Grazing behaviour,physical activity and metabolic profile of two Holstein strains in an organic grazing system

The challenge for sustainable organic dairy farming is identification of cows that are well adapted to forage‐based production systems. Therefore, the aim of this study was to compare the grazing behaviour, physical activity and metabolic profile of two different Holstein strains kept in an organic grazing system without concentrate supplementation. Twelve Swiss (H_CH; 566 kg body weight (BW) and 12 New Zealand Holstein‐Friesian (H_NZ; 530 kg BW) cows in mid‐lactation were kept in a rotational grazing system. After an adaptation period, the milk yield, nutrient intake, physical activity and grazing behaviour were recorded for each cow for 7 days. On three consecutive days, blood was sampled at 07:00, 12:00 and 17:00 h from each cow by jugular vein puncture. Data were analysed using linear mixed models. No differences were found in milk yield, but milk fat (3.69 vs. 4.05%, P = 0.05) and milk protein percentage (2.92 vs. 3.20%, P < 0.01) were lower in H_CH than in H_NZ cows. Herbage intake did not differ between strains, but organic matter digestibility was greater (P = 0.01) in H_CH compared to H_NZ cows. The H_CH cows spent less (P = 0.04) time ruminating (439 vs. 469 min/day) and had a lower (P = 0.02) number of ruminating boli when compared to the H_NZ cows. The time spent eating and physical activity did not differ between strains. Concentrations of IGF‐1 and T3 were lower (P ≤ 0.05) in H_CH than H_NZ cows. In conclusion, H_CH cows were not able to increase dry matter intake in order to express their full genetic potential for milk production when kept in an organic grazing system without concentrate supplementation. On the other hand, H_NZ cows seem to compensate for the reduced nutrient availability better than H_CH cows but could not use that advantage for increased production efficiency.     

Dairy sheep production research at the University of Wisconsin-Madison,USA-a review

Commercial milking of sheep is a new agricultural industry in the United States starting approximately 30 yr ago. The industry is still small, but it is growing. The majority of the sheep milk is used in the production of specialty cheeses. The United States is the major importer of sheep milk cheeses with 50 to 60% of annual world exports coming to the United States during the past 20 yr. Therefore, there is considerable growth potential for the industry in the United States. The only dairy sheep research flock in North America is located at the Spooner Agricultural Research Station of the University of Wisconsin-Madison. The research program started in 1993 and has been multifaceted; dealing with several areas important to commercial dairy sheep farmers. The East Friesian and Lacaune dairy breeds were compared and introduced to the industry through the research program. Both dairy breeds produced significantly more milk than traditional meat-wool breeds found in the U.S., but the two breeds differed in their production traits. East Friesian-cross ewes produced more lambs and slightly more milk than Lacaune-cross ewes whereas Lacaune-cross ewes produced milk with a higher percentage of fat and protein than East Friesian-cross ewes. Lactation physiology studies have shown that ewes with active corpora lutea have increased milk yields, oxytocin release during milking is required to obtain normal fat percentages in the milk, large udder cisterns of dairy ewes can allow for increased milking intervals, and short daylengths during late pregnancy results in increased milk yield. In the nutrition area, legume-grass pastures and forages with a higher percentage of legume will result in increased milk production. Grazing ewes respond to additional supplementation with increased milk yield, but it is important to match the supplement to the quality of the grazing. Ewes on high quality legume-grass pastures that are high in rumen degradable protein respond with increased milk production to supplements high in energy and/or     

The Effects of Trypanosomosis on Sperm Morphology in Zebu×Friesian Crossbred Bulls

Detailed studies of sperm morphological abnormalities were carried out on 12 Zebu x Friesian crossbred bulls used in a study of the effects of trypanosomosis. Four bulls were infected with T. vivax, another four with T. congolense, while four served as controls. The infected bulls developed chronic trypanosomosis. All the bulls initially had very low sperm morphological abnormalities that were within acceptable limits for fertile animals. After infection there was a rapid and progressive increase in all sperm abnormalities. Spermatozoa of infected bulls were highly deformed with multiple morphological defects. Mean percentage pre-infection baseline values prior to infection for acrosomal, sperm-head, detached heads, proximal cytoplasmic droplets, distal cytoplasmic droplets, sperm-tail, midpiece and total sperm morphological defects ranged between 0.1 +/- 0.1 for acrosomal and 8.3 +/- 3.2 for total morphological abnormalities in the semen of the bulls. All the infected bulls developed sperm morphological abnormalities of more than a mean of 40.0% from the 4th week after infection until the end of the investigation and were considered unfit for breeding. At 7 weeks post-infection (PI) until the end of the study (12 weeks PI), the controls had a mean of less than 5% sperm morphological defects, while the infected bulls had 100%. Mean percentage values of sperm morphological defects throughout the duration of the investigation for control bulls were low and within the normal range for fertile bulls. These values differed significantly (p<0.001) from the elevated values of the infected bulls. The results show that trypanosomosis due to T. vivax or T. congolense infection can render Zebu x Friesian crossbred bulls unfit for breeding within a very short time. The resultant infertility could be of economic importance in trypanosomosis-endemic sub-Saharan Africa where Zebu x Friesian crossbred bulls are kept.     

