Inclusion of brown midrib dwarf pearl millet silage in the diet of lactating dairy cows.

Brown midrib brachytic dwarf pearl millet (Pennisetum glaucum) forage harvested at the flag leaf visible stage and subsequently ensiled was investigated as a partial replacement of corn silage in the diet of high-producing dairy cows. Seventeen lactating Holstein cows were fed 2 diets in a crossover design experiment with 2 periods of 28 d each. Both diets had forage:concentrate ratios of 60:40. The control diet (CSD) was based on corn silage and alfalfa haylage, and in the treatment diet, 20% of the corn silage dry matter (corresponding to 10% of the dietary dry matter) was replaced with pearl millet silage (PMD). The effects of partial substitution of corn silage with pearl millet silage on dry matter intake, milk yield, milk components, fatty acid profile, apparent total-tract digestibility of nutrients, N utilization, and enteric methane emissions were analyzed. The pearl millet silage was higher in crude protein and neutral detergent fiber and lower in lignin and starch than the corn silage. Diet did not affect dry matter intake or energy-corrected milk yield, which averaged 46.7 ± 1.92 kg/d. The PMD treatment tended to increase milk fat concentration, had no effect on milk fat yield, and increased milk urea N. Concentrations and yields of milk protein and lactose were not affected by diet. Apparent total-tract digestibility of dry matter decreased from 66.5% in CSD to 64.5% in PMD. Similarly, organic matter and crude protein digestibility was decreased by PMD, whereas neutral- and acid-detergent fiber digestibility was increased. Total milk trans fatty acid concentration was decreased by PMD, with a particular decrease in trans-10 18:1. Urinary urea and fecal N excretion increased with PMD compared with CSD. Milk N efficiency decreased with PMD. Carbon dioxide emission was not different between the diets, but PMD increased enteric methane emission from 396 to 454 g/d and increased methane yield and intensity. Substituting corn silage with brown midrib dwarf pearl millet silage at 10% of the diet dry matter supported high milk production in dairy cows. When planning on farm forage production strategies, brown midrib dwarf pearl millet should be considered as a viable fiber source.

Identification and characterization of lactic acid bacteria isolated from mixed pasture of timothy and orchardgrass, and its badly preserved silage.

In order to understand the relationship between lactic acid bacteria (LAB) species and silage fermentation, a total of 65 LAB strains isolated from mixed pasture of timothy (Phleum pratense L.) and orchardgrass (Dactylis glomerata L.), and its badly preserved silages were subjected to phenotypic and genetic analysis. According to these analyses, the isolates were divided into 13 groups, including Enterococcus gallinarum, Lactobacillus acidipiscis, L. coryniformis subsp. coryniformis, L. coryniformis subsp. torquens, L. curvatus, L. paraplantarum, L. plantarum subsp. argentoratensis, L. plantarum subsp. plantarum, L. sakei subsp. carnosus, Lactococcus garvieae, Lactococcus lactis subsp. cremoris, Leuconostoc pseudomesenteroides, Pediococcus acidilactici, Pediococcus pentosaceus, Weissella hellenica, Weissella paramesenteroides and Carnobacterium divergens. This is the first report to document that C. divergens, L. acidipiscis, L. sakei subsp. carnosus, L. garvieae, phenotypically novel L. lactis subsp. cremoris, E. gallinarum and W. hellenica are present in vegetative forage crops. L. plantarum group strains were most frequently isolated from the badly preserved silages. Some isolates showed a wide range of growth preferences for carbohydrate utilization, optimal growth pH and temperature in vitro, indicating that they have a high growth potential. These results are useful in understanding the diversity of LAB associated with decayed silage of timothy and orchardgrass.

[Tremorgenic syndrome in a cattle herd after feeding silage contaminated with A. clavatus]. / Tremorgenes Syndrom in einem Rinderbestand nach Verfütterung einer mit A. clavatus befallenen Silage.

The clinical signs, pathological and laboratory findings of cattle suffering from a tremorgenic syndrome are described. Animals on a farm with a total of 22 cows, 18 heifers and 9 calves were fed mouldy grass and spent malt-grain silage. Five heifers were affected with muscular tremor, hyperexcitability and hypersensitivity. They were ataxic or in sternal recumbency, while their appetite remained normal. Haematology and blood chemistry in two heifers as well as cerebrospinal fluid from one sick animal were unremarkable. The pathological examination of one animal brought no macroscopic changes to light. Histological examination, however, revealed the degeneration of motor neurones in the midbrain, brain stem and spinal cord. Analysis of a silage sample provided evidence of the presence of Aspergillus clavatus, a mould capable of producing neurotoxic tremorgenic mycotoxins. Epidemiology, clinical findings, pathology and microbiological examination suggest that the five cattle were suffering from neuromycotoxicosis.

