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.     

Selection for food conversion in broilers: Direct and correlated responses to selection for body‐weight gain,food consumption and food conversion ratio

1. Direct and correlated responses were determined after five generations in four lines of chickens selected either for increased body‐weight gain (line W), for increased food consumption (line F), for decreased food conversion ratio (line E), or at random (line C).

2. Realised heritability estimates calculated after five generations of selection were : 0–37 + 0.04 for weight gain (WG); 0.44 + 0.05 for food consumption (FC); 0.21 + 0.04 for food conversion ratio (FCR).

3. Realised genetic correlation estimates were: WG and FC, +0.71 ±006; WG and FCR, ‐0.40±0.09; FC and FCR, +0.27 + 0.09.

4. Zero‐generation heritability and genetic correlation estimates were greater than the realised estimates, and sex linkage appeared to be important in the expression of all three traits.

5. The genetic correlation between FC and FCR was asymmetrical with considerable positive response in FCR in line F (r_g = +0.79) but negligible response in FC in line E (r_g = —0.01).

6. There was an apparent plateau in response in FCR in line E from the third to the fifth selected generations.     

Changes in plasma gonadotrophins, 17β-oestradiol,progesterone, prolactin,thyroxine and triiodothyronine concentrations in female Japanese quail (Coturnix coturnix japonica) of a heavy body weight line during photo-induced ovarian growth and regression

1. Simultaneous changes of the width of the cloacal opening and plasma luteinising hormone (LH), follicle stimulating hormone (FSH), 17β-oestradiol, progesterone, prolactin, thyroxine (T₄) and triiodothyronine (T₃) during photo-induced ovarian growth and regression were measured in commercially bred Japanese quail from a heavy body weight line.

2. Somatically mature female Japanese quail were transferred from short days (light:dark 8L:16D) at 10°C to long days (16L:8D) at 20°C, and sexually mature female Japanese quail were transferred from long to short days. All variables were measured at transfer and every five days thereafter (except for a measurement at 12 instead of 10?d) for 35?d.

3. Transfer from short to long days caused significant increases in LH, FSH, 17β-oestradiol, ovary weights and oviduct weights after five days, and in the cloacal opening after 12?d. T₃ decreased after five days, whereas no significant changes were observed in T₄ concentrations. Progesterone and prolactin both decreased after 25 long days.

4. The transfer of quail from long to short days caused significant decreases in LH, FSH, 17β-oestradiol, progesterone, prolactin, ovary and oviduct weights after 12?d and an increase in T₃. There was no significant change in T₄ concentrations. The cloacal opening decreased after 25 short days.

5. These results are the first to show simultaneous changes in gonadotrophins, sex steroids, thyroid hormones and prolactin during photo-induced gonadal growth and regression in female Japanese quail.     

Is there a relationship between clinical presentation,diagnostic and radiographic findings and outcome in horses with osteoarthritis of the small tarsal joints?

Reasons for performing study: Despite the possibility that sound horses may have radiographic signs consistent with osteoarthritis of the small tarsal joints (OA‐STJ), a diagnosis of ‘bone spavin’ as a cause of lameness is often made based only on radiographic examination. Objectives: To determine whether severity of radiographic change and response to treatment are correlated with the duration and degree of lameness and the response to intra‐articular anaesthesia in horses with OA‐STJ. Methods: A retrospective study of all horses that showed a positive response to intra‐articular anaesthesia of the STJ was performed. Details of history, clinical presentation and diagnostic findings were recorded. Radiographs of affected tarsi were evaluated and scored independently by 2 observers. Follow‐up was via a telephone questionnaire with the owner. Statistical analysis was used to assess the association between the duration and degree of lameness, the response to intra‐articular anaesthesia and radiographic findings. Response to treatment was compared with the findings from the diagnostic work‐up. Results: Ninety‐one horses were included (61 unilateral and 30 bilateral lameness). Fifty‐nine percent of horses had been lame for over 2 months. There was no association between the duration and degree of lameness, or between duration or degree of lameness, intra‐articular anaesthesia and radiographic findings. Response to treatment showed a significant positive association with less severe radiographic changes within the tarsometatarsal (TMT) joint. Follow‐up was available for 48% of cases, with 52% horses returning to the same level of exercise. Conclusions: There is no association between the duration and degree of lameness, the response to intra‐articular anaesthesia and radiographic findings in horses with OA‐STJ. However, horses that improved following treatment tended to have less marked TMT joint pathology. Potential relevance: Response to intra‐articular anaesthesia should remain the gold standard for diagnosis of OA‐STJ. Predicting which cases are likely to improve following treatment remains difficult.     

The effect of a single oral dose of non‐protein nitrogen from various sources on amino acid concentrations in the plasma and liver of the chick

1. Broiler chicks were fed normally for 21 d, then starved overnight and given a single oral dose of an aqueous solution of diammonium hydrogen citrate (DAHC), triammonium citrate (TAC), ammonium lactate (AL) or urea equivalent to 24.76 mg N. Controls were given water. The concentrations of free amino acids in the plasma were measured 2, 4 or 6 h after dosing. The only non‐essential amino acid significantly affected was glutamine, which increased in chicks given DAHG or TAC

2. In another experiment, non‐protein nitrogen (NPN) from the same sources was given at dosages of 124 mg N per chick. The concentrations of free amino acids in the plasma and liver were determined 2, 4 or 6 h after dosing. NPN from all sources increased the amount of glutamic acid and glutamine in both tissues (P< 0.001), although the response to urea was delayed. The concentrations of plasma aspartic acid (P<0.05), plasma alanine (P< 0.001) and liver aspartic acid (P< 0.001) also increased.

3. The results are discussed in relation to earlier studies with liver homogenates in vitro.     

A case study of conflict management in bonobos: how does a bonobo (Pan paniscus) mother manage conflicts between her sons and her female coalition partner?

Female coalitions are an important part of the social organization of bonobos. The strength of the mother-son relationship is another essential part of this social structure. A bonobo mother is therefore facing a dilemma when a conflict arises between her sons and her female coalition partners. Will she take her coalition partner's side and favour the social organization of the group or support her son in order to defend her offspring? In order to address this issue, we performed an observational study of the captive group at Planckendael (Belgium) and used social grooming and proximity to assess the relationship between individuals. As a case study, we focused on the relationships between Hortense, one of the group's mothers, her 3 sons Redi, Vifijo and Zamba, and her coalition partner Hermien. Surprisingly, we observed that Hortense preferentially supported her female coalition partner. For Hortense's social status in the group, it may be more important to maintain the strong relationship with her higher-ranking female coalition partner than to support her sons.