Effect of climate on the response to three oestrous synchronisation techniques in lactating dairy cows

The reproductive efficiency of Friesian dairy cows was investigated in a three (oestrous synchronisation technique) x two (seasons of the year) factorial design. The 90 primiparous and multiparous cows (winter, n=42; summer, n=48) were allocated at random to three synchronisation treatments (n=30 cows per treatment). In treatment 1 (GPG), the cows were administered 15 mg PGF(2alpha) i.m. at 30 +/- 3 days postpartum, 100 microg GnRH i.m. at 51 +/- 3 days and 15 mg PGF(2alpha) 7 days later. A second 100 microg dose of GnRH was given after, further 2 days and fixed time AI occurred 16-20 h later. In treatment 2 (PG-PG), 15 mg PGF(2alpha) was administered i.m. to each cow on three occasions at successive 14 days interval starting at 30 +/- 3 days postpartum and the cows were inseminated at observed oestrus following the third dose of PGF(2alpha). Cows in treatment 3 (PG) had a single administration of 15 mg PGF(2alpha) i.m. at 57+/-3days postpartum and were inseminated as in treatment 2. Mean daily ambient temperature was 10.9 degrees C in winter (November-March) and 20.2 degrees C in summer (June-October). The cows were confined in an open-fronted shed and had ad libitum access to a complete diet with a 37:63 forage to concentrate ratio. Body condition score was assessed at 57 +/- 3 days postpartum. Cow rectal temperature at insemination, milk yield, reproductive data and climatic variables were recorded. Blood samples were collected for progesterone assay on days 4, 11, 18, 25, 32, 39 and 46 post-AI from 54 of the cows (19 GPG; 17 PG-PG; 18 PG). Pregnancy rate to first AI was 36.7% (11/30) for GPG and 16.7% (5/30) for both PG-PG and PG treatments. The difference was not significant. The cumulative pregnancy rate after third AI were GPG 83.3% (25/30), PG-PG 60.0% (18/30) and PG 60.0% (18/30; P<0.057). The cumulative pregnancy rate for cows inseminated in the winter (81.0%; 34/42) was higher (P<0.01) than for those inseminated in the summer (56.3%; 27/48). The interval from calving to first service was shorter (P<0.05) in treatment PG-PG (65.4+/-1.3 days) than in PG (69.2+/-1.3 days). Mean plasma progesterone concentrations post-AI of pregnant cows were higher (P<0.001) for GPG cows than those for PG-PG and PG cows. Plasma progesterone levels of pregnant cows tended to be higher (P=0.087) in winter than in summer. In conclusion, although the cumulative pregnancy rate was higher for GPG cows, it may be appropriate to correct the nutrition and management of the herd before resorting to synchronisation techniques to improve animal reproductive performances.

Influence of flavor on goat feeding preferences

Goat feeding preferences for straw pellets flavored with ryegrass (Lolium perenne, cv. Belida) or white clover (Trifolium repens, cv. Huia) aromatic extracts, obtained by means of a cold aromatic extraction method, were assessed with cafeteria trials. Prior to the trials, odor differences between the two plant species, the two aromatic extracts, and the straw pellets sprayed with the two aromatic extracts were verified using sensory analysis performed by 30 human panelists. Since odor differences observed among fresh samples were still detectable in aromatic extracts and moistened pellets, the extraction method was considered effective in reproducing plant odors. Straw pellets sprayed with either distilled water (W) or ryegrass (R) or clover (C) aromatic extracts were used to assess flavor preferences of 12 female Rossa Mediterranea goats. Sprayed pellet preference was evaluated in two sessions conducted in two consecutive weeks. Each session consisted of three two-choice presentations performed on three consecutive days. In both sessions, food intake, proportion of food intake, time spent feeding, and proportion of time spent feeding were significantly affected by pellet type (0.05 > P > 0.001). In particular, straw pellets sprayed with ryegrass extract were highly selected compared to those sprayed with clover (0.01 > P > 0.001) or water (0.01 > P > 0.001). In addition, in the second session, the clover extract was preferred to distilled water (0.05 > P > 0.01). The results of this study gave two main indications: first, goat selectivity for rye-grass against clover was consistent even when straw pellets sprayed with odors of these plants were offered, and secondly, the addition of aromatic extracts to straw pellets increased the preference for pellets.

