Reference intervals and age-related changes for platelet count, mean platelet volume and plateletcrit in healthy pre-weaning piglets in Italy.

Platelet count (PLT) mean platelet volume (MPV) and plateletcrit (PCT) were determined for 117 Landrace x Large White piglets aged 3-21 days; counts were performed with an automated blood cell counter (ABX Pentra 120). Reference values were estimated following the guidelines of the International Federation of Clinical Chemistry (IFCC) and the International Committee for Standardization in Haematology (ICSH). The calculated central 95% reference limits for PLT was 49.9-516.2 x 10(9)/1, for MPV 6.71-9.91 fl and for PCT 0.009-0.395%. When observations are divided into three age groups (about 1 week each) there is an increase in mean PLT count and PCT in 2-week piglets, and a decrease in MPV from the first to the third week of life. These reference values provide guidelines for interpreting for experimental and clinical observations, as well as for monitoring of the health status of similar aged piglets determined using automated impedance-light focusing methodology.

Boar semen controlled delivery system: storage and in vitro spermatozoa release.

Swine spermatozoa were encapsulated in barium alginate and protamine-barium alginate membranes to lengthen their preservation time and to provide a means of controlling their release. Precocious acrosome reactions and secondary anomalies were measured as indices of semen quality. These characteristics were observed for two forms of encapsulated spermatozoa when stored at 18 and 38 degrees C for 24 h and for semen diluted in a classical extender at both temperatures. The results indicate that encapsulation enhances semen preservation, providing protection against membrane damage upon dilution. The effect is even more evident at the higher temperature (38 degrees C), where cell metabolism is higher. An in vitro release test of spermatozoa showed a massive cell delivery from barium alginate capsules within 6 h, and a slow release from protamine-barium alginate capsules. The properties of spermatozoa 24 h after release did not differ from the semen stored at the same temperature in capsules, indicating that the release process does not impair semen quality.

17beta-estradiol, progesterone and testosterone concentrations in cystic fluids and response to GnRH treatment after emptying of ovarian cysts in dairy cows.

The aim of this study was to determine possible links between steroidogenic activity of single ovarian cysts and response to intramuscular treatment with 20 microg of buserelin (GnRH-analogue) after cyst emptying, in pluriparous Friesian cows bearing a singleton cyst treated not earlier than 55 days post-partum. Progesterone, 17beta-estradiol and testosterone were determined in cystic fluids collected by needle aspiration of the cyst. Of the cows, 75.6% began ovarian cyclicity within 30 days after treatment with a conception rate of 64.7%. In this study it was found that as progesterone concentration in cystic fluids rose, the number of positive responses to the treatment fell.

Boar semen controlled delivery system: analysis of batch seasonal variability.

A new encapsulation technology of swine semen is proposed to improve the quality of stored spermatozoa and to obtain the controlled release of viable cells, reducing the number of instrumental inseminations. This technology has been employed to produce barium alginate gel capsules in different seasons; an analysis of batch reproducibility was performed, and total capsule diameter, gel thickness and weight of capsules were determined as indices of batch properties. A seasonal variability was found but each batch was substantially homogeneous. The variability could be related to the biological variability of the semen employed as raw material as well as to the technological process.

Barium alginate cell-delivery systems: correlation between technological parameters.

The most recent trends for the development of several in vitro cell cultures have been oriented towards the cell immobilisation in 3-dimensional scaffolds and cell encapsulation. In fact, an important requirement of cell survival is self-assembly in functional communities, in the presence of an artificial extracellular matrix. In our research, a previously described technique for spermatozoa encapsulation was applied to obtain capsules loaded with an opaque agent as a model, and to perform a formulative study. A process variable, barium ion concentration, was correlated to some capsule properties, such as weight, gel thickness, total and core diameter. Ion concentration can be modified to obtain capsules with predictable characteristics.

Fumonisin B1 carry-over into milk in the isolated perfused bovine udder.

