The effect of aging of milk samples on the accuracy of infrared analysis of milk composition]

The effect of a decrease (and/or fermentation) in the lactose content during milk storage under different conditions was investigated on the accuracy of the results obtained on a Milko-Scan apparatus to contribute to the present knowledge of this problem. The results were in agreement with some results cited in the literature. These wavelengths are used for infrared spectrophotometry on the above apparatus: for fat 3.48 microns, for proteins 6.46 microns and for lactose 9.60 microns. Bulk milk samples used for the tests were untreated or treated with potassium dichromate, bronopol, sodium azide and Milkofix at the temperatures of storage in darkness 20 degrees C and 4 degrees C. The differences against the reference values (measured on the first day) were determined and evaluated in milk composition and characteristics as arising during milk storage. These differences were used in form of either cumulative means of differences (Figs. 1 to 5) or individual differences (Fig. 8). In the first part significant correlation coefficients (P less than 0.001) were calculated for the relationship between the variations of lactose content and the fat and protein contents: r = -0.59 and/or -0.73 (Figs. 6 and 7). This suggests that the decrease in the lactose content by 0.10% recorded by the infrared analysis and caused by lactose decomposition is accompanied by a "seeming" increase in the fat and protein content by about 0.04%. In the second part the correlation coefficients for the fat and protein contents r = -0.96 and -0.96 (P less than 0.001; Figs. 9 and 10; Tab. II) were calculated on the basis of an observation of the lactose decrease in an untreated milk sample (20 degrees C for 28 hours). These coefficients are somewhat different from the preceding ones; this is due to the lower homogeneity of the first set where the milk samples were treated in a different way, but the coefficients confirm the same conclusions. The values of the correlation coefficients for the dependence between the development of the acquired titratable acidity (SH) and the variations of fat (F), protein (P) and lactose (L) contents were as follows: r = 0.95; 0.95; -0.99 (P less than 0.001; Figs. 12, 13; Tab. II). Thus the above-mentioned "seeming" increase in the F and P contents can be explained to the extent of 92.2% from the decrease in the L content, which also causes the increase in titratable acidity to the extent of 98.0%.(ABSTRACT TRUNCATED AT 400 WORDS)     

Upper eocene gilled mushroom from the dominican republic

Coprinites dominicana gen.nov., spec.nov. (Coprinaceae) found in amber from the Dominican Republic is the earliest known gilled mushroom, the first fossil fleshy agaric determinable, and the only kiiown fossil "mushroom" (Agaricales) from the tropics. This find is of significance with respect to the evolutionary development of the Basidiomycetes. Because the appearance of this fossil is quite modern, it suggests that mushrooms as a group probably arose much earlier than the early to mid-Tertiary.     

Preservation of fowl semen in liquid nitrogen: Application to breeding programmes

1. A method of freezing semen of individual males was adapted for use under farm conditions using an automated freezing apparatus.

2. An insemination programme to produce high fertility and hatchability with semen which had been deep frozen for 2 months was devised.

3. Over 90% fertile eggs with a 90% hatch of all eggs set was obtained with frozen and thawed semen over a period from the 2nd to the 12th day after the first of four inseminations. The persistency of fertility was also tested and 93, 86.6 and 30.7% of the eggs were fertile during days 2 to 6, 2 to 8 and 9 to 15 after the last insemination.

4. Corresponding with the high fertility rate, chicks were produced by every hen that was inseminated and from every male whose semen was frozen and stored. The implications for future breeding practices of this successful result are discussed.     

Toxoplasma infection and abortion in dairy goats

Summary Serological investigation by the indirect haemagglutination test forToxoplasma antibodies was carried out in a flock of dairy goats. Antibody titres ranging from 1:4 to 1:1,024 were found in 34% of 371 apparently healthy animals. High antibody titres of 1:256 suggestive of recent infection were noted in 18 (4.9%) animals including 13 nannies. The occurrence of a number of non-brucella abortions associated with high serological titres and the isolation of the parasite from the brain tissues of an aborted foetus suggestedToxoplasma as a probable aetiologic factor. Sera having significant levels of haemagglutinating antibodies (1:128) were also found positive to the card agglutination test. Epidemiological aspects and the public health potential of subclinical toxoplasmosis in dairy goats are discussed.

