The effects of body condition score at drying off and after calving and the rate of loss of body condition score during the dry period on the performance of 2162 cows in eight commercial Israeli Holstein herds were evaluated. The relationships between health, fertility and yield and body condition score were examined by using multiple logistic regressions for measurements with only two outcomes and general linear models for the continuous variables. Herds, parity, season, length of dry period, postparturient diseases, twinning, stillbirth, induction of calving and high somatic cell counts were used as confounding and other exposure variables. Multiparous cows that were underconditioned at calving were culled and exhibited more postparturient uterine diseases. The risk of retained placenta was greater for cows that were underconditioned at drying off, whereas cows that lost more body condition during the dry period suffered more from both retained placenta and metritis; the two effects being independent of each other. An apparent increase in the risk of ketosis associated with over-conditioning at calving could be partly attributed to long dry periods. Cows with a higher condition score at calving were less prone to anoestrus but did not conceive more successfully to first service. A reduction of six open days in primiparous cows was estimated for each additional unit of body condition score at calving. Multiparous cows that lost more body condition during the dry period suffered more from inactive ovaries and were more likely to be open 150 days after calving in the next lactation. Cows calving in a higher body condition score produced more milk, fat and protein in the first 90 days of lactation, the effect being most pronounced on milk fat content.

Abstract.Israel has about 100,000 dairy cows mostly all of Israeli-Holstein-breed, kept in close to 1,000 dairy farms. Most farms are distributed along the Mediterranean Sea coast and in the hot internal valleys. According to the Israeli Herd book the average annual milk production, per cow in 2008 was 11,460 kg, with 3.7% fat and 3.2% protein. Israel's climate is considered "subtropical dry" or Mediterranean, characterized by warm and dry summer with day temperatures above 30 C and relative humidity ranging from 50 to 90%. Climatic limitations brought dairy farmers to develop and implement new technologies and management practices that would enable high milk production and reproduction in summers. In the last three decades the Ministry of Agriculture research units, the extension service and dairy farmers conducted a series of trials and surveys in order to develop an efficient cooling system that will obtain and maintain high milk yield and good reproduction during the hot and humid summer. The cooling system commonly used in Israel is based on a combination of frequent direct watering of the cows, followed by forced ventilation air blowing onto the cows. The system was developed in Israel nearly 30 years ago. A typical cycle is five minutes long and consists of 30 sec of watering followed by 4.5 min of forced ventilation. Providing the cows with 5-7 cooling sessions per day, 30-45 min each, allowed cows, producing 25-30 kg of milk per day to maintain their body temperature below 39.0 C, throughout the day time, on a typical Israeli summer day. At the same time, non-cooled cows had high body temperatures (above 39.5 C), during some part of the daytime and returned to normal body temperatures (below 39.0 C), only for a few hours late at night. In an experiment conducted in 1985-86, conception rate (CR) of cows, cooled as described above, was significantly higher than of non-cooled cows (59 vs. 17% and 57 vs. 17%), for first insemination and for all inseminations, respectively. Pregnancy rate (the amount of pregnant cows out of the eligible cows in the herd) calculated for 90, 120 and 150 days after calving differed significantly between the groups, (44, 59 and 73% vs., 5, 11 and 11%), in cooled and non-cooled cows, respectively. CR and pregnancy rates obtained in intensively cooled herds in this experiment were similar to those obtained during the winter of that year, in commercial dairy farms in Israel. Differently from the results described above, when cows in summer were intensively cooled, only for a period of 2 days before and 8 days after A.I, CR failed to improve (31 and 36%), in cooled and non-cooled cows, respectively. These results offer a conclusion that cows must be intensively cooled and must maintain normal body temperatures during the entire day and during the whole summer. i.e. the entire reproductive process from follicular development until implantation of the embryo in the uterus, in order to express cow's full reproductive potential in Israeli summer conditions. The effect of cooling intensi...

Epizootic hemorrhagic disease is caused by a Culicoides-borne Orbivirus. In cattle, the disease is characterized by reduced milk production and mortality. Recent outbreaks of epizootic hemorrhagic disease virus (EHDV) in North Africa, Israel, and Turkey increase the risk of its invasion into central and northern Europe. An outbreak of EHDV in Israel during the fall of 2006 enabled an assessment of the consequent production losses to the dairy cattle industry. Reduction in milk production and involuntary culling were modeled using a 4-yr database of monthly milk and mortality records from 48 affected and 63 unaffected herds. These indices were compared between periods of outbreak and no outbreak and assessed for various levels and exposure onset. Geospatial kriging interpolation of serological results from 127 herds was used to assess the total outbreak losses for the dairy cattle industry in Israel. Herds affected during the first, second, and third month of the outbreak (September-November) experienced an average loss of 207 (95% CI=154-261), 137 (63-211), and 52 (27-76) kg of milk/milking cow, respectively, during the outbreak period. An average excess mortality and involuntary culling of 1.47/100 cows was documented in herds affected in September. High correlation was observed between EHDV seroprevalence and milk loss; average milk loss for herds with seropositivity of 26 to 50, 51 to 75, and 76 to 100% was 84, 133, and 204 kg of milk/milking cow, respectively. A 1.42% (0.91-1.93%) increase in mortality was observed in herds with seroprevalence above 50%. Losses for the dairy cattle industry interpolated from these data were estimated at US$2,491,000 (US$1,591,000-3,391,000), an average loss of US$26.5/cow in the Israeli dairy cattle. This equals 0.55% of the average total value production of a dairy cow in Israel. This is the first study to estimate the production losses caused by EHDV or any bluetongue-like disease.

Silage is an important feed source for intensive dairy herds worldwide. Fungal growth and mycotoxin production before and during silage storage is a well-known phenomenon, resulting in reduced nutritional value and a possible risk factor for animal health. With this in mind, a survey was conducted to determine for the first time the occurrence of mycotoxins in corn and wheat silage in Israel. A total of 30 corn and wheat silage samples were collected from many sources and analysed using a multi-mycotoxin method based on LC-MS/MS. Most mycotoxins recorded in the present study have not been reported before in Israel. Overall, 23 mycotoxins were found in corn silage; while wheat silage showed a similar pattern of mycotoxin occurrence comprising 20 mycotoxins. The most common post-harvest mycotoxins produced by the Penicillium roqueforti complex were not found in any tested samples, indicative of high-quality preparation and use of silage. Moreover, none of the European Union-regulated mycotoxins--aflatoxin B1, ochratoxin, T-2 toxin, diacetoxyscirpenol and deoxynivalenol--were found above their limits of detection (LODs). The Alternaria mycotoxins--macrosporin, tentoxin and alternariol methyl ether--were highly prevalent in both corn and wheat silage (>80%), but at low concentrations. The most prominent (>80%) Fusarium mycotoxins in corn silage were fusaric acid, fumonisins, beauvericin, monilifomin, equisetin, zearalenone and enniatins, whereas in wheat silage only beauvericin, zearalenone and enniatins occurred in more than 80% of the samples. The high prevalence and concentration of fusaric acid (mean = 765 µg kg⁻¹) in Israeli corn silage indicates that this may be the toxin of highest potential concern to dairy cow performance. However, more data from different harvest years and seasons are needed in order to establish a more precise evaluation of the mycotoxin burden in Israeli silage.

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