B. K. Thompson

Effect of straw on the behaviour of growing pigs

Abstract The effects of straw on the behaviour of young growing pigs were studied in two experiments. In Experiment 1, groups of three pigs, aged about 7 weeks, were housed in raised decks with or without straw bedding. Time-lapse video recording showed no major differences between treatments in the amount or daily pattern of overall activity and feeding. Detailed observations showed that bedding reduced the incidence of rooting and chewing on pen-mates, but had little effect on other social activities such as mounting and aggressive biting. Experiment 2 compared groups of eight growing pigs aged about 10 weeks, housed in floor pens with or without a small amount of straw provided daily in a rack. Pigs with straw concentrated more of their daily activity into the period when straw was fresh, but the total amount of overall activity and time spent feeding were not affected. Rooting and chewing of pen-mates were the only social activities reduced by the provision of fresh straw. In these studies, where straw was not required to compensate for deficiencies such as low temperatures or hunger, the one major function of straw was to provide a stimulus and outlet for rooting and chewing, with a resulting reduction in such activities directed at pen-mates.

Crushing of piglets by sows: effects of litter features, pen features and sow behaviour

Abstract Crushing of piglets by sows in farrowing pens was studied in a 2×2 experiment to evaluate the effect of different pen design features. Pens had either concrete or plastic-coated expanded metal flooring, and half of the pens were fitted with a horizontal bar 23 cm above the floor, bisecting the pen. The bar was intended to prevent the sow from rolling suddenly onto her side, a movement known to crush piglets in open pens. Ninety-eight litters were analyzed during the first 3 days after birth when most crushing occurs. Of the 927 viable, live-born piglets, 95 (10.2%) died during the study, and 75 of these deaths were due to crushing as indicated by post mortem analysis. A high incidence of crushing was associated with larger litter size at birth, lower average piglet weight gain in early lactation, and older (high parity number) sows; however, these variables were interrelated, with older sows tending to have larger litters with lower early weight gains. Pens with a bar had significantly less crushing during the last 2 days of the study (Days 2–3), but this was fully offset by a non-significant tendency for more crushing in these pens on Days 0–1. Video recordings were analyzed for 16 sows with multiple crushings. Of eight types of sow body movement recorded, two caused most of the crushing: lying down from a standing position (54% of crushings observed), and rolling from lying on the udder to lying on the side (33% of crushings observed). Pen design features influenced how often the different movements were performed and how often these movements crushed piglets, but pen design did not affect the total number of movements or the total number of piglets crushed. Although the comparisons in the study did not result in significant differences in the incidence of crushing, the method shows promise as a way to identify design features that reduce the incidence of dangerous movements.

Response of growing swine to dietary exposure to pure fumonisin B1 during an eight-week period: Growth and clinical parameters

Consumption of corn or corn-based products contaminated with Fusarium moniliforme/fumonisins has been associated with a variety of animal and human diseases and is a major food/feed safety issue. This study focused on the clinical toxicity and performance parameters in growing swing exposed to low to moderate levels of pure fumonisin B1 (FB.) for 8 weeks. Male (castrated) and female pigs were fed diets containing 0,0.1,1.0, and 10 mg FB1/kg diet (ppm). Weight gains and feed consumption were measured weekly. Blood samples were collected throughout the study, and various clinical and hematological parameters were measured. Because fumonisins are potent inhibitors of sphingolipid biosynthesis, sphinganine and sphingosine concentrations were determined in the liver, lung, and kidney. Organ weights and carcass quality were measured at the end of the trial. In general, male pigs were more adversely affected by FB1 in the diet than females. The average daily gain for males decreased by 8% for pigs fed 1.0 ppm and by 11% at 10.0 ppm, when compared to the control (0 ppm). Males fed 0.1 ppm showed an erratic growth pattern during the first 5 weeks of the experiment. Feed consumption for the same animals was somewhat higher than that of the controls during each of the first 4 weeks but thereafter was 6-7% lower each week as compared to controls. Female pigs fed FB1-diets showed a general enhancement of feed consumption until week 4. Among clinical chemistry parameters, cholesterol increased in males for the 1.0 and 10.0 ppm diets as compared to controls after 2 weeks, while the levels in both sexes were elevated for the 1.0 ppm diet only by the end of the experiment. Serum liver enzyme concentrations were altered during week 2 only. Changes were observed in the weight of the pancreas and adrenals for male pigs fed FB1 diets as compared to controls. The free sphinganine to free sphingosine ratio (biomarker of exposure in FB1-consuming animals) increased in all three organs for the 10 ppm diet, regardless of sex. The study indicated that FB1 can cause different effects at each dose level, at concentrations as low as 0.1 ppm (showing erratic growth) followed by a reduced growth and biochemical abnormalities in blood (1.0 ppm) and sphingolipid alterations in tissues (10.0 ppm). Some of these effects occurred below the exposure level that caused alteration in sphingolipid metabolism.