Effect of pen size on behavioral, endocrine, and immune responses of water buffalo (Bubalus bubalis) calves

Female water buffalo (Bubalus bubalis) calves (n = 28) aged 7 to 10 d were divided into four groups of seven animals each to examine the effects of space allowance (Group A: 2.6 indoor m2 + 2.0 outdoor m2/calf; Group B: 2.6 indoor m2/calf; Group C: 1.5 indoor m2/calf; Group D: 1.0 indoor m2/calf) on behavioral, endocrine, and immune variables for a period of 60 d. Animals were offered 7 L/d of a commercial acidified milk substitute. The calves averaged 45.9 kg initially and 92.4 kg finally. The behavior observations were conducted 7 d after grouping and fortnightly thereafter. At wk 4 and 8, the phytohemagglutinin (PHA) skin test was performed to induce aspecific delayed hypersensitivity. At wk. 1 and 3, calves were injected i.m. with keyhole limpet hemocyanin. Antibody titers were determined at weekly intervals for 7 wk. Calves in pens with greater space allowance (Groups A and B) were less active than Groups C and D (P<.001). The latter groups were also observed feeding more often at wk 7 (P<.01). Calves provided with an outdoor paddock spent less time standing than Groups C and D (P<.01), and lay with a greater number of outstretched legs (P<.001). Groups C and D showed a lower reaction to PHA in both skin tests than did Groups A and B (P<.001 and P<.05, respectively). Group A showed an antibody response consistently higher than groups B, C, and D (P<.01, P<.05, and P<.05, respectively). At the end of the experimental period, the calves were subjected to an isolation test lasting 10 min. Group D showed a longer duration of movement with respect to Groups A and B (P<.01); animals from Group C walked more than did Group A (P<.05). Cortisol concentration evaluated 0, 10, 45, 90, 150, and 225 min after separation from the group was higher in Groups C and D than in Groups A and B (P<.01). For all animals, the highest cortisol level was observed immediately after the isolation test (P<.001). Space restriction resulted in evidence of stress in the animals as shown by alterations in a number of physiological responses. However, the use of small groups of only seven animals per pen may have affected their reactions to space restriction. It is possible that using larger groups could change these conclusions.

Conditioned inhibition of antibody response and CD4 positive cells

Animals were assigned to three experimental groups, conditioned (cyclophosphamide-glucose treatment; C group), non-conditioned (cyclophosphamide-commercial pellet treatment; NC group) and placebo (saline solution-glucose treatment; P group). The three groups were injected intraperitoneally (i.p.) with sheep red blood cells. An hemagglutination assay according to standard procedures was performed along with the flow cytofluorometric analysis of leukocyte surface antigens CD4, CD8 and CD45. C group consumed less food on Days 3 and 6 than on Day 0, NC animals showed no changes in food consumption throughout the experimental period, whereas an increasing trend was observed for P animals. The proportion of T lymphocytes expressing CD8 and CD45 did not differ significantly among C, NC and P groups. Group C showed the lowest proportion of T lymphocytes bearing CD4, whereas Group P displayed the highest. The antibody response was lower in the Group C than in the groups NC and P. We conclude that, although the mechanisms by which humoral conditioned immunosuppression occurs in mice is still unknown, a reduced T helper-mediated activation of B-cells may play an important role in producing conditioned humoral response.

Use of monoclonal antibodies for radioimmunoassay of water buffalo milk progesterone

In order to standardize a radioimmunoassay of milk progesterone as a routine method for confirmation of oestrus and diagnosis of pregnancy in water buffalo, monoclonal antibodies against progesterone were produced. Hybridomas were prepared by fusing spleen cells from a Balb/c mouse immunized with progesterone 11 alpha-hemisuccinate-bovine serum albumin conjugate with the mouse myeloma cell line NS-1. Thirty wells out of 94 secreted anti-progesterone antibodies. Of the ten independent hybridomas derived, one (AF65) was suitable for the quantification of milk progesterone by radioimmunoassay. The tracer used in the assay was progesterone-11 alpha-hemisuccinate [( 2-125I]iodohistamine). The sensitivity of the assay was 50 pg/tube. The mean progesterone concentration at oestrus was 0.8 +/- 0.2 ng/ml increasing to 8.5 +/- 0.8 ng/ml 24 d later in pregnant animals.

[A-mode echography in surgery: a study of solitary thyroid nodules (author's transl)]

As part of their exploration of the possibilities afforded by A-mode ultrasonic investigation in several disorders of surgical interest, the authors report the results obtained in the study of solitary thyroid nodules. More precisely, after a brief explanation of ultrasonics, current apparatus for echography, and methods for echographic examination, they describe the semiological features exploited in A-mode echography: namely nodules with liquid content, mixed content, solid homogeneous content, and solid heterogeneous content. They conclude with considerations on the principles and indications of this diagnostic procedure in the light of their personal experience.