The mycotoxin fumonisin B1 (FB1) causes a variety of health problems in animals, while epidemiological evidence suggests it is linked to human esophageal cancer. We investigated the carry-over of FB1 into bovine milk using the isolated perfused bovine udder. Two mg of FB1 was injected into the perfusion blood of 3 udders, and milk and perfused serum levels were determined for 150 min. FB1 passed through the mammary barrier into the milk, but in such low concentrations as to present a negligible risk for consumers.

Purification and primary structure of a new bovine spermadhesin.

Z13 is a new seminal plasma protein made up of two disulfide-linked 13-kDa subunits that was identified in our laboratory by 2D PAGE. In this report we present the purification of Z13 from bovine seminal plasma. In solution, the protein is a nonglycosylated dimer that presents one interchain disulfide bond and does not show heparin-binding properties. The complete primary structure and the localization of the S-S bridges are reported. The results suggest that Z13 is a new protein of the spermadhesin family whose members are thought to play a prominent role in different aspects of fertilization.

Controlled release of swine semen encapsulated in calcium alginate beads.

A quick and successful encapsulation method of swine spermatozoa is described: hydroxypropylmethylcellulose and calcium chloride were added to the sampled ejaculate swine sperm (sperm-rich fraction: creamy white) and then this suspension was dropped into an aqueous solution of sodium alginate. In order to obtain different capsule thicknesses, different calcium chloride concentrations were used. The influence of different formulations on in vitro spermatozoa release behavior and on the mechanical properties has been studied. In vitro sperm kinetics (motility and average velocity) have been determined. The results obtained from motility and average velocity tests of treated seminal material are promising, especially if the difficulty of preservation of swine spermatozoa compared to bovine sperm is considered. The different membranes obtained from the different calcium concentrations have had an influence on mechanical properties and on the release profile of spermatozoa from the capsules, and therefore, it is possible to modulate the release rate of the cells.

Haematology and plasma biochemistry of Stamboek pre-pubertal gilts in Italy: reference values.

Blood samples were taken between February and April from 105 healthy Stamboek pre-pubertal gilts, aged 1-3 months, which were housed at a modern pig farm in northern Italy. The blood was analysed for nine haematological and nine selected haematochemical variables by means of automated and semiautomated blood analysis apparatus. After detection and rejection of outliers, the data were submitted to reference limits evaluation, also taking into account the limits for the red blood cell volume histogram as the anisocytosis index. Some haematological reference values deal with previously published data; in the haematochemical parameters, several discrepancies between evaluated limits and existing reference limits were noted, mainly for aspartate aminotransferase, alanine aminotransferase and lactate dehydrogenase levels and total protein concentration. The results confirm the relevance of age in determining blood reference intervals and that 'normal' values should be determined by each laboratory, taking into account the age of subjects, the sample size and methods of analysis.

Two-dimensional polyacrylamide gel electrophoresis map of bovine ovarian fluid proteins.

Molecular mechanisms underlying the cystic degeneration of ovarian follicles in the dairy cow have not been clarified yet. A useful approach for complementing endocrinological and clinical studies could be represented by the systematic analysis of the protein patterns in follicular and cystic fluid. With this aim, a two-dimensional polyacrylamide gel electrophoresis map of proteins contained in fluid from bovine ovarian follicles at different stages of development and from bovine ovarian cyst has been obtained. About 200 spots were detected after silver staining. Polypeptides from nine spots or series of spots have been identified by N-terminal sequencing, and further analysis of the map has been performed by gel comparison. Alpha-1-antitrypsin, albumin, serotransferrin and apolipoprotein A-I and A-IV were located on the map. Comparison between protein patterns revealed the differential expression of some spots among follicles of smaller diameter, follicles of larger diameter, and cysts. This could represent the first step toward the identification of proteins differentially expressed and associated with ovarian cyst development.

Two-dimensional polyacrylamide gel electrophoresis map of bull seminal plasma proteins.

A two-dimensional polyacrylamide gel electrophoresis map of bull seminal plasma proteins has been established. About 250 spots were detected after silver staining and polypeptides from 24 spots have been N-terminally sequenced. Major proteins already described in bull seminal plasma, like PDC-109 and aSFP, have been located on the map; proteins not yet reported in male reproductive tracts have been evidenced; for some polypeptides showing a previously unknown N-terminal sequence, structural similarities with proteins described in other organisms have been found. A reference map of seminal plasma proteins could be useful in relating protein pattern changes to physiopathological events influencing the reproductive sphere.

Induction of estrus in cows by a new analogue of PGF2 alpha (alfaprostol).

A new analogue of PGF2 alpha, alfaprostol, was used to induce estrus in normally cycling and anestrous cows. Five groups of six animals were treated with single injections of different doses of the drug (4, 5, 6, 7 or 8 mg/animal) on day 10-11 of the estrous cycle. Six cows in anestrus, with palpable corpora lutea, were treated i.m. with 8 mg/animal. The luteolytic properties of alfaprostol were assessed by measuring milk progesterone by RIA for 96 h after treatment and by checking for the subsequent signs of estrus. The dose of 4 mg caused a slight fall in progesterone but did not induce heat; the 5 and 6 mg doses induced estrus in 3/6 animals and the 7 mg dose was effective in 4/6 animals. The 8 mg dose produced a sharp reduction in milk progesterone within 24 h, followed by estrus in both the normally cycling and the anestrous groups in 6/6 animals. No clinical signs of drug intolerance were seen. The present results show that alfaprostol might be of great use for both cycle synchronization in normally cycling cows and for treatment of anestrus caused by a persistent corpus luteum.

[Evaluation of PO2, PCO2, pH, and B.E. in milking cows in different milking phases]. / Valutazione del PO2, PCO2, pH E B.E. nelle bovine da latte durante le diverse rasi di lattazione.

During one year we studied the acid-base state in the milking cows trying to solve the relationship between the secretion disorders and feeding. THe results confirm that exist a link between the acid-base state and the disorders. These disorders are connected to problems of alimentation. In our experiments it had been possible to observe a change in pH of blood versus alkalosis.

The effects of PGF2 alpha on respiratory and cardiovascular variables in pig.

PGF2 alpha was injected into different parts of the circulatory system (intravenously by femoral and jugular veins, into the pulmonary artery, into the ascending or descending aorta and into the internal carotid artery at a level above the sinus and carotid body) of anaesthetized spontaneously breathing pigs. It caused changes in respiratory and cardiovascular variables. In vagosympathectomized animals the changes in pattern of breathing produced by PGF2 alpha were greatly reduced and total lung resistance was increased. This may indicates more than one site of action of PGF2 alpha, lung resistance being influenced by a direct action of PGF2 alpha and by an immediate reflex while the pattern of breathing being modulated by vagal efferents from the lungs.

Practical and experimental studies on the use of prostaglandins F2alpha in pigs.

The possible practical uses of F2alpha prostaglandins (two different experimental preparations) in pigs are discussed. It was shown that the intramuscular injection of 1-2 mg PGF2alpha (in the region behind the ear) could result in oestrus, ovulation and subsequent conception in a considerable number (78.3%) of virgin pigs with persistent clinical anoestrus (15-16 months old), the start of normal oestrous cycles in pigs 10-11 months old and also the early appearance of oestrous symptoms in pigs of prepuberal age (6-7 months). As the PGF2alpha treatment did not have any adverse effects on the composition and the normal growth of the piglets (except for a smaller litter size in the prepuberal gilts, probably due to age of the animals), while transitory side-effects only occurred exceptionally after treatment (slight excitement), the use of PGF2alpha is suggested for production of functional recovery in virgin gilts with apparent persistent clinical anoestrus, for the synchronization of oestrus in primiparous gilts on farms with no apparent reproductive disorders, and for the concentration of births also in pluriparous pigs past the 12th day of the normal oestrous cycle before injection, and for the induction of precocious oestrus and subsequent early conception in gilts of prepuberal age.