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Infecciones Y Abortos En Cabras Lecheras Debido AToxoplasma

Resumen Se realizaron investigaciones serológicas de toxoplasmosis mediante la prueba indirecta de hemaglutinación en un rebaño de cabras lecheras. Se encontraron títulos de 1:4 a 1:1024 en 34% de 371 animales aparentemente sanos. Títulos de 1:256 sugestivos de infecciones recientes, se encontraron en 18 (4.9%) animales, incluyendo 13 hembras paridas. La ocurrencia de un significativo número de abortos no asociados con brucela, títulos serológicos altos de toxoplasmosis y el aislamiento del parásito del cerebro de fetos abortados, sugiere que eltoxoplasma es el factor etiológico más importante. Se discuten aspectos epidemiológicos de importantcia para la salud pública, relacionados con el potencial de la toxoplasmosis (subclínica) en cabras lecheras.

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Toxoplasmose Et Avortement Chez Les Chevres Latiteres

Résumé Des investigations sérologiques par la méthode de l'agglutination indirecte pour rechercher des anticorps toxoplasmiques ont été faites sur un troupeau de chèvres laitières. Des anticorps ont été mis en évidence chez 34 p.100 des 371 animaux apparemment sains à des titres allant de 1:4 à 1:1024. Des titres élevés d'anticorps atteignant 1:256 ont été relevés chez 18 (soit 4,9 p.100) des animaux comprenant 13 chèvres, ce qui fait penser à une infection récente.L'existence de nombre d'avortements non-brucelliques associés avec des titres sérologiques élevés et l'isolement du parasite des tittus cérébraux d'un foetus avorté suggerent que les Toxoplasmes en ont probablement été le facteur étiologique. Des sérums ayant des taux significativement élevés d'anticorps agglutinants (1:128) ont également été reconnus comme positifs par le test d'agglutination en EAT. Les aspects épidémiologiques et le danger potentiel pour l'homme de ces cas subcliniques de toxoplasmose chez les chèvres laitières sont discutés.

     

Feather damage in hens caged individually

1. The plumage of hens housed singly in cages was generally in good condition after one year. There was slightly more feather loss where hens could peck their neighbours’ plumage (adjacent cages) than where this was not possible (spaced cages).

2. It was concluded that most, though not all, of the feather damage seen in the individually‐caged birds was due to abrasion, but that abrasion was likely to be relatively unimportant in multi‐bird cages.

3. There were no significant differences in egg production or food intake associated with the two kinds of housing.

4. In the adjacent cages there was an increase in maintenance requirement related to increased feather damage, which amounted to about 7% for an increase of about one unit in feather‐loss score. In the spaced cages the increase was less.

5. Hens with increased feather damage also showed increased egg production.     

Apparent independence of glucose tolerance and body fat content in 8‐week‐old broilers

1. A possible relationship between glucose tolerance and body‐fat content was examined in broilers selected at 2 and 4 weeks of age for fast or slow glucose disposal.

2. At 8 weeks of age, selected chickens were different in glucose tolerance but similar in body weight, food conversion efficiency, carcass composition and glucose‐induced insulin release.

3. Therefore, variations in glucose regulation and insulin sensitivity which are detectable at an early age, do not appear to be related to body composition in 8‐week‐old broilers.     

Evaluation of rabbit excreta as an ingredient in broiler diets

1. Dry rabbit excreta were found to contain 188.1 g crude protein, 6.6 g non‐protein nitrogen, 0.3 g ammonia, 89.8 g moisture, 8.0 g ether extractives, 135.2 g crude fibre, 266.9 g ash and 19.18 MJ gross energy/kg. Methionine and lysine contents were 3.95 and 4.29 g/100 g protein, respectively.

2. In one experiment, 0, 50, 100 or 200 g rabbit excreta/kg were substituted for maize in a broiler diet. Chickens receiving the diet containing 200 g rabbit excreta/kg gained significantly less weight to 8 weeks of age than those receiving other diets.

3. In a second experiment, 0, 100, 150 or 200 g rabbit excreta/kg were substituted primarily for maize in a broiler diet to provide equal energy and protein contents. Weight gains to 8 weeks of birds receiving these diets did not differ significantly. The uncorrected metabolisable energy content of the excreta was 9.15 MJ/kg.

4. There were no gross pathological changes in the birds fed on the experimental diets.     

Physiological actions of dinoterb,a phenol derivative: 2. Effects on isolated plant mitochondria and chloroplasts

Dinoterb, a contact herbicide, affects respiration and photosynthesis of mitochondria and chloroplasts. On mitochondria, at low concentrations, it acts as an uncoupler of oxidative phosphorylation; at higher concentrations, it inhibits the electron transport chains, probably before cytochrome c. On chloroplasts, dinoterb has a stimulatory effect on oxygen uptake in the reduced dichlorophenol-indophenol→methyl viologen couple; however, it is also an inhibitor of the Hill reaction and its site of inhibition is located before plastoquinone, near photosystem II.