C. Mazzoni

Long-term liquid storage and reproductive evaluation of an innovative boar semen extender (Formula12®) containing a non-reducing disaccharide and an enzymatic agent

There are no reports of saccharolytic enzymes being used in the preparation of formulations for animal semen extenders. In the present study, the use of an innovative semen extender (Formula12®) in the long-term liquid storage of boar semen at 17°C was evaluated. The formulation included use of a disaccharide (sucrose) as the energy source precursor coupled to an enzymatic agent (invertase). The innovative extender was evaluated and compared in vitro to a commercial extender (Vitasem LD®) for the following variables: Total Motility (TM), Forward Progressive Motility (FPM), sperm morphology, membrane integrity, acrosome integrity, and chromatin instability. Boar sperm diluted in Formula12® and stored for 12 days at 17°C maintained a commercially acceptable FPM (>70%). Using the results from the in vitro study, an AI field trial was performed. A total of 170 females were inseminated (135 with Formula12® and 35 with Vitasem LD®). The pregnancy rates were 97.8% compared with 91.4%, and the farrowing rates were 96.3% compared with 88.6% when Formula12® and Vitasem LD® were used, respectively. The mean number of piglets born/sow were 14.92±0.46 compared with 13.83±0.70, and the number of piglets born alive/sow were 14.07±0.46 compared with 12.12±0.70 (P<0.05). The results obtained in this study demonstrated that use of the innovative concept to provide a precursor of glucose and fructose as energy sources for an enzymatic agent in an extender allowed for meeting the metabolic requirements of boar sperm during storage at 17°C. It is suggested that there was a beneficial effect on fertilizing capacity of boar sperm in the female reproductive tract with use of these technologies.

Double cloprostenol administration during mid luteal phase of oestrous cycle does not modify the interoestrous interval in gilts

The present study was undertaken to test the effect of two vulva injections of D-cloprostenol on day 7, 9 and 10 of oestrous cycle on the duration of the interestrous interval in gilts. Following a pre-treatment oestrous cycle, 87 gilts were assigned to receive vulva injections of 75 μg D-cloprostenol at 08:00 and 14:00 h on day 7 (D7; n=30), day 9 (D9; n=29) or day 10 (D10; n=28) of their second observed oestrous cycle. Across the treatments, the duration of the oestrous cycle with D-cloprostenol treatment (19.1±0.1 d) was not different from that of the previous oestrous cycle (20.1±0.4 days). Plasma progesterone concentrations were evaluated 6 h before and 24 and 72 h after D-cloprostenol treatment in the D9 group. Compared to pretreatment levels (9.6±0.4 ng/mL), plasma progesterone concentrations were reduced (P<0.05) at 24 h (6.3±1.0 ng/mL) and 72 h after treatment but complete luteolysis did not occur. These data indicate that in gilts double vulva administration of D-cloprostenol is not able to induce a complete luteolisys and hence the duration of the oestrous cycle is not modified.

Effect of prior insemination of dead sperm and gestation housing management on gilt fertility

Danbred gilts at about 120 kg were group housed for estrous detection. At detection of estrus, gilts either remained in pens (P) or were re-housed into individual gestation stalls (S) and were inseminated (DS), or not (SC), with a dose of frozen/thawed dead semen. Groups were P-DS (n = 81), P-SC (n = 70), S-DS (n = 98) and S-SC (n = 90). All gilts were inseminated with semen containing viable sperm at the second detected estrus and 24 h later. Pregnant gilts that were stall housed were moved to pens 35 d after insemination. There were no effects of insemination or housing management on farrowing rates or litter sizes.

Effects of three different designed farrowing crates on neonatal piglets crushing: preliminary study

Abstract In swine production, the economic gain in the farrowing room corresponds to the number of weaned piglets/sow per year. Pre-weaning mortality is at least 11–13% of total losses within one herd, considering a previous 7–8% of the stillbirths. Piglet crushing by the sow contributes significantly to the overall piglet mortality. It is caused by multiple factors related to the sow, the piglet and due to modern swine husbandry along the last 50 years. This study aimed to compare three different designs of farrowing crates during the first three days of life in relation to piglet-crushing mortality in intensive herd. One hundred fifty-eight sows with spontaneous deliveries were housed in the following farrowing crates groups: group A (n = 51) farrowing within conventional crates, group B (n = 47) farrowing within the slide cage and group C (n = 60) in the up and down designed, for a total of 2487 live born piglets. In the first three days of life, group C reported the lower crushing mortality rate (0.54%), while groups B and A reported 2.37% and 5.46%, respectively. The comparison between the group C value compared with group A values (p<.001; Chi-square = 36.90) and B (p = .003; Chi-square = 8.81) were statistically significant. In conclusion, the approach to create more space for both mother and litter within an acceptable size of farrowing crates (slide cage and up & down designed) allowed a significant reduction in mortality crushing rate of the piglets during the first three days of life.

Effect of duration of altrenogest treatment on farrowing rate and litter size of gilts

The objective of the present study was to compare two common durations of altrenogest (ALT) feeding during different periods of the year on the fertility of gilts after ALT withdrawal. During a 12-month period gilt replacements that were assumed to be cyclic were subjected to oestrus synchronisation with 15 mg/day ALT administered for 18 days (ALT-18; n = 268) or 14 days (ALT-14; n = 153) whereas 275 non-treated gilts served as controls. Fewer ALT-14 than ALT-18 gilts expressed oestrus by 7 days after last ALT treatment (79.1% vs 88.8%; P < 0.05). Farrowing rate was lower (P < 0.05) for ALT-14 than for the other groups (81%, 91% and 92% for ALT-14, ALT-18, and Control, respectively) but farrowing rates were not affected by time of year. Control litter sizes were not different from ALT-14 except during September to November when Control litter sizes were larger than either ALT treatments (13.6 ± 0.33, 12.3 ± 0.65 and 12.7 ± 0.39 for Control, ALT-14 and ALT-18, respectively; P < 0.05). The ALT-18 gilts had larger litter sizes during January to August. The present data suggest that the appropriate duration of ALT feeding to synchronise oestrus in gilts is 18 days.