Farrowing behaviour and stillbirth in two environments: an evaluation of the restraint-stillbirth hypothesis

A total of 59 farrowings were studied in either a conventional, narrow farrowing crate (0.43 m wide) or a much wider alternative design with sides spaced 1.2 m apart at the sows standing height but narrowing near the floor to limit the sows lying area. Using video recoding, we monitored each “birth interval” (i.e. the period between two successive births) and noted the intervals length, the sows posture and postural changes during the interval, and whether the interval ended with a live-born or stillborn piglet. The wide and conventional crates did not differ significantly in median interval between piglets (15.9 versus 16.0 min, respectively), incidence of stillbirth (5.8 versus 7.0%), in any measures of posture or postural change, or in piglet survival and weight gain to 3 days of age. Sows were most active during the first two birth intervals; as farrowing continued they made progressively fewer postural changes and spent more time lying. Sows differed greatly in the frequency of postural changes and the time they spent in different postures; however, these measures were largely unrelated to stillbirths, except that stillbirths were rare if the sow sat during much of the interval (P < 0.001). Birth intervals were longer, on average, before a stillbirth (median of 34 min) than before a live birth (13 min; P < 0.001). The greater incidence of stillbirths late in the farrowing was associated with a greater proportion of long birth intervals late in the farrowing, and greater likelihood of stillbirth even for shorter and medium intervals. Stillbirths were more common in longer farrowings (P ≈ 0.01), evidently because these tended to involve larger litter sizes and more long birth intervals of over 60 min. However, the proportion stillborn in a litter was not correlated with median birth interval. The results of this and related studies suggest that greater freedom of movement in the farrowing environment does not consistently produce shorter duration of farrowing or a lower incidence of stillbirth.

Sows show stronger responses to isolation calls of piglets associated with greater levels of piglet need

Abstract Natural sequences of calls produced by isolated domestic piglets were played to lactating sows ( N =24) separated from their litters. Two piglets from each of eight litters were recorded under conditions designed to influence their need for a rapid response from the sow. The ‘needy’ piglet was the smallest and slowest growing in the litter, had just missed a nursing and was isolated in a relatively cool enclosure. The ‘un-needy’ litter-mate was the largest and fastest growing, had just nursed and was isolated in a relatively warm enclosure. Calls from the needy piglets were of a higher rate, higher in frequency, and longer than those from the un-needy piglets. Sows responded to playback by orientating towards the loudspeaker and approaching it, by moving about the area near the speaker, by vocalizing and by reducing the duration of their own calls. Sows showed stronger responses to playback from needy piglets than from un-needy piglets by vocalizing more, moving more and spending more time near the playback speaker. Sows responded to the calls of their own piglets and to those from other litters, but showed a stronger response to calls of their own piglets.

Effect of the appetite stimulant cyproheptadine on deoxynivalenol - induced reductions in feed consumption and weight gain in the mouse

Deoxynivalenol (DON, vomitoxin), a Fusarium mycotoxin, is suspected of inducing its anorectic/feed refusal activity through a serotoninergic (5HT) mechanism, possible via 5HT2-receptors. In this study the efficiency of cyproheptadine (CYP), a serotonin antagonist and known appetite stimulant, to attenuate the adverse effect of DON was investigated in mice. CYP was administered in the feed for two days before animals began receiving the DON, which was also added to the feed. Both agents were administered concurrently thereafter for a 12-day period. Dosing levels included various combinations of the two compounds, ranging from 0-16 ppm DON and 0-20 ppm CYP.

Preference by sows for a partially enclosed farrowing crate

A preference testing apparatus was designed to give sows continuous access to three farrowing crates with different degrees of visual enclosure. A ‘fully enclosed’ crate had solid black panels on the sides and top of the crate, a ‘solid-sided’ crate had the side panels only and an ‘open crate’ had no solid panels over the crates tubular framework. The crates radiated from a central area sufficient for sows to enter or leave any crate freely. Video recording was used to determine sow position from 3 days before to 6 days after farrowing. The results indicated that younger sows (second or third parity) preferred the enclosure offered by the solid side panels during and for several days after farrowing (P < 0.05). Older sows, which had previously farrowed a number of times in an open crate, had no clear preference. A solid panel overhead did not improve, andmay have reduced the acceptance of a crate with solid sides. It is concluded that less experienced sows prefer a degree of enclosure on the sides of the farrowing crate, but that this preference largely disappears with repeated experience of open crates.

Early exposure to the opposite sex affects mating behaviour in White Leghorn chickens

Abstract To examine the effect of early exposure to the opposite sex on mating behaviour in White Leghorns we observed interactions between males and females that had been raised with (mixed-sex) or with-out (same-sex) the other sex. Groups of six females and one male were assigned to one of four treatments based on how they were raised: mixed-sex females with a mixed-sex male (MM), same-sex females with a same-sex male (SS), mixed-sex females with a same-sex male (MS) and same-sex females with a mixed-sex male (SM). Observations were conducted over an 8-week period beginning when the birds were 23 weeks old. Overall, MM and SS groups had significantly more successful copulations and a higher success rate than MS and SM groups, although the increased rate was mostly because of the influence of the MM group. Female behaviour was similar among treatment groups, although more mating attempts and more successful copulations occurred with top-ranking females in the MM and SS groups. Finally, MM and SS groups initially produced more eggs than the MS and SM groups, however, this difference disappeared over time. The results of this study show that early experience with the opposite sex enhances mating success in adulthood. However, it also indicates that matching males and females for experience is of importance.

The role of tryptophan in DON-induced feed rejection

Deoxynivalenol (DON, vomitoxin) commonly produced by Fusarium fungi can alter feeding behaviour of pigs and other farm animals. The effects of dietary tryptophan (TRP, precursor of brain amine serotonin) in combination with DON were examined in mice to determine if TRP can modulate DON toxicity. Results indicated that brain TRP can be influenced by dietary TRP, but no evidence of TRP potentiating DON toxicity was observed. Higher TRP levels likely induced amino acid imbalance leading to weight gain suppression.