Hepatic encephalomyelopathy in a calf with congenital portosystemic shunt (CPSS)

A 4-month-old female Holstein Friesian calf was referred to the Veterinary Teaching Hospital, University of Berne, Switzerland for evaluation of ataxia, weakness, apathy and stunted growth. Clinical examination revealed generalized ataxia, propioceptive deficits, decreased menace response and sensibility. Postmortem examination did not reveal macroscopic changes of major organs. Histologically, the brain and the spinal cord lesions were characterized by polymicrocavitation, preferentially affecting the white matter fibers at the junction of grey and white matter and by the presence of Alzheimer type II cells. The liver revealed lesions consistent with a congenital portosystemic shunt, characterized by increased numbers of arteriolar profiles and hypoplasia to absence of portal veins. The pathological investigations along with the animal history and clinical signs indicated a hepatic encephalomyelopathy due to a congenital portosystemic shunt.     

Colonic volvulus with defects of the mesenteric attachments in a yearling Friesian colt

This report describes an unusual case of colonic volvulus associated with multiple mesenteric abnormalities. A yearling Friesian colt presented with signs of colic that persisted despite analgesia. The colt showed signs of circulatory compromise and had abnormal findings on rectal palpation. An exploratory laparotomy was performed. A complete volvulus of the ascending colon was identified associated with multiple mesenteric anomalies of unknown aetiology. The colt was subjected to euthanasia due to the extent of the intestinal damage and the likelihood of recurrence. The authors speculate that the anomalies may have been of genetic aetiology associated with a restricted gene pool.     

Thoracic aortic rupture in horses

The aorta can rupture at the aortic root or aortic arch. In most breeds, the aortic root is the likely site and rupture leads to aortocardiac fistula with communication between the aorta and the right atrium, right ventricle and/or the interventricular septum. There is a high prevalence of aortic rupture in young Friesian horses and rupture occurs at the aortic arch with pseudoaneurysm and potentially aortopulmonary fistulation. Echocardiographic and post‐mortem techniques must be adapted to identify aortic arch rupture that is not generally identified with standard approaches. Given the narrow genetic base of the Friesian breed and the significant differences found in extracellular matrix composition and metabolism between Friesians and Warmbloods, genetic factors are likely to contribute to the condition in the Friesian breed.     

Effects of a novel missense polymorphism within the SIGLEC5 gene on fertility traits in Holstein‐Friesian cattle

The aim of the study was to find functional polymorphism within two exons of the SIGLEC5 (sialic acid‐binding Ig‐like lectin‐5) gene and to examine its effects on the production and fertility traits of cows and bulls. Two hundred seventytwo Holstein‐Friesian cows and 574 bulls were included in the study. Novel missense polymorphism (A > G) within exon 3 causing substitution of amino acid arginine by glutamate in position 260 of SIGLEC5 protein (R260Q) was identified by sequencing and digestion by restriction enzyme Msp I. Basic production and fertility traits of cows and estimated breeding values (EBV) of bulls were analysed. The study demonstrated a significant association of SIGLEC5 R260Q polymorphism with days open and calving interval in cows as well as with breeding value for calving interval in bulls. An opposite effect of SIGLEC5 alleles for production and fertility traits was observed: the allele G increased the breeding value for the protein yield, while the allele A increased the breeding value for the calving interval. The current study suggests the involvement of SIGLEC5 R260Q polymorphism in biological processes related to fertility traits. This finding can be applied as a biomarker for a genetic improvement programme in Holstein‐Friesian cattle.     

Therapeutic potential of amniotic fluid stem cells to treat bilateral ovarian dystrophy in dairy cows in a subtropical region

Amniotic fluid is a rich source of multipotent mesenchymal stem cells (MSCs). Amniotic fluid stem cells (AFSCs) have become a new source of stem cells; they have low immunogenicity and are easily harvested. For this reason, they may be useful in clinical tissue engineering. Moreover, AFSCs have anti‐inflammatory properties and can repair tissues. This study evaluated the utility of AFSC injection to treat bilateral ovarian dystrophy in Holstein‐Friesian cows. Bovine AFSCs (BAFSCs) were collected at slaughter from Holstein‐Friesian cows during the third or fourth month of pregnancy and cultured in vitro. The BAFSCs began to show a fibroblast‐like morphology. They were positive for β‐integrin, CD44, CD73, CD106 and Oct4 and negative for CD34 and CD45. After induction, the cells differentiated into mesodermal lineages. Bilateral ovarian dystrophy was confirmed by ultrasonography in 16 lactating cows. The subsequent experiment lasted 15 weeks. Serum was collected weekly to analyse progesterone concentrations, and weekly ultrasonography recorded ovarian changes. Each cow was equipped with an automatic heat detection system to facilitate oestrus observation and breeding records. The progesterone concentration of two cows in the treatment group (25%) significantly increased during weeks 10–15. On ultrasonography, the treatment group demonstrated mature follicles after BAFSCs injection, and foetuses were visualized approximately 40 days after artificial insemination (AI). Oestrus rates in the control and treatment groups were 0% (0/8) and 50% (4/8), respectively; pregnancy rates were 0% (0/8) and 25% (2/8), respectively. Calves were successfully delivered in both cases of pregnancy. These results show that BAFSCs can alleviate bovine ovarian dystrophy and restore fertility.     

复合微量元素缓释丸对奶牛产奶量及奶品质影响的研究

以产奶的黑白花奶牛２０头,分为两组,每组１０头。在同一日粮和饲养管理条件下,一组投丸,为试验组;另一组不投丸,为对照组。预试期１０ｄ,正试期３２ｄ。试验结果,试验组日平均产奶量１７．７６ｋｇ,对照为１６．３０ｋｇ。试验组比对照组提高８．９５％;校正为４％乳脂率的标准乳的日产奶量,试验组为１５．９９ｋｇ,对照组为１３．９４ｋｇ,试验组比对照组提高１４．７１％;