[Senecio jacobaea: deceiving beauty. Senecio jacobaea poisoning]. / Jacobskruiskruid: bedrieglijke schoonheid. Vergiftiging met Senecio jacobaea.

In a cattle herd problems were noticed during 1.5 years, characterised by emaciation and loss of milk production with lower fat- and protein%, tenesmus, central nervous symptoms (aggression, circling and blindness), diarrhoea, eczema solare and death. Clinical, laboratory and post mortem examinations did not reveal a specific cause at first. An intoxication was suspected based on the clinical symptoms, the course of the disease in sick animals and severe liver cirrhosis found in a sudden death cow: The animals were fed grassilage derived from an air force base on which an overwhelming amount of tansy ragwort (Senecio jacobaea) was present. On subsequent microscopic examination of the livers of 11 slaughtered clinically healthy animals all of these showed fibrosis in varying extension. Cirrhosis and fibrosis of the liver and the clinical symptoms are all features of chronic pyrrolyzidine alkaloidosis. Tansy ragwort poisoning has not been diagnosed in the Netherlands for years. The rise in cases is due to more extensive use of land.

Sweet clover poisoning in dairy cattle in California.

Eight of 600 Holstein heifers and cows died after ingestion of sweet clover silage (Melilotus sp) that contained excessive concentrations of dicumarol caused by mold infestation. The cattle developed subcutaneous hemorrhages and bled from the vagina, became weak, were unable to move, and died. To the best of our knowledge, this is the first report of sweet clover poisoning in cattle from California and is discussed in light of previous findings in the Midwest and Canada. Sweet clover poisoning is caused by dicumarol, a fungal metabolite produced from substrates in sweet clover, and is a common livestock problem in the Northern Plains and Canada. Sweet clover poisoning should be considered in livestock animals with clinical evidence of hemostatic dysfunction, prolonged coagulation times, subcutaneous hemorrhages, and hemorrhagic abortions. Definite diagnosis of moldy sweet clover poisoning can be accomplished by analysis of serum and feed samples for dicumarol concentrations.

Lead concentrations in blood and milk from periparturient dairy heifers seven months after an episode of acute lead toxicosis.

In September 1988, 100 of 300 yearling dairy heifers developed blindness, tachypnea, foaming at the mouth, chewing, and facial fasciculations. Twenty-five animals died. Lead toxicosis was diagnosed based on the clinical signs and the presence of excessive concentrations of lead in whole blood, liver, kidney, and rumen contents of affected animals. The source of the lead was sudan grass silage that had been contaminated by soil that contained up to 77,000 mg/kg of lead. Lead concentrations were determined approximately 7 months after the acute episode of lead toxicosis. Whole blood and milk samples were obtained from heifers and a group of control cows 2 weeks prior to (blood only), at the time of, and 2 and 4 weeks after freshening. No lead was found in any of the milk samples (detection limit = 0.055 mg/liter). Animals that had been severely affected by lead toxicosis experienced a transient increase in whole blood lead concentrations at freshening that was not high enough to be considered toxic. No similar increases in blood lead were observed for control cows or heifers that had experienced milder toxicosis. These findings suggest that at parturition lead is mobilized into the blood of cattle previously exposed to excessive lead.

Clostridium botulinum type B toxicosis in a herd of cattle and a group of mules.

Clostridium botulinum type B toxicosis was diagnosed as the cause of generalized weakness and death in a group of cows and mules fed from the same batch of rye silage. One severely affected cow was treated and recovered, as did other less severely affected cows. All affected mules died. The remaining cattle in the herd were then vaccinated before continued feeding of the silage.

Hepatic encephalopathy in feedlot calves.

A case of bovine hepatic encephalopathy occurred in southwest Kansas. Of 548 calves involved, 150 died over 30 days. The suspected cause of the condition was an unidentified hepatotoxin from moldy silage. The syndrome was experimentally reproduced in silage fed laboratory mice.

[The occurrence of a toxigenic strain of Fusarium tricinctum in connection with disease in a dairy cow]. / Výskyt toxigenního kmene Fusarium tricinctum v souvislosti s onemocnením dojnice.

The fungus Fusarium tricinctum, producing T-2 toxin, was isolated from mouldy maize silage. T-2 toxin was identified by TLC and by a bioassay. Consumption of mouldy silage resulted in a disease in a dairy cow, which had to be killed. The patho-anatomical findings obtained in the slaughtered cow generally suggested trichothecene poisoning. It was derived from these findings that the disease was due to the presence of trichothecenes in the feed.