 13. 3 (0. 3 per month) resulted in higher annual milk production. Optimal policies compared with the nonoptimal policy resulted shorter lactation days thus significantly higher milk production (daily and annual) and performance (Table 3). Daily milk performance increased from 41. 4 to 44. 2 equaling to 3 Liters more milk per cow (annually 935 kg more milk). According to our observations, annual milk yield increased from 12, 548 to 13, 483 kg per cow via the implementation of optimal policies. Moreover, reducing the average lactation days resulted in increase in the daily and annual production of cows by 3 and, respectively. Conclusion: The most important goal of a livestock unit is maximizing the profit of the herd. One of the factors affecting profitability, is criteria and elimination rate. Implementing optimal policies is associated with increased livestock elimination rates and replacement costs and also increased feed costs. However, higher revenue from these policies can compensate the increased costs thus increasing the net profit per cow. One of the basic criteria in estimating the expected present value is to sort the cows in the herd based on future income and expenses, and according to these values, the decision is made to keep or eliminate the cows. So, regardless of these values, cows may be eliminated sooner or later than the optimal time, which reduces the profitability